LVETc and PEPsu were automatically measured from electrocardiogram and finger photoplethismography. Atrioventricular (AV) and mode switch (CRT to DDD) were used as hemodynamic challenges. Performance of SI, beat-by-beat systolic blood pressure (SBP), and Doppler aortic velocity/time integral (AoVTI) were compared in 36 patients, and SI's detection of CRT to DDD mode switch in nine patients, responders to CRT. AVs were changed from 30 ms to 250 ms (20 ms steps) at constant paced heart rate, alternating with a reference AV (RefAV), to reduce hemodynamic drift. The coefficient of variation (standard deviation/mean) of SI, SBP, and AoVTI during all RefAVs were used as error marker. The percentage detection of hemodynamic changes during AV transitions was a marker of sensitivity.

Fifty-five patients (males 62%, age 69.6 ± 17) were studied. SI detected 441 of 544 transitions (81%) versus 361 (66%) of SBP (P = 0.005). Error during RefAVs was smaller for SI (3.4%) as compared to AoVTI (7.8%, P = 0.015) and to SBP (5.7%, P = 0.005). SIs correlated with AoVTI (R from 0.71 to 0.98, all P < 0.001). SI detected all CRT to DDD changes (P < 0.001).

The noninvasive SI obtained with a simple, observer-independent hemodynamic assessment procedure has higher accuracy than SBP and AoVTI and better sensitivity than SBP. It detects mechanical resynchronization in CRT and allows programming a suitable AV delay.

Lesion characteristics and EGM components on the proximal and distal bipoles of the ablation catheter in first-time AVN ablation procedures were analyzed. Outcomes of each lesion, including presence of CAB, acute recurrence of AVN conduction, new-onset right bundle branch block (RBBB), and junctional escape rhythm, were analyzed. Multivariate binary logistic regression analysis was performed to identify EGM characteristics that independently predicted the outcomes of interest. Lesions with these EGM characteristics were then identified and their outcomes compared with the whole cohort.

A total of 441 ablation lesions were analyzed. EGM characteristics that independently predicted outcomes were the presence of His and atrial EGMs on the distal bipole and the absence of ventricular EGM on the proximal bipole. Among the 25 lesions with all these characteristics, 18 (72%) resulted in CAB compared to the overall cohort rate of 38% (P = 0.001). There was no new-onset RBBB. The likelihood of acute recurrent AVN conduction and junctional escape rhythm were similar.

Combining proximal and distal bipole EGM characteristics of the ablation catheter can improve the accuracy of AVN localization during AVN ablation and avoid right bundle branch injury.

This single-center, prospective, matched control study included 45 patients who underwent atrial fibrillation ablation using a remote RCS compared to 45 patients who underwent conventional ablation. All patients had circumferential pulmonary vein isolation (PVI), roof, and MI ablation.

There were no significant differences in baseline clinical characteristics. There were no significant differences in MI block (RCS: 44/45 [98%] vs Control: 43/45 [96%], P = 1.0), roof block (RCS: 45/45 [100%] vs Control: 44/45 [98%], P = 1.0), and PVI (RCS: 45/45 [100%] vs Control: 45/45 [100%], P = 1.0). Ablation and procedural times were similar in both arms. Using RCS, mean total MI ablation and procedure times were 13 ± 6 minutes and 23 ± 15 minutes, respectively. Coronary sinus (CS) ablation was significantly less in the RCS arm (48% vs 72%, P = 0.03). It was possible to “drive” the ablation catheter into the distal CS using the RCS in 19/22 (86%) patients. There was a significant trend of reduction in mean MI ablation (P = 0.008) and procedural times (P = 0.004) over the course of the study period. There was a significant reduction in fluoroscopy time in the RNS arm (33 ± 17 minutes vs 49 ± 20 minutes, P = 0.0004).

It is feasible and safe to use a remote RCS for MI ablation, including “driving into the CS.” MI block was achieved in 98% with a significant reduction in the need for CS ablation (48%). There is a short learning curve.

From January 2010 to July 2012, six patients were identified who had idiopathic ventricular arrhythmias that apparently decreased (by greater than 90%) with preprocedural anxiety. The number of ectopic ventricular beats per hour (VPH) was calculated from Holter or telemetry monitoring to assess the ectopic burden. The mean VPH of 24 hours from Holter before admission (VPH-m) was used as baseline (100%) for normalization. β₁-Blockers, isoprenaline, and/or aminophylline were administrated successively on the ward and catheter lab to evaluate their effects on the ventricular arrhythmias.

Among 97 consecutive patients with idiopathic ventricular arrhythmias, six had reduction in normalized VPHs in the hour before the scheduled procedure time from (104.6 ± 4.6%) to (2.8 ± 1.6%) possibly due to preprocedural anxiety (P < 0.05), then increased to (97.9 ± 9.7%) during β₁-blocker administration (P < 0.05), then quickly reduced to (1.6 ± 1.0%) during subsequent isoprenaline infusion. Repeated β₁-blocker quickly counteracted the inhibitory effect of isoprenaline, and VPHs increased to (120.9 ± 2.4%) from (1.6 ± 1.0%; P < 0.05). Isoprenaline and β₁-blocker showed similar effects on the arrhythmias in catheter lab.

In some patients with structurally normal heart and ventricular arrhythmias there is a marked reduction of arrhythmias associated with preprocedural anxiety. These patients exhibit a reproducible sequence of β₁-blocker aggravation and catecholamine inhibition of ventricular arrhythmias, including both repetitive ventricular premature beats and monomorphic ventricular tachycardia.

DF leads from different manufacturers and the QuickFlex and QuickFlex μ CS leads were subjected to simulated differential pulling.

Restitution from differential pulling followed three patterns: complete, partial without escalation, and incomplete with escalation. Only the last pattern (only shown by the Riata 8F and ST 7F leads) was associated with an increased risk to CCE*. For CS leads, deformation concentrated on the more flexible segment when the lead body did not have a uniform construction.

The Durata, Riata ST Optim, QuickFlex μ, and Quartet leads should be relatively immune to CCE*. The Durata leads are extremely resistant to longitudinal deformation and probably cause mediastinal displacement rather than differential pulling in response to pectoral movements in vivo. Implantation techniques and lead designs can be used to minimize the risk of CCE*. A bench test for CCE* can be constructed.

Sixteen patients (age, 68 ± 10 years; 11 males, 69%) with heart failure and concomitant AF (duration 55 ± 86 months) underwent intraoperative epicardial electrophysiological mapping and a GP ablation using the maze procedure at our institution. Twenty-four-site, high-frequency stimulation (1,000/min; output, 18 V; pulse width, 0.75 ms) was performed by placing tweezers directly onto the potential GP sites on the left atrial epicardium.

Active GPs were found in 13 (81%) of the 16 patients, and 12 (92%) of 13 patients had active GPs between the right pulmonary veins (PVs) and the interatrial groove. For those patients with active locations, a 7-day event-loop recording demonstrated that 12 (92%) of 13 patients were maintained in sinus rhythm 3 months after the operation.

Dense epicardial mapping in the potential GP areas identified active GP locations in a high percentage of patients. GPs between the PVs and interatrial groove have a high potential as ablation targets for treatment of concomitant AF.

A total of 21 consecutive RHD patients with AT after a valve replacement were enrolled in this study. The mean interval between the occurrence of symptomatic AT and the surgical intervention was 38.2 ± 48.7 months. The initial procedure was performed 8.4 ± 8.9 months after first onset of AT. During the first procedure, an electroanatomic mapping was completed for 25 ATs, 18 of which were cavotricuspid isthmus-dependent atrial flutter, five that were right atrial free wall AT, and two that were left AT. Acute success was obtained in 95% (20/21) patients. Nine patients with recurrent AT had repeat radiofrequency catheter ablation, and newly developed left AT was identified in five patients after the first right AT ablation. After a mean follow-up of 42.7 ± 17.3 months, only 33% of the patients remained free of ATs, while 14% and 53% of the patients had AT recurrence and the development of atrial fibrillation (AF), respectively.

Right but not left macroreentry is the most common AT postmitral valve replacement in patients with RHD. The incidence of AF is very high after AT ablation in such patients during the long-term follow-up.

Inpatient data were obtained from the Kids’ Inpatient Database for the years 2000, 2003, 2006, and 2009. Outpatient data were obtained from the California, Maryland, and New Jersey State Ambulatory Surgery Databases for the years 2006 and 2009. Logistic regression was used to predict the odds of major complications from CA.

There was a 20% increase (4,134–4,967) in the number of pediatric CAs performed from 2006 to 2009 that was concomitant with a decrease in the percentage of those procedures being performed as inpatient procedures (2,254–1,846). In 2009, a complication rate of 4.81% was estimated. For inpatient CAs, higher risk patients (with congenital heart disease, congestive heart failure, or heart transplant), ablations for ventricular tachycardias, and low-CA-volume hospitals were associated with increased risk of complications. In 2009, the mean cost of a hospitalization involving CA, but no cardiac surgery, was $17,204 (standard error = $1,015).

CA has increasingly been used over the past decade for pediatric patients with a multitude of tachycardia mechanisms. There continues to be a small risk of major complications, especially for higher risk children and in hospitals with more limited experience with the procedure.

Two hundred and forty patients were randomized in this prospective, double blind placebo-controlled trial to either 1,200-mg oral-NAC two times a day (n = 120) or placebo (n = 120) starting 48 hours before and up to 72 hours after open heart surgery.

The mean age was about 60 years, and 75% were male. Patients in the NAC group were older, with higher percentage of acute coronary syndrome, hypercholesterolemia, and left internal mammary artery use. Coronary involvement and hypertension were more prevalent in the placebo group. All other baseline patient characteristics were similar between groups. Overall POAF developed in 13.8% of the patients. There was no difference in the incidence of POAF between the NAC vs placebo groups (11.7% vs 15.8%, respectively; P = 0.34). Postoperative hospital stay, morbidity, and mortality were similar in both groups.

Prophylactic high-dose oral-NAC begun 2 days before open heart surgery and continued for 5 days, and had no significant effect on the incidence of POAF, in-hospital stay, and postoperative morbidity or mortality.

There was a retrospective chart review of 98 patients who died in the ICD arm of multicenter automated defibrillator implantation trial II (MADIT II). The pattern of ICD management and the frequency of ICD shocks delivered before death were reviewed.

We identified three groups: Group 1 consisting of individuals who underwent ICD, deactivation, 15 (15%); Group 2 patients without ICD deactivation who were in hospice or with “do not resuscitate” (DNR) orders, 36 (37%); and Group 3 patients without ICD deactivation who were not in hospice care and did not have DNR orders, 47 (48%). Out of 15 deactivations, 11 (73%) occurred in the week before death. None of the patients in Group 1 received an ICD shock in the 24-hour period before death. However, one (3%) patient from Group 2 and nine (19%) patients from Group 3 had shocks during the 24 hours before death (P = 0.03). In the last week before death, three (20%), two (6%), and six (13%) patients received ICD shocks in the three groups, respectively (P = 0.28).

In patients with terminal conditions who are at risk for imminent death, active management of the patient's ICD, including timely discussions regarding ICD deactivation, may reduce the risk of ICD shocks during the end of life.

We investigated semipermanent transvenous pacing systems consisting of one (n = 57%) or two (n = 3%) bipolar active-fixation pacing leads and an attached epicutaneous pulse generator implanted from 2000 to 2009. The study population comprised 60 patients aged 72.9 ± 10.5 years (44 [73.3%] male). Forty-two (70%) were enrolled for complete system explantation for cardiac-implanted electronic devices associated infection. Eighteen (30%) required temporary pacing in the context of a variety of mostly severe cardiac and noncardiac conditions. The semipermanent pacing systems were removed after implantation of permanent systems or recovery of a noncompromising heart rhythm, respectively.

Transvenous semipermanent lead implantation was successful in 59 (98.3%) patients. Major and minor intraoperative complications occurred in one case (1.7%) each. The semipermanent systems were left in situ for a mean period of 14.6 ± 8.1 days). They served as a bridge to permanent system implantation in 68.3% (n = 41) and as a bridge to recovery of a noncompromising heart rhythm in 11.7% (n = 7). Four patients (8.3%) died with the semipermanent pacing system in situ, and seven (11.7%) were transferred to external hospitals with semipermanent pacing systems.

Transvenous semipermanent pacing with bipolar active-fixation leads and epicutaneous pulse generators provide an important option for prolonged temporary pacing as a bridge to permanent system implantation or recovery.

Of 909 patients with CRT device implantation between September 1998 and July 2008, 814 patients had pre- and post-CRT echocardiogram. A total of 95 patients with LVEF ≥ 50% following CRT were classified as super-responders. For 92 super-responders, who had U.S. Social Security numbers, an age- and sex-matched example was selected from the Social Security Life Tables. An expected survival plot of the matched population was then compared to the actual survival of super-responders.

Super-responders had comparable survival to the age-sex matched general population (P = 0.53), and Kaplan-Meier survival analysis in 92 patients showed that super-responders with CRT pacemakers had similar survival to those with CRT implantable cardioverter defibrillators (P = 0.77). Super-responders were more likely to be females (54% vs 25%, P < 0.001) and less likely to have significant coronary artery disease (62% vs 42%, P < 0.001).

Normalization of LVEF by CRT improves survival to levels comparable to the general population. This observation favors the concept that some CRT candidates have a cardiomyopathy likely generated by the conduction abnormality that is reversible through biventricular pacing.

The classification of adhesions with respect to the intraoperative adhesion coverage was as followed: class 0 = adhesion free; class 1 ≤ 30% of adhesion coverage; class 2 = 30–60% of adhesion coverage; and class 3 ≥ 60% coverage. Patient data between December 2010 and March 2012 were collected. A total of 100 leads were extracted from 58 patients (1.7 ± 0.8 leads/patient); the mean lead implant duration was 78.5 ± 66.7 months, and the percentage of PM/ICD leads was 68% (n = 68)/32% (n = 32).

Distribution of the leads among classes: 0 = 10; 1 = 17; 2 = 25; and 3 = 48. Average implant times (months) according to the adhesion classes: 0 = 1.2 ± 0.4; 1 = 19.8 ± 19.2; 2 = 79.3 ± 46.6; and 3 = 115.1 ± 106.0 (correlation-coefficient 0.71; P ≤ 0.05). Average numbers of extraction tools used according to the adhesions: 0 = none; 1 = 0.4 ± 0.7; 2 = 1.6 ± 1.0; and 3 = 2.3 ± 1.2 (correlation coefficient = 0.67; P ≤ 0.05). Complete removal was achieved in 100% of the patients in classes 0 and 1; 96% in class 2 (n = 24); and 75% in class 3 (n = 36) (P ≤ 0.05). Mortality = 0.

Extensive adhesions in the generator pocket predict the need for a higher number of extraction tools. High-grade pocket adhesions predict lower success rates with regard to complete lead extraction. Both findings suggest that the degree of pocket adhesions predicts the degree of intravascular adhesions.

Twenty-one consecutive patients (mean age 13.5 ± 2.4 years) symptomatic for AVNRT were prospectively enrolled to right atrium EA mapping and electrophysiological study prior to cryoablation. Cryoablation was guided by slow-pathway potential and performed using a 4-mm-tip catheter.

Sustained slow-fast AVNRT was inducible in all the patients with a dual AV nodal physiology in 95%. Acute success was achieved in 100% of the patients with a median of two cryo-applications. Fluoroless ablation was feasible in 19 patients, while in two subjects 50 seconds and 45 seconds of x-ray were needed due to difficult progression of the catheters along the venous system. After a mean follow-up of 25 months, AVNRT recurred in five patients. All the recurrences were successfully treated with a second procedure. In three patients, a fluoroless cryoablation with a 6-mm-tip catheter was successfully performed, while in the remaining two patients, a single pulse of 60 seconds of radiofrequency energy was applied under fluoroscopic monitoring. No complications occurred.

Combination of EA mapping systems and cryoablation may allow to perform fluoroless slow-pathway ablation for AVNRT in children and adolescents in the majority of patients. Fluoroless slow-pathway cryoablation showed a high efficacy and safety comparable to conventional fluoroscopy guided procedures.

To investigate the association between polymorphisms of IL-1 cluster genes and lone AF.

DNA samples were collected from 70 proven lone AF patients and 70 healthy subjects. Genomic DNA was typed for the variable number of the tandem repeat (VNTR) IL-1 receptor antagonist (RN) gene polymorphism, IL-1B –511 C > T(rs16944) promoter polymorphism, and +3953 C > T(rs1143634) polymorphism in exon 5 by polymerase chain reaction.

In lone AF group the frequency of IL-1RN2/2 and IL-1RN1/2 genotypes were higher than in the control group (7.2% vs 4.3% and 48.5% vs 22.8%, respectively; χ² = 14.1; P = 0.028). The frequency of allele 2 was significantly higher in the lone AF group (32.1% vs 15.7%; χ² = 10.7; P = 0.005). Allele and genotype distribution of IL-1B –511 C > T and +3953 C > T polymorphisms were not statistically different between the groups. C-reactive protein (CRP) levels were higher in lone AF patients compared to the control group (median = 1.25, interquartile range [IQR] = 0.85 vs median = 1.08, IQR 0.46 mg/L, respectively; P = 0.02). In multivariate regression analysis, presence of allele 2 of IL-1 VNTR polymorphism and elevated plasma high-sensitive-CRP levels were the independent predictors of lone AF.

Presence of allele 2 of VNTR polymorphism of IL-1RN gene may cause increased risk for lone AF probably due to the inadequate limitation of inflammatory reactions.

Different techniques have been adopted for the cannulation of the axillary vein. We report our experience using the outer edge of the first rib below the inferior border of the clavicle as fluoroscopic landmark.

A subcutaneous pocket is created 1-cm medially and parallel to the delto-pectoral groove and 2 cm below the clavicle. An 18-gauge needle from the upper border of the pocket is directed perpendicularly to the outer edge of the first rib just below the inferior border of the clavicle. If the vein is not entered, the needle is withdrawn and the puncture is repeated with slight variations of needle direction for a maximum of four to five times, then contrast-guided vein puncture is performed. Upon successful vein puncture, a guidewire is inserted and positioned in the superior vena cava. The remainder of the implantation is carried out in a routine manner.

The axillary vein was successfully cannulated without venography in 172 of 182 consecutive patients (94.5%); the vein could not be found in 10 patients (5.5%): in these patients the vein was successfully cannulated after venography performance. No pneumothorax, hemothorax, or brachial plexus injury occurred.

Our approach of axillary venipunture using fluoroscopic landmark, without contrast venography, is simple, safe, and effective.

To evaluate the novel multipole method of the HRV analysis in prediction of imminent VTAs in ICD patients.

We screened patients from the Biotronik HAWAI Registry (Heart Rate Analysis with Automated ICDs). A total of 28 patients from the HAWAI registries (phase I and II), having medical records, who had experienced documented, verified VTA during the 2-year follow-up, were included in our analysis. HRV during preepisode recordings of 4,500 R-R intervals were analyzed using the Dyx parameter and compared to HRV of similar length recordings from the same patients that were not followed by arrhythmia.

Our study population consisted mainly of men 25 of 28 (89%), average age of 64.8 ± 9.4 years, 92% with coronary artery disease. HRV during 64 preevent recordings (2.3 events per patient on average) was analyzed and compared with 60 control recordings. The multipole method of HRV analysis showed 50% sensitivity and 91.6% specificity for prediction of ventricular tachycardia/ventricular fibrillation in the study population, with 84.5% positive predictive value. No statistically significant correlation was found between various clinical parameters and the sensitivity of imminent VTA predetection in our patients.

The multipole method of HRV analysis emerges as a highly specific, possible predictor of imminent VTA, providing an early warning allowing to prepare for an arrhythmic episode.

Twenty-one patients with an implanted ICD or cardiac resynchronization therapy with defibrillator (CRT-D) were enrolled into the study. EECP had applied as two sessions of 5 minutes. Data from device interrogations before and after the first EECP session and during second EECP session were recorded and analyzed for signs of possible device interaction.

There was no sign of inappropriate sensing or noise during EECP session. There was no difference regarding electrode impedance, pacing, and sensing values before and after EECP. There was a statistically significant difference regarding heart rates during EECP therapy between rate response off and on modes (68.69 ± 5.92 beats/min and 90.32 ± 11.05 beats/min, respectively P = 0,001). In four patients with CRT-D and unipolar left ventricular pacing, counterpulsation could not be done because of QRS sensing problems.

EECP seems to be a safe treatment modality in patients with implanted ICD and CRT-D devices. It should be kept in mind that in those patients with CRT-D, rate responsive mode is on; inappropriate sinus tachycardia can be seen during EECP therapy. Also in patients with CRT-D using a unipolar sensing mode, problems of QRS complex sensing by the EECP may occur and, therefore, this effects synchronization and success of EECP therapy.

During sinus rhythm, anesthetized pigs (38 ± 6 kg) received an S-ICD (n = 4) and five 80-Joule (J) shocks, or a transvenous ICD (control, n = 4) and five 35-J shocks. An inactive S-ICD electrode was implanted into the same control pigs to study implant trauma. All animals survived 24 hours. Troponin I and creatine kinase muscle isoenzyme (CK-MM) were measured as indicators of myocardial and skeletal muscle injury. Histopathological injury of heart, lungs, and chest wall was assessed using semiquantitative scoring.

Troponin I was significantly elevated at 4 hours and 24 hours (22.6 ± 16.3 ng/mL and 3.1 ± 1.3 ng/mL; baseline 0.07 ± 0.09 ng/mL) in control pigs but not in S-ICD pigs (0.12 ± 0.11 ng/mL and 0.13 ± 0.13 ng/mL; baseline 0.06 ± 0.03 ng/mL). CK-MM was significantly elevated in S-ICD pigs after shocks (6,544 ± 1,496 U/L and 9,705 ± 6,240 U/L; baseline 704 ± 398 U/L) but not in controls. Electrocardiogram changes occurred postshock in controls but not in S-ICD pigs. The myocardium and lungs were histologically normal in both groups. Subcutaneous injury was greater in S-ICD compared to controls.

Although CK-MM suggested more skeletal muscle injury in S-ICD pigs, significant cardiac, lung, and chest wall histopathological changes were not detected in either group. Troponin I data indicate significantly less cardiac injury from 80-J S-ICD shocks than 35-J transvenous shocks.

From August 2008 to January 2010, 173 prospective, consecutive patients underwent LLE in a single center. All patients had transesophageal echocardiograms (TEE) during the extraction. Fifty-three patients had tricuspid valve function evaluated a day before the procedure with a transthoracic echocardiogram (TTE), during the procedure with a TEE and 2 days postoperatively with a TTE.

All 173 patients experienced no change in tricuspid valve function during the procedure with TEE. Of the 53 patients who underwent a complete TI evaluation, 38 were males (72%) and 15 females (38%), with a mean age of 69.45 ± 14.08. Mean ejection fraction was 35.82 ± 14.72. Three (6%) patients experienced TI after the procedure (two mild and one severe, all with tricuspid valve endocarditis); 16 (30%) patients were found to have TI before LLE that returned to normal valve function during or after the procedure. Thirty-four (64%) patients did not experience any significant change of the tricuspid valve performance after LLE.

LLE was not associated with increased TI.

For each patient, CO was measured in “no-pacing” and in all the 10 configurations available, within 7 days of implantation of the device. Tip-ring, tip-right ventricular coil (RVC), and ring-RVC vectors were considered as traditional vectors. The seven additional configurations available in the quadripolar lead were considered as nontraditional vectors. CO was measured by ECHO. The best configuration was defined as the one presenting the highest CO measurement within configurations, which have a capture threshold <3 V and a safety margin between the capture and the phrenic nerve stimulation thresholds.

Fifty-one standard cardiac resynchronization therapy patients were enrolled. The mean of each patient's best CO obtained with traditional vectors was higher than the baseline nonpaced CO (4.16 L/min vs 3.64 L/min). The mean of each patient's best CO, including all 10 available configurations, was also higher than the baseline nonpaced CO (4.33 L/min vs 3.64 L/min). In addition, the mean of each patient's best CO obtained with the best configuration available through a quadripolar lead was better than the mean of each patient's best CO obtained with a traditional configuration. In 53% of patients, the best CO was obtained with a nontraditional vector unique to the quadripolar lead.

A quadripolar lead offers multiple additional pacing options to increase CO acutely compared to conventional bipolar leads.

The studied active-fixation, steroid-eluting lead (Linox^smart S DX, BIOTRONIK SE & Co KG, Berlin, Germany) is one French thinner than its predecessor and coated with lubricious SilGlide to improve lead handling. A dedicated ICD device has a self-adaptive atrial input stage including a fourfold amplifier. The amplification, filtering, and adapted atrial input stage are located in the Lumax 540 VR-T DX (BIOTRONIK). The Linox^smart S DX ICD lead delivers only the signal. The lead was evaluated during implantation; at predischarge; and 1-, 3-, and 6-month follow-up examinations. The primary endpoint (efficacy) was the rate of appropriate atrial sensing tests. The secondary endpoint (safety) was freedom from lead-related invasive reinterventions. Both safety and efficacy were expected to be significantly higher than 90%.

The study enrolled 116 patients at 25 clinical sites. Skin-to-skin operation time was 52.4 ± 26.2 minutes. The investigators graded lead insertion as “easy” in 87% of patients. Mean P-wave amplitudes (preamplified) varied from 5.0 to 6.1 mV in different body positions. Both primary and secondary endpoints were met, as 93.8% (364/388; P = 0.005) of specific sensing tests indicated appropriate atrial sensing, and 94.8% (110/116; P = 0.048) of patients were free from reinterventions (lead dislodgement). Analysis of arrhythmia episodes stored in ICDs and elective 24-hour Holter electrocardiogram tests raised no concerns about lead functionality.

The studied ICD lead with a floating atrial sensing dipole met the predefined safety expectation and demonstrated appropriate atrial sensing performance.

One hundred and one patients, 41 with pacemakers and 60 with ICDs, were enrolled (mean age 66 ± 15 years). Four avalanche transceivers (Pieps DSP [Pieps GmbH, Lebring, Austria], Ortovox x1, Ortovox m2, and Ortovox f1 [Otovox Sportartikel GmbH, Taufkirchen, Germany]) were evaluated in transmit as well as in receive mode. Surface electrocardiograms, intracardiac electrograms, and marker channels were continuously recorded and observed by an experienced physician. Electromagnetic interference events were categorized as direct interference with the function of the implanted device itself or as interference with the telemetric communication without compromising device function.

Among all patients, there was no interference with the intrinsic function of their pacemakers or ICDs. A total of 120 episodes of telemetry interference occurred in 48% of the patients. Of those episodes, 112 of 404 (28%) were observed in transmit and eight of 404 (2%) in receive mode (P < 0.0001). The digital avalanche transceiver (Pieps DSP) was associated with significantly less telemetry interference (20/202; 10%) than the analog transceiver (Ortovox f1) (39/202; 19%) (P = 0.0108).

Avalanche transceivers are safe for patients with pacemakers and ICDs. Despite the observed telemetry interferences, the intrinsic function of the implanted devices was never compromised.

A total of 210 patients with LPeAF referred for catheter ablation were enrolled and randomized into three ablation groups. The patients in group A (n = 70) underwent PVI followed by LA linear and CFAE ablation; in 93% of patients the primary endpoint was achieved (five patients with incomplete linear lesions). Of the 70 patients in group B who were subjected to PVI followed by LA linear, CFAE, and CTI ablations, in 94% of patients the primary endpoint was achieved (four patients with incomplete linear lesions). All patients in group C (n = 70) successfully underwent PVI and CFAE ablation. Direct current cardioversion was performed upon PVI, CFAE elimination, and completion of linear lesions. Patients were followed-up for atrial tachyarrhythmia recurrence for at least 24 months. After a single ablation procedure, group C (36%) exhibited the lowest success compared with group A (54%) and group B (51%) (P = 0.06). At the mean follow-up of 32 ± 9 months after the final ablation procedure, 53 patients (76%) in group A, 53 (76%) in group B, and 41 (59%) in group C were in sinus rhythm without antiarrhythmic drugs (P = 0.03).

In LPeAF, linear lesions in the LA help improve outcome of ablation, additional CTI ablation does not.

In 79 consecutive patients, who were referred for catheter ablation of symptomatic paroxysmal or persistent atrial fibrillation (AF), the presence of a PFO was explored by MDCT and transesophageal echocardiography (TEE). TEE was considered as the gold standard, and quality of TEE was good in all patients. In 16 patients (20.3%), MDCT could not be used for analysis because of artifacts, mainly because of AF. On TEE, a PFO was found in 15 (23.8%) of the 63 patients with usable MDCT. MDCT detected six PFO of which four were present on TEE. This corresponded to a sensitivity of 26.7%, a specificity of 95.8%, a negative predictive value of 80.7%, and a positive predictive value of 66.7%. The receiver operating characteristics curve of MDCT for the detection of PFO was 0.613 (95% confidence interval 0.493–0.732).

MDCT may detect a PFO before pulmonary isolation. However, presence of AF may lead to artifacts on MDCT impeding a meaningful analysis. Furthermore, in this study sensitivity and positive predictive value of MDCT were low and therefore MDCT was not a reliable screening tool for detection of PFO.

This was a retrospective analysis of 1,550 consecutive patients with ICD implantation at a single center from 1996 to 2008 with a mean of 4.2 ± 3.4 years. Patients with implant intrinsic heart rates less than 40 beats/min (n = 48) and cardiac resynchronization therapy (n = 444) were excluded leaving 1,058 patients in this study. PD was defined as an intrinsic rhythm <40 beats/min after inhibiting the pacemaker, <50 beats/min with transient symptoms of dizziness relieved by resumption of pacing and right ventricle pacing despite algorithms to promote intrinsic conduction at the 3 monthly follow-up ICD clinic visits. Multivariate regression and Cox proportional hazard models were used for analysis.

The mean age was 64 ± 13 years; 79% were male with a primary indication for the ICD in 57%. PD occurred in 142 (13.4%) of patients, with a mean time to PD of 2.6 ± 1.9 years. PD was associated with a 48% increased odds for mortality versus non-PD ICD patients during the mean follow-up time of 4.2 ± 3.4 years (adjusted odds ratio = 1.48 [95% confidence interval 1.080–2.042]; P = 0.015). Older age, a history of atrial fibrillation, amiodarone use, and secondary prevention were the strongest predictors for the development of PD.

In this single-center ICD cohort, the development of PD was not uncommon and was associated with decreased survival.

Nine patients who underwent epicardial ICD implantation were included. The median age was 7.4 years (3.9–9.6 years) and the median weight was 15 kg (12–24 kg). Diagnosis at the time of implantation included long QT syndrome (n = 5), catecholaminergic polymorphic ventricular tachycardia (n = 2), hypertrophic cardiomyopathy (n = 1), and fast monomorphic ventricular tachycardia (n = 1). The minimally invasive method involved a subxiphoid incision to place the epicardial pacing leads. The ICD coil was placed in the transverse sinus in four patients using an access path posterior to the heart. The second approach involved a path anterior to the heart to reach the epicardial location posterior to the left atrial appendage in the five remaining patients. No fluoroscopy was used in either approach. The median defibrillation threshold (DFT) at implantation was 7.5 J.

Lower DFTs were observed in the anterior approach (10 J vs 5 J). Appropriate ICD shocks were observed in three patients during the median 18-month follow-up period (0.3–28 months). No inappropriate shocks were noted. One patient developed pericardial tamponade 39 days after the procedure and was surgically drained.

Minimally invasive epicardial ICD coil implantation in children with low DFT values is possible. The anterior implantation approach appears superior to the posterior approach.

Data on 16 newborns with congenital complete atrioventricular block (CCAVB) implanted with a SJM Microny pacemaker between January 1998 and December 2004 were collected. The ERS at discharge, at 12 ± 2 months, and long-term AC performance were analyzed retrospectively. The median follow-up time was 5.3 years (range 0.4–8.6 years), the end point of follow-up being either lead or generator exchange.

AC could be activated in all patients at discharge; the median ERS was 9.3 mV (3.7–19.0 mV). At 12 ± 2 months, the median ERS measured 4.6 ± 3.6 mV (n = 13), showing a significant decrease (P = 0.002) and leading to discontinuation of AC in three (23%) of 13 patients. AC use was possible in eight patients and long-term use in six patients.

In epicardially paced CCAVB newborns, the ERS amplitude decreased significantly during the first year. ERS decrease was the most common reason for AC failure. At 1-year follow-up, AC was functional in only 53% of patients, although it could originally be activated in all patients. During the first year of follow-up, special attention to AC parameters is recommended in this subgroup of pediatric pacemaker patients.

We reviewed 750 open heart surgeries (OHS) for CHD performed between January 2005 and February 2009. Kaplan-Meier and Cox proportional hazards model analyses were used to estimate the frequency and evaluate risk factors that might predict JET occurrence.

The patients ranged in age from 1 day to 36.6 years; half were less than 4.8 months at the time of OHS. JET occurred in 115 of 750 (15.3%) OHS. JET was bimodally distributed by age with a peak incidence between 1–2 weeks and 1–3 years. JET occurred more commonly: (1) in specific types of OHS (single ventricle [19.5%] and cono-truncal defects [19.3%]) (P = 0.03); (2) with increased total surgical time (P = 0.001), aortic cross-clamp time (P < 0.001), cardiopulmonary bypass time (P < 0.001); and (3) followed use of inotropic agents (dopamine or milrinone, P < 0.001). JET lengthened intensive care stay by 3 days (P = 0.0001) and increased mortality (+JET [9.6%] vs –JET [4.6%], P = 0.03). In a multiple variable Cox regression model, total surgical time and PO use of milrinone were the best predictors for JET risk. PO administration of nitroprusside decreased risk of JET.

JET occurred more commonly following OHS associated with prolonged surgical times and PO use of inotropic medications. In contrast to previous reports, our results suggest that mechanical injury to the atrioventricular node area is not strongly associated with JET.

We compared the patient characteristics and clinical outcomes of 600 consecutive patients who underwent different blind axillary vein puncture procedures. In group I, a steep needle puncture method was used, whereas in group II a shallow needle puncture technique was used.

The shallow needle puncture method was associated with a higher success rate than the steep needle puncture method (94% vs 54%, P < 0.00001). The shallow needle puncture method was also associated with a much shorter puncture and lead insertion time (7 ± 2 minutes vs 10 ± 3 minutes, P = 0.02).

Our shallow needle puncture technique does not require any extra equipment. In addition, this method is effective and safe and may be used as the initial attempt for venous access during pacemaker implantation.

Complete AV block was induced in adult dogs who had undergone implantation of backup electronic pacemakers. cMSCs were transfected with mHCN4 genes. Evidence of successful I_HCN4 expression was provided by patch-clamp detection. mHCN4-cMSCs or normal cMSCs were injected subepicardially into the left ventricular anterior wall of the dogs. Cardiac parameters were monitored for 6 weeks. Heart rate variability (HRV) was evaluated using quantitative Poincaré plots of R-R_N against R-R_N+1 intervals. cMSCs survival and expression of HCN4 in vivo were examined by histological studies and Western blot.

In 2 weeks, the maximum heart rate and the number of impulses generated from the injection sites were much higher in dogs injected with HCN4-modified MSCs than in control dogs.  Basal heart rate increased in the HCN4 group and became fully stabilized by Week 4, evidenced by markedly reduced numbers of electronic pacemaker beats. At Week 2, HRV during exercise was significantly higher in HCN4 dogs than in controls as shown by descriptors of both instantaneous (SD1) and longer term (SD2) beat-to-beat deviations (P < 0.05). Hematoxylin-eosin staining and Western blot proved that cMSCs survive and express HCN4 protein in situ in heart of HCN4 dog.

Transplantation of mHCN4-modified cMSCs provided a stable biological pacemaking function that allowed an appropriate chronotropic response to physical exercise for up to 6 weeks.

Laser radiation at 15 W or 20 W was applied in blood for 10 seconds, 20 seconds, 30 seconds, 40 seconds, and 50 seconds during an irrigation flow of 16 mL/min or 35 mL/min, in direct contact, and in a noncontact mode of laser application. Lesions were evaluated morphometrically.

There was a linear increase of lesions with the increase of the level of energy applied. Maximal depth of lesions achieved during a flow rate of 16 mL/min at 15 W/50 seconds increased significantly from 9.9 ± 0.3 mm to 12.1 ± 0.5 mm, and at 20 W/50 seconds from 11.1 ± 0.55 mm to 12.4 ± 0.26 mm, when irrigation flow was 35 mL/min (P < 0.5). However, difference of lesion increase between 15 W and 20 W was not significant (P = 0.30). Lesions were achieved also in a noncontact mode of radiation at a distance of 1–2 mm, but not at 5 mm away. Radiation at 20 W > 40 seconds and a flow rate of 35 mL/min may cause steam pop with intramural cavitation.

By using an open-irrigated laser catheter augmentation of catheter flow increases lesion sizes. Lesions can be achieved also in a noncontact mode of radiation. In order to avoid unwanted effects the level of energy applied must be limited.

This study was a retrospective analysis of the case records of all patients referred to our institution for transvenous retrieval of intravascular foreign objects.

Over 10 years, 45 consecutive patients underwent procedures for the retrieval of intravascular foreign objects. These objects were: 25 distal portions of introducer sheaths, 18 pacing lead fragments, one guidewire, and one anchoring sleeve. The majority of fragments were located in the right ventricle and subclavian and caval veins. Some had migrated to the pulmonary artery or more distally. The median dwell time of the fragments was 3 months. Retrieval was most frequently achieved through the femoral veins, and was successful in 42 (93%) procedures. No procedure-related complications occurred in this series.

In the present single-center experience, the endovascular approach to retrieving intravascular objects lost during cardiac device implantation or previous extraction procedures seemed effective with currently available tools and was associated with no complications.

We searched PubMed, EMBASE, CINAHL, and Cochrane Central Register of Controlled Trials’ databases for randomized controlled trials conducted between 1990 and 2011 that assessed rates of POAF with amiodarone. Finally an interaction odds ratio was computed to assess the efficacy of an oral-only regimen of amiodarone compared to one including IV administration and to evaluate if preoperative amiodarone was superior to postoperative prophylaxis.

Twenty-three studies (total N = 3,950) were included. Both regimens of amiodarone improved risk of POAF; oral-only risk ratio (RR) was 0.59 (95% confidence interval [CI] 0.49–0.70; P < 0.01) and regimen including IV RR was 0.57 (95% CI 0.43–0.75, P < 0.01). The interaction odds ratio was 1.17 (95% CI 0.72–1.89, P = 0.533). Both preoperative amiodarone (P < 0.01) and postoperative prophylaxis were effective (P = 0.0009), irrespective of duration.

This systematic review suggests a regimen of both oral-only and one including IV administration, as well pre- and postoperative administration of amiodarone is effective in prevention of POAF after cardiac surgery.

We conducted a retrospective chart review of 415 consecutive patients who underwent ICD implantation for prevention of SCD between 2007 and 2010. Patients were divided into an outpatient group (Group A) and an inpatient group (Group B). We evaluated the patients’ demographics, comorbidities, and the rate of short-term surgical complications on or before the 2-week follow-up appointment.

Of 252 patients included in Group A, 198 (78.6%) were successfully discharged on the same day (Group A1). At the 2-week wound check appointment, four patients (2%) had minor surgical site bleeding, one patient had a hematoma, and one patient developed fever and swelling around the implantation site. Of the Group A patients, 54 (21.4%) were not discharged on the same day (Group A2). A total of 53 patients were included in Group B, four (7.5%) developed a hematoma at the 2-week follow-up wound check visit.

Procedure-related complications after ICD placement are rare. Same-day discharge is safe and feasible following ICD placement for primary prevention of SCD and hence a reduction in healthcare costs can be achieved by decreasing the length of hospital stay.

Retrospective study performed on patients with preexcitation who underwent an electro-physiological study (EPS). IPX was defined as loss of the delta wave on electrocardiogram prior to EPS. Patients with IPX were compared with those with persistent preexcitation (PPX) or suppression of the delta wave on exercise test (IPX-ET). Congenital heart disease and prior ablations were excluded.

Of 328 patients with preexcitation, 41 (12.5%) had IPX. Patients with IPX or PPX were similar in age (12.9 years vs 13.0 years, P = 0.8) and AP location (left-sided 54% vs 50%, P = 0.7; septal 32% vs 35%, P = 0.4). Testing on isoproterenol was performed in 17 (41%) IPX and 41 (14%) PPX patients. Although IPX patients had a longer median refractory period compared to PPX patients (340 ms vs 310 ms, P = 0.001), the incidence of APs with refractory periods ≤250 ms was similar (10% vs 12%, P = 1.0). Exercise tests were performed on 208 patients and 24 (12%) had IPX-ET. Compared with IPX patients, IPX-ET had similar median AP refractory periods (320 ms, P = 0.4) and incidence of APs with refractory periods ≤250 ms (13%, P = 1.0).

Patients with IPX had longer AP refractory periods than those with PPX, but the incidence of pathways with refractory periods ≤250 ms was not significantly different. The finding of IPX on a baseline electrocardiogram does not rule out potentially high-risk pathways.

Patients with standard guidelines-based ICD indications were enrolled and implanted with a St. Jude Medical™ DF4 system (St. Jude Medical, Sylmar, CA, USA; right ventricular high-voltage DF4 lead models 7120Q, 7121Q, 7122Q, or 7170Q with compatible ICD). Device electrical measurements, handling characteristics, and any adverse events were collected at implant and during each scheduled 6-month follow-up.

Among 1,701 patients (65 ± 13 years, 72% male, left ventricular ejection fraction 29 ± 12%) enrolled at 58 centers, there were 1,697 successful implants (99.8% implant success; ICD; n = 999, cardiac resynchronization therapy-defibrillator n = 698). Implanting physicians reported that implantation of the DF4 lead was normal or easier than normal in 94% of cases with successful implant. These patients have been followed for 1.7 ± 0.5 years with a maximum follow-up of 2.5 years. The complication rate was 0.017 per patient year of follow-up (95% confidence interval: 0.013–0.023), which included abnormal defibrillation impedance, elevated pacing thresholds, failure to detect ventricular tachycardia/ventricular fibrillation, lead dislodgement, lead fracture, loss of capture, and lead perforation. There were no set screw-related complications at implant or during follow-up.

The DF4 system overall performed very well with few complications at implant and in follow-up.

We identified 1,445 consecutive patients undergoing ICD implantation from 1997 to 2007. The study population consisted of 582 patients, of whom 291 were women who could be propensity matched to 291 men, based on age, ejection fraction, implantation indication (primary or secondary), etiology of cardiomyopathy (ischemic or nonischemic), and the presence of a cardiac resynchronization therapy-defibrillator (CRT-D) device. The impact of gender difference on the probability of death and appropriate ICD shocks for ventricular arrhythmias was calculated using multivariable Cox proportional hazards analyses.

During a mean follow-up of 909 ± 901 days, compared to men, women demonstrated a similar risk of death (25% vs 25%, adjusted hazard ratio [AHR] 1.05 [95% confidence interval (CI) 0.81–1.35], P = 0.74). In contrast, women demonstrated a decreased probability of appropriate ICD-shock therapy (14% vs 19%, AHR 0.80 [95% CI 0.59–0.88], P = 0.03) compared to men, and among cohorts with a nonischemic cardiomyopathy (10% vs 20%, P < 0.001) and CRT-D devices (7% vs 19%, P = 0.01).

Among a community cohort with ICDs, women have a similar mortality compared to men while experiencing less appropriate ICD therapy. These results support the findings of a lower arrhythmic mortality among women.

In 10 pigs, catheters in the right atrium (RA) and right (RV) and left ventricle (LV) allowed pacing and recording of monophasic action potentials (MAP). During RA pacing at stable 500-ms CL, LV was paced at alternating CL (505 ms and 495 ms). Changing the alternating LV (A-LV) pacing delay changes the size of the region with alternating ventricular activation. Spectral analysis of intracardiac MAP was correlated with body surface MTWA. In a similar setup (during alternating pacing in RV and LV), we investigated concordant versus discordant APD alternans.

Pacing the LV with subtle alternating cycle lengths at short A-LV delay leads to broad QRS (97 ± 10 ms), body surface MTWA (mean V_alt 4.2 ± 1.8 µV), and positive RR-interval alternans. At longer A-LV delay, not resulting in QRS widening (68 ± 5 ms), body surface RR alternans was absent but MTWA remained detectable and was even more pronounced (8.7 ± 5.1 µV, P < 0.01). During both concordant and discordant pacing MTWA was present. The precordial leads were better for detecting discordant APD alternans (8.0 ± 2.9 µV and 12.8 ± 4.52 µV, P = 0.02).

MTWA is a potent technique to detect subtle and isolated intracardiac APD alternans that is artificially induced by alternating pacing. In the same model, discordant activation alternans can only be discriminated from concordant when using a quantifying approach of MTWA analysis.

Retrospective analysis based on medical records of the consecutive 3,288 cardiologic outpatients (mean age, 61 ± 12 years; 43% men).

A total of 254 patients (7.7%) reported emotional VVS, whereas 294 (9.0%) had history of orthostatic VVS. First-ever syncopal episode was reported at a median age of 16 years (interquartile range [IQR], 12 years to 28 years), and the median total number of episodes was two (IQR, 1 to 5). There were 779 patients (23.7%) with at least one CV event, and the median age for the first CV event was 59 years (IQR, 52 years to 67 years). In the fully adjusted model, history of emotional VVS was predictive of CV event (hazard ratio [95% confidence interval]: 1.63, [1.27–2.09]; P < 0.001), myocardial infarction (1.99, [1.49–2.66]; P < 0.001), and percutaneous coronary intervention (1.84, [1.31–2.60]; P = 0.001). There was one significant interaction (P = 0.07) between history of emotional VVS and gender. Emotional VVS was predictive of CV event in men (1.89 [1.41–2.53]; P < 0.001) but not in women (1.24 [0.79–1.94]; P = 0.35).

History of emotional but not orthostatic VVS is independently associated with increased risk of coronary events in later life. The relationship between predisposition to emotional VVS in adolescence and development of cardiovascular disease requires further studies.

We retrospectively collected data on PPM implantations after TAVI in our center from January 2010 to December 2012. In total, we included 30 patients who received a PPM for TAVI-related AV block. Twelve patients (group A) underwent PPM implantation on the day of TAVI. In 18 patients (group B), PPM implantation was performed at least 1 day after TAVI (3.8 ± 4.5 days). Since all patients undergoing TAVI receive dual antiplatelet therapy (DA-therapy), we compared all implantations after TAVI with a historic patient cohort that underwent PPM implantation under DA-therapy.

Procedure times, fluid loss via drainage systems, and drainage times were neither significantly different between groups A and B nor between all PPM implantations after TAVI compared to the historic control group.

PPM implantation immediately after TAVI is safe and can be performed without increased rate of complications.

The effects of nifekalant on AFL were elucidated in 17 patients. During AFL, the conduction time from the lateral to septal cavotricuspid isthmus (IS) and that through the reminder of the right atrium (nIS); AFL-cycle length (CL) variability, which was quantified by the standard deviation; and the maximum difference in AFL-CL were measured before and after administration of nifekalant (0.2–0.3 mg/kg). A single extrastimulus was delivered from the lateral cavotricuspid isthmus to elucidate the resetting response curves and atrial effective refractory period (AERP) before and after administration of nifekalant.

There was no significant difference in AFL-CL, IS, and nIS before and after nifekalant; however, AERP was increased after nifekalant (155 ± 22 ms vs 184 ± 32 ms, P < 0.001). The standard deviation and the maximum difference in AFL-CL were both increased after nifekalant (1.7 ± 0.7 ms vs 3.6 ± 2.3 ms, P < 0.001 and 4.1 ± 1.9 ms vs 8.5 ± 5.2 ms, P < 0.001). The total excitable gap decreased (94 ± 17 ms vs 66 ± 21 ms, P < 0.001) with rightward shift of the resetting response curves and loss of full excitability after nifekalant. In 11 patients (65%), AFL was terminated spontaneously (n = 7) or by a single extrastimulus (n = 4), which was not observed before nifekalant. Termination was associated with orthodromic block in the cavotricuspid isthmus in all patients.

Nifekalant increases AERP and AFL-CL variability by abolishing a fully excitable gap, without prolongation of AFL-CL. These unique effects facilitate the termination of AFL.

We conducted a cohort analysis of 175 patients (138 men; age range 57–79 years) who underwent CRT implantation during 2004–2008 in our institution. AF was documented in 66 patients (37.7% of patients, 52 men). There were no differences in 1- or 2-year mortality between patients with and without AF (13.6% vs 11.79%, P = 0.7; 25.8% vs 16.9%, P = 0.2, respectively). There were no differences between the groups in the rate of complications after CRT implantation or in the rate of appropriate electrical shocks. In the subgroup of AF patients with cardiac resynchronization therapy defibrillator (CRT-D) (n = 32, 48.5%), the 1-year mortality was 3.1% as compared to 23.5% in AF patients with cardiac resynchronization therapy pacemaker (P = 0.03). This difference was no longer evident after 2 years (25.0% vs 26.5%, P = 0.8, respectively). Ten patients (15.2%) with AF underwent atrioventricular (AV) node ablation. The 2-year mortality of these patients was 10.0% as compared to 28.6% in AF patients who did not undergo AV-node ablation (P = 0.4).

In this study, no difference in mortality appears to exist between patients with or without AF and who undergo CRT implantation. Our findings of the beneficial effects of AV-node ablation and CRT-D in AF patients deserve further investigation.

After the Spanish centers performing CRT were identified, data were recorded voluntarily by each implantation team from September 2010 to September 2011.

A total of 88 implanter centers were identified, and of these 85 (96.5%) answered the questionnaire. In total, 2,147 device implantations were reported, comprising 85% of the Eucomed's overall estimate for the same period, which was 2,518 implantations. Centers handling a higher volume of implants have a higher percentage of patients referred from other centers and more indications in patients over 80 years of age, with atrial fibrillation (AF), right bundle branch block, and unspecific disorders of intraventricular conduction. These high-volume centers stimulate more frequently in patients with very wide QRS > 200 ms. Lower-volume centers select more classic patients for resynchronization, whereas higher-volume centers increase the rate of patients with AF and prior cardiac stimulation (upgrade). Implant duration is shorter for higher-volume centers, which also perform implants in patients with congenital heart disease. By contrast, there are no significant differences in terms of heart disease, device type (pacemaker or defibrillator), implant techniques, achieved optimal site location, or complications.

High-volume centers perform CRT more frequently in elderly patients, mostly with AF and other alternative implants. No significant differences were found between the complications reported by high-volume centers and those reported by low-volume centers.

This was a retrospective study of all patients at a single center with an endocardial OptiVol capable device. OptiVol index values were collected in 2-week bins from January 2007 to December 2010. The clinical outcomes were CHF exacerbation defined as hospitalization or medication change for CHF and device-treated ventricular arrhythmia based on remote or in-office device interrogation. Clinical and OptiVol data were collected by separate investigators blinded to the other parameter. OptiVol data were correlated to the clinical outcomes to determine sensitivity and predictability for multiple threshold values in the entire cohort and pediatric and congenital subgroups.

Forty-seven patients were included. A total of 1,106 months of OptiVol data were collected. Median age of the cohort was 18 years (range 6–58 years). There were 23 pediatric, median age 13 years (range 6–16), at device implant, and 18 patients, median age 31 years (range 13–58), considered at risk for heart failure at implant. There were three heart failure exacerbations and 17 treated ventricular arrhythmias. The study population-specific positive predictive value (PPV) of OptiVol was low (sensitivity 33% and PPV ≤4.4%) for both CHF exacerbation and arrhythmias in all analyzed groups.

The sensitivity and positive predictive value of intrathoracic impedance monitoring was low in this population of adult congenital and pediatric patients. Recent improvements to the OptiVol algorithm may decrease these deficiencies.

The study population consisted of 156 paroxysmal AF patients who underwent first time PVI and were found to have spontaneous DiFi from the pulmonary veins (PVs). Their outcomes were compared to a population of 156 propensity-matched controls from our prospectively maintained AF ablation data registry.

DiFi was most frequently observed from the right superior PV and occurred in 89 patients (57.1%). After 24 months of follow-up, patients with DiFi had better success rates compared to those with silent veins after isolation (88.5% vs 75%, P = 0.002). The overall distribution of types of recurrent arrhythmia was similar between DiFi patients and their matched controls (P = NS). During repeat ablations, DiFi patients were less likely to have PV conduction recovery (60% vs 93.3%, P = 0.02). Importantly, none of the veins with DiFi during index procedures was found to have conduction recovery.

In patients with paroxysmal AF undergoing ablation, DiFi from the PVs after their isolation was associated with improved ablation outcomes. It is possible that DiFi is an indicator of successful durable isolation of the PVs. The findings suggest that confirmation of exit block may be warranted to improve AF ablation outcomes.

Of 72 patients (58 males, 65 ± 13 years) with typical AFL, 19 were classified as type 1 and 53 as types 2 and 3. We created an electroanatomic map of the right atrium (RA) during AFL and determined which RA site activation corresponded to which F-wave component by analyzing the activation map. It was revealed that F-wave component from the nadir to terminal deflection point coincided with the cranio-caudal activation of the RA free wall (RAFW) in all types. The bipolar voltage map showed that type 1 had the greater extent of low voltage (<0.5 mV) area (LVA) in RAFW (39 ± 24%) than types 2 and 3 (4 ± 3%) (P < 0.0001), explaining the absence of PTD in type 1. In types 2 and 3, F-wave amplitude determining the PTD magnitude was highly correlated with the longitudinal distance between two points on RAFW corresponding to the nadir and peak of F-wave (r = 0.73, P < 0.0001).

Terminal positivity and amplitude of F-wave in typical AFL are primarily related to the RAFW activity: negatively by the extent of LVA and positively by the longitudinal vector of activation.

Triggering structures inducing PAF were identified during isoproterenol challenge in 26 patients (15 males, 55 ± 8.5 years). During sustained PAF, sequential recordings were made with a decapolar circular mapping catheter from each PV and the left atrial posterior wall (LAPW), together with coronary sinus (CS) and right atrium (RA) recordings. DF was determined using fast Fourier transformation. Recordings were repeated after ≥15 minutes of PAF. Radiofrequency ablation was directed first at the triggering PVs. PAF initiated from the PVs in 24 patients and from RA in two. There was a significant frequency gradient from the triggering structure to the PVs, CS, LAPW, and RA (P < 0.0001). During the second recording, DF decreased at all sites (P < 0.02), but the frequency gradient remained unchanged. Despite isolation of the triggering PV, PAF continued in 53% of patients, although DF measured in the CS was lower. AF termination occurred with contralateral PV isolation in half of the remaining patients and further AF slowing was noted in the rest.

Triggering structures harbor the fastest activity during sustained PAF pointing to their leading role in arrhythmia perpetuation. However, nontriggering PVs also seem to contribute to PAF maintenance.

Between April 2005 and March 2012, 208 consecutive LE procedures were performed and 456 leads were extracted using an initial superior approach. Advanced techniques for LE (step 4 according to our stepwise approach) were used in 122 patients (58.7%).

Younger patient age (odds ratio [OR] = 0.963, P = 0.002), longer duration of the initial implantation (OR = 1.013, P = 0.002), the number of extracted leads (OR = 2.184, P < 0.001), and the presence of right ventricular defibrillator leads (OR = 2.144, P = 0.049) independently predicted the necessity of using step 4 in multivariate analysis. A prediction tool was created taking into account four categorical variables derived even from Receiver Operating Curve analysis of quantitative characteristics (age < 70.7 years, implant duration > 37 months, extraction of at least two leads, one of them being a defibrillator lead). The absence of all the four characteristics was accompanied by 0% positive predictive value for the requirement of step 4 for LE, whereas the coexistence of all four risk factors is characterized by 87% requirement of advanced LE.

In most of the patients with indication for LE, use of a powered sheath extraction is necessary in order to obtain clinical success. We have identified four patient and lead characteristics that may help the operator plan the means of extraction.

Twenty-four patients (18 women, 41 ± 13 year olds) were diagnosed with IST according to current guidelines criteria. Patients were treated with 5–7.5 mg of ivabradine twice a day. Twenty-four-hour Holter recordings and the SF-36 Health Survey were performed at 6 months to evaluate both HR control and clinical status.

Holter recordings before and after 6 months on treatment showed a significant reduction in the average maximal HR of 155 ± 18 beats/min versus 132 ± 16 beats/min, mean HR of 97 ± 6 beats/min versus 79 ± 8 beats/min (mean daytime HR of 103 ± 8 beats/min vs 84 ± 10 beats/min) and minimal HR of 58 ± 12 beats/min versus 48 ± 7 beats/min (Wilcoxon analysis, P < 0.05). The SF-36 mean score showed a significant improvement on ivabradine treatment (57 ± 23 vs 76 ± 20), with a better physical and mental status scores (56 ± 25 vs 74 ± 22 and 58 ± 24 vs 78 ± 18, respectively) (Wilcoxon analysis, P < 0.001). Mean dose of ivabradine was 5.8 ± 1.4 mg. No episodes of severe bradycardia or syncope were reported. After 1 year, patients were asked to stop treatment to reevaluate the situation. Twenty patients were on treatment and only 10 patients accepted to stop ivabradine. Only two patients (20%) remained on IST criteria.

IST patients treated with ivabradine showed both HR normalization and quality-of-life improvement maintained in the long-term follow-up. Stopping ivabradine after 1 year unexpectedly showed that HR remained in the normal limits in 80% of the patients.

A catheter with two platinum electrodes spaced 3 mm apart was used as the dipole source in the phantom study. A 40-Hz sinusoidal signal was applied to the electrode pair. In the animal study, four to eight electrodes were sutured onto the right ventricle. These electrodes were connected to a stimulus generator delivering 1-ms duration pacing pulses. Signals were recorded from 64 electrodes, located either on the inner surface of the saline tank or on the body surface of the pig, and then processed by the ISGA to localize the physical or bioelectrical SEMD.

In the phantom studies, the guidance algorithm was used to advance a catheter tip to the location of the source dipole. The distance from the final position of the catheter tip to the position of the target dipole was 2.22 ± 0.78 mm in real space and 1.38 ± 0.78 mm in image space (computational space). The ISGA successfully tracked the locations of electrodes sutured on the ventricular myocardium and the movement of an endocardial catheter placed in the animal's right ventricle.

In conclusion, we successfully demonstrated the feasibility of using an SEMD inverse algorithm to guide a cardiac ablation catheter.

One hundred fifty-three patients with a diagnosis of nonvalvular AF and 150 age-matched control subjects with sinus rhythm were recruited. SQ was assessed using the Pittsburgh Sleep Quality Index (PSQI). The study was designed with two stages. First, the difference in SQ between AF patients and age-matched controls was examined. Patients with global PSQI scores greater than 5 were defined as “poor sleepers.” Thus, a higher global PSQI score indicated worsened SQ. Predictors of poor SQ were also analyzed using a regression model. Second, the effect of rhythm control on SQ was studied in patients with AF who were eligible for DCC. Of the 65 patients with persistent AF, 54 patients with successful cardioversion were followed for 6 months. The remaining 11 patients, whose cardioversion was unsuccessful, were not followed. After 6 months of follow-up, the PSQI scores of patients with sinus rhythm maintenance (n = 39) and patients with AF recurrence (n = 15) were reassessed. Changes in global PSQI scores (baseline vs after 6 months) were analyzed.

The PSQI scores were significantly higher in the AF group compared to the control group (9.4 ± 4.6 vs 5.8 ± 4.1, P = 0.001, respectively). The prevalence of poor sleepers was significantly higher in the AF group (76%) than in the control group (45%) (P < 0.001 by the χ² test). Multivariate logistic regression analysis showed that AF (odds ratio [OR]: 3.36, 95% confidence interval [CI]: 2.00–5.55), age (OR: 1.02, 95% CI: 1.00–1.04), and diabetes mellitus (OR:1.79, 95% CI: 1.03–3.14) were independent predictors of poor SQ. In the second stage, the effect of rhythm control on the SQ of the 54 patients with successful DCC was analyzed. PSQI scores improved significantly between baseline and the 6 months in sinus rhythm maintenance group (8.7 ± 4.1 vs 7.2 ± 3.8, P < 0.001, respectively). However, in the AF recurrence group, the change in global PSQI scores between baseline and the sixth month was not statistically significant (9.8 ± 4.5 vs 9.2 ± 4.2, P = 0.56, respectively).

Patients with AF have shorter sleep duration and poor SQ. Maintenance of sinus rhythm after DCC may have a favorable effect on the SQ of patients with AF. Nevertheless, AF is an independent predictor of poor SQ.

A systematic literature search was performed using MEDLINE, EMBASE, and the Cochrane Library to identify RCTs comparing RVNA pacing with RVA pacing with follow-up ≥2 months. Twenty RCTs involving 1,114 patients were included.

Compared with RVA pacing, RVNA (mainly right ventricular septum [RVS]) pacing exhibited not only excellent pacing threshold and R-wave amplitude but also higher impedance. RVNA pacing showed a significant increase in left ventricular ejection fraction (LVEF) at the end of follow-up (weighted mean difference = 3.58, 95% confidence interval = 1.80–5.35), and the effects were observed in the following subgroups: 6-month follow-up, ≤12-month follow-up, >12-month follow-up, baseline LVEF ≤45%, and baseline LVEF >45%. RVS and RVA pacing significantly differed in improving LVEF (weighted mean difference = 4.82, 95% confidence interval = 2.78–6.87). In addition, RVNA pacing resulted in a narrower QRS duration, a smaller left ventricular end-systolic volume, and a lower New York Heart Association functional class.

This meta-analysis found that RVNA (mainly RVS) pacing exhibited satisfactory long-term lead performance compared with RVA pacing and demonstrated beneficial effects in improving LVEF after the 6-month follow-up. Furthermore, it proved superior to RVA pacing in terms of interventricular synchrony and cardiac function.

A total of 98 patients, mean age 35 ± 18 years, with WPW were admitted for syncope. Note that 29 were aged between 9 and 19 years (mean 15 ± 3) (children and teenagers/group I), 45 between 20 and 49 years (mean 34 ± 8) (adults/group II), and 24 between 50 and 70 years (mean 60 ± 8) (elderly/group III). EPS consisted of atrial pacing and programmed atrial stimulation in control state and after isoproterenol.

Potentially malignant form (rapid conduction in accessory pathway >240 beats/min in control state or >300 beats/min after isoproterenol and atrial fibrillation [AF] induction) was more frequent in group I (34%) than in groups II (7%) (P < 0.002) and III (0%) (P < 0.001). Orthodromic atrioventricular reentrant tachycardia (AVRT) and AF were induced as frequently in groups I (59, 34%), II (47, 15.5%), and III (54, 17%). AVRT was induced in all but one patient with malignant form. EPS was as frequently negative in groups I (27.5%), II (44%), and III (37.5%). Natural follow-up (mean 8 ± 6 years) indicated a favorable prognosis, only related to AVRT induction. Induced AF was without significance.

Data in syncope and WPW syndrome depended on age: electrophysiological malignant form was frequent in children/teenagers, rare in adults, and absent in elderly. AVRT, the main cause of syncope, was as frequent in all ranges of age. AF's induction alone had no significance. Final prognosis was favorable.

To determine the benefit of CRT with or without a defibrillator in older elderly patients.

We retrospectively studied consecutive patients who received CRT at our institution from 2002 through 2008. New York Heart Association (NYHA) class and echocardiographic parameters were assessed before and after CRT. Thirty-day complications after device implant were collected. Survival data were obtained from the national death and location database. Data were compared between those 80 years and younger and those older than 80 years.

Of 728 patients identified, 90 (12.4%) were older than 80 years. After CRT, older and younger patients had similar improvements in NHYA class (P = 0.41), ejection fraction (P = 0.48), and mitral valve regurgitation (MR) severity (P = 0.42). In the older patients, defibrillator implantation was associated with comparable improvement in NYHA class, ejection fraction, and MR grade severity (P > 0.05), as in those without a defibrillator. Overall survival was worse in octogenarians than in the younger patients by Kaplan-Meier estimates (P = 0.001). Multivariate analysis showed similar survival between the younger and older subjects (hazard ratio, 1.23; 95% confidence interval, 0.83–1.84; P = 0.31). The observed complication rate in all study subjects was 12.2%, with no difference between the two age groups.

Octogenarian patients who received CRT with or without a defibrillator for advanced heart failure had similar clinical benefits as younger patients. CRT should not be withheld from octogenarians meeting current selection guidelines.

PS participants were matched on sex and age with individuals who received objective shocks only (OSO). Participants were interviewed and completed measures of posttraumatic stress disorder (PTSD Checklist—Civilian Version), depression and anxiety (Hospital Anxiety and Depression Scale), disease-specific distress (Cardiac Anxiety Questionnaire—CAQ), and social desirability (Socially Desirable Response Set—SDRS). Interviews were analyzed using interpretative phenomenological analysis (IPA).

Seventeen male patients participated (PS: n = 9; OSO: n = 8). Three themes emerged from IPA: (1) PS as a somatic experience, (2) the emotional impact of PSs, and (3) searching for meaning. Quantitative analyses showed that both groups exhibited elevated trauma and anxiety levels. Effect size differences (ESD) suggested a medium ESD on depression (P = 0.176, η_p² = 0.118) and PTSD (avoidance: P = 0.383, η_p² = 0.055, numbing: P = 0.311, η_p² = 0.068), and a large ESD on SDRS (P = 0.081, η_p² = 0.189), where PS participants, comparatively, exhibited elevated levels. A medium ESD was detected on CAQ-fear (P = 0.237, η_p² = 0.092) where OSO participants exhibited greater heart-focused worry.

The qualitative and quantitative findings of this mixed method study show convergence in terms of the emotional factors associated with the experience of PSs. PSs are often reported to be indistinguishable from objective shocks, evoking alarm, frustration, and confusion, forcing the individual to face the uncertainties of what to them is a novel and confusing experience.

Our TTM database was reviewed. Patients younger than 21 years of age enrolled for TTM between 1990 and 2010 were included. The abnormal TTM recordings (not including elective replacement indicator) were identified. Logistic regression was used for statistical analysis. Note that P < 0.05 was considered significant.

We identified 186 patients. There were 75 (40%) epicardial systems. The mean age at TTM enrollment was 6.8 ± 5.9 years (2 months–20.2 years). There were 41 (22%) patients with abnormal TTM findings. The abnormalities were found in 23/75 (31%) epicardial and 18/111 (16%) transvenous systems (odds ratio [OR]: 2.3, 95% confidence interval [CI]: 1.13–4.62, P = 0.02). When controlling for age and presence of heart disease the OR for abnormal transmission in epicardial systems compared with transvenous was 2.1 (95% CI: 1.03–4.43, P = 0.04). Patients with epicardial systems were more likely to have capture abnormalities on TTM than transvenous systems (OR: 6.1, 95% CI: 1.9–19.5, P = 0.002).

Pediatric patients with epicardial PM systems are more likely to have abnormal TTM test (particularly capture problems) than patients with transvenous systems regardless of age or presence of heart disease. Consequently, patients with epicardial PM systems should be followed closely with TTM.

All patients <21 years of age undergoing ablation of SVT at our institution from June 2011 to April 2012 were included. EAM was not utilized in any case. An ALARA protocol of low frame rates (2 or 3 fps), low fluoro dose/frame (10–18 nGy/frame), and other techniques aimed at reducing use of fluoroscopy were employed. Demographics, procedural, and radiation data were analyzed.

Forty-two patients underwent ablation and were studied. Median age was 14.1 years (range 4.8–21.1 years), weight was 51 kg (range 18.2–75 kg), and body surface area was 1.51 m² (range 0.72– 1.94 m²). Seventeen (41%) had Wolff-Parkinson-White syndrome, 14 (33%) atrioventricular nodal reentrant tachycardia, and 11 (26%) concealed pathways. Median procedural time was 114 minutes (57–246 minutes). Median dose area product (DAP) for posterioanterior and lateral fluoroscopy was 343.2 uGym² (range 38.2–3,172 uGym²); the median air Kerma product (K) was 45.4 mGy (range 6.7–567.5 mGy). DAP and K are lower than prior data from EAM and fluoroscopy techniques. The acute success rate was 95%; no procedural complications.

An ALARA protocol for ablation of SVT reduced radiation to below levels previously reported for combined EAM/fluoro approaches. Success rates were excellent with no complications and without the costs of EAM.

In this report, we report an undescribed atypical magnet response due to an internal cross-talk with atrial oversensing during a specific part of interrogation, simulating atrial fibrillation.

We describe our technique and analyze the results of direct LV endocardial pacing.

Fourteen patients with failed resynchronization via CS (April 2006–September 2011) were selected. Using a femoral approach, we performed transseptal puncture and LV mapping, then fixed the active lead where the longest electrical delay was observed; the generator was placed in the anterior thigh. For resynchronization, eight patients with a device previously implanted through the upper veins received a single-chamber generator that was set to the VVT mode to sense the subclavian pacing spike. Six patients received a complete femoral resynchronization system with either a defibrillator or pacemaker. Patients were followed for 6–54 months.

The LV lead was successfully implanted in all cases. Two patients experienced excessive bleeding and two died during follow-up. All except one improved at least one New York Heart Association class and experienced improved left ventricle ejection fraction. One patient with recurrent episodes of ventricular fibrillation was asymptomatic.

Direct LV endocardial pacing is safe and may be a less risky, more efficient alternative than surgical epicardial lead implantation for resynchronization via CS.

The Pediatric Electrophysiology Database of a single institution was retrospectively reviewed for patients with clinical sustained (≥30 seconds of symptoms) AVNRT documented by noninvasive means who underwent cryoablation for AVNRT to determine if intermediate-term success with cryoablation for AVNRT can be achieved without inducibility of sustained AVNRT during electrophysiology study (EPS).

There were no differences between patients with sustained (≥30 seconds of tachycardia) AVNRT (N = 67) and patients with nonsustained (ns, ≥3 beats and <30 seconds of tachycardia) AVNRT at EPS (N = 16). Acute success was achieved without PR prolongation in all patients. Although duration of follow-up was shorter for the sustained group than the nonsustained group (2.7 ± 1.6 years vs 3.8 ± 1.4 years, P = 0.008), recurrence rate was similar (6% vs 6.3%, P = 0.6). In patients with only nonsustained AVNRT at EPS, supportive findings for procedural effectiveness seen: (1) Dual atrioventricular node physiology (DAVNP) was eliminated in 14/14, (2) the fast pathway effective refractory period (FPERP) decreased after ablation in 10/11, (3) sustained slow pathway conduction was eliminated in 8/8 including both patients without discrete DAVNP prior to ablation, and (4) FPERP increased during lesion formation in 10/10.

Intermediate-term success can be achieved with cryoablation of ns AVNRT. Attention should be paid to supportive indicators of damage to slow pathway.

Between January 5, 1988, and March 5, 2008, 49 patients with functional C2-tetraplegia received an Atrostim PNS (Atrotech Ltd., Tampere, Finland) as treatment of their respiratory insufficiency; a follow-up of 35 of such patients was carried out exclusively in our institution for 6.3 (4.44) 0.04–15.75 years (mean [standard deviation (SD)] range). The device employed four-pole sequential nerve stimulation, which provided four threshold currents subsequently evaluated for each phrenic nerve. Stimulation data were prospectively recorded. The differences between threshold currents recorded 1 year after implantation and the last recorded values were 0.33–0.43 (0.44–0.63) 0–2.9 mA. After having excluded the data of eight patients with values >1 mA (= mean + SD), we registered the differences for the remaining patients of 0.15–0.24 (0.14–0.24) 0–0.95 mA, which is just twice the adjustment accuracy of the device. Out of the eight problem cases one had, and two were suspected to have, surgical trauma; all three nerves recovered. In two cases the values steadily increasing over years might have been caused by unspecific foreign body reaction. Two cases with values >1mA for different durations at different electrodes might be caused by biofilm, and one patient displaying steadily increasing values lived, unwilling to live, only 2 years after the implantation.

Thus, there was no permanent nerve injury and in 77% of the presented cases threshold currents remained stable.

Ninety-two patients scheduled for elective RFA completed repeated questionnaires comprising the Medical Outcomes Short Form 36, Hospital Anxiety and Depression Scale, and an in-house questionnaire designed to assess the burden of symptoms related to arrhythmia (arrhythmia-related burden score). Mean scores were generated and compared at time points while waiting, before and after the procedure. Regression analyses were carried out to identify predictors of increased psychological morbidity while waiting and immediately prior to the procedure. Health care costs during the waiting period as a consequence of arrhythmia were quantified.

Mean scores for parameters of psychological morbidity worsened during the period of waiting and improved after the procedure. Predictors of adverse effects within the cohort varied according to the time point assessed for each of the measures of psychological morbidity. A conservative estimate of the health care cost incurred while waiting exceeds £181 per patient.

Waiting for radiofrequency ablation appears to be associated with adverse psychological effects and health care costs. These results may support strategies to reduce waiting times and prioritize resource allocation.

Children aged between 0 and 18 years who received combination therapy with amiodarone and propranolol for persistent monotherapy resistance tachyarrhythmia between 2007 and 2011 were included in the study. Treatment efficacy and adverse effects were evaluated by review of clinical signs and symptoms, 12-lead electrocardiogram, 24-hour Holter monitorization, liver enzymes, thyroid function tests, chest x-ray, and ophthalmologic examination.

A total of 25 patients (15 male and 10 female) were enrolled in this study with a mean age of 17.9 months (0–132) and a mean weight of 8.65 kg (2.2–25). In 18 patients, treatment was started before their first age. Tachyarrhythmia persisted in two patients despite combination therapy, and treatment regimen was changed. Complete control of the arrhythmia was achieved within the first 2 months of combination treatment in 20 patients, whereas in the remaining three patients short attacks of tachycardia who responded to dose increases were controlled beyond 2 months of treatment and no recurrence were observed. Overall, success of amiodarone-propranolol combination treatment was 92%. Mild elevation in thyroid-stimulating hormone level was observed in one patient that required discontinuation of treatment.

Our results suggest that a combination of amiodarone and propranolol is an effective and safe option for the treatment of persistent arrhythmias in neonates and infants, and may serve as a bridge to ablation therapy in older children.

The concentration-dependent electrophysiological effects of Wenxin Keli were evaluated in the isolated rabbit left ventricular myocytes and wedge preparation. Wenxin Keli selectively inhibited late sodium current (I_Na) with an IC₅₀ of 3.8 ± 0.4 mg/mL, which was significantly lower than the IC₅₀ of 10.6 ± 0.9 mg/mL (n = 6, P < 0.05) for the fast I_Na. Wenxin Keli produced a small but statistically significant QT prolongation at 0.3 mg/mL, but shortened the QT and T_p–e interval at concentrations ≥1 mg/mL. Wenxin Keli increased QRS duration by 10.1% from 34.8 ± 1.0 ms to 38.3 ± 1.1 ms (n = 6, P < 0.01) at 3 mg/mL at a basic cycle length of 2,000 ms. However, its effect on the QRS duration exhibited weak use-dependency, that is, QRS remained less changed at increased pacing rates than other classic sodium channel blockers, such as flecainide, quinidine, and lidocaine. On the other hand, Wenxin Keli at 1–3 mg/mL markedly reduced dofetilide-induced QT and T_p–e prolongation by attenuation of its reverse use-dependence and abolished dofetilide-induced early afterdepolarization (EAD) in four of four left ventricular wedge preparations. It also suppressed digoxin-induced delayed afterdepolarization (DAD) and ventricular tachycardias without changing the positive staircase pattern in contractility at 1–3 mg/mL in a separate experimental series (four of four).

Wenxin Keli suppressed EADs, DADs, and triggered ventricular arrhythmias via selective inhibition of late I_Na.

We reviewed 155 OHTs (mean age 52 ± 11 years, 72% males) and used 1:1 age-, sex-, and date-of-surgery-matched two control groups from patients undergoing surgical maze or only coronary artery bypass grafting (CABG). Using conditional logistic regression we compared the odds of AF within 2 weeks following OHT versus controls. Postoperative AF occurred in 10/155 (6.5%) OHT patients. The conditional odds of postoperative AF were lower for OHT as compared to controls (vs maze: odds ratio [OR] 0.27 [95% confidence interval (CI) 0.13–0.57], vs CABG: OR 0.38 [0.17–0.81], P = 0.003; and on additional adjustment for left atrial enlargement, vs maze: OR 0.28 [0.13–0.60], vs CABG: OR 0.14 [0.04–0.47], P = 0.0009).

Risk of postoperative AF is significantly lower with OHT as in comparison to surgical maze. As both surgeries entail isolation of the pulmonary veins but only OHT causes disruption of autonomic innervation, this observation supports a mechanistic role of autonomic nervous system in AF. The benefit of targeting the cardiac autonomic system to treat AF needs further investigation.

A systematic review and meta-analysis was performed. Relative risks (RRs) and 95% confidence intervals (CIs) were pooled.

Six observational studies including 2,358 patients were included. Of those, four studies were prospective cohort studies, and two were retrospective studies. Elevated BMI increased the risk of AF recurrence compared to normal BMI by 31%, where the difference between the two arms was statistically significant (RR = 1.308, 95% CI: 1.036–1.651, P = 0.02). Compared to normal BMI group, the overweight group had a 27% increased risk of AF recurrence (RR = 1.270, 95% CI 0: 961–1.679, P = 0.093) and the obese group had a significantly increased risk of AF recurrence (RR = 1.378, 95% CI: 1.006–1.887, P = 0.045). When compared to the overweight group, the obese group has a 12% increased risk of AF recurrence (RR = 1.116, 95% CI: 0.866–1.438, P = 0.397).

Elevated BMI is associated significantly with AF recurrence in patients undergoing catheter ablation. There is a graded relationship between elevated BMI and increased risk of AF recurrence.

We retrospectively analyzed data regarding ablations using a novel bidirectional catheter in a tertiary cardiac center and compared these in 1:5 ratio with a control group of procedures matched for age, gender, operator, and ablation type.

A total of 50 cases and 250 controls of median age 60 (50–68) years were studied. Structural heart disease was equally prevalent in both groups (39%) while history of previous ablations was more common in the study arm (54% vs 30%, P = 0.001). Most of the ablation cases were for atrial fibrillation (46%), followed by atrial tachycardia (28%), supraventricular tachycardia (12%), and ventricular tachycardia (14%). Median procedure duration was 128 (52–147) minutes with the bidirectional, versus 143 (105–200) minutes with the conventional catheter (P = 0.232), and median fluoroscopy time was 17 (10–34) minutes versus 23 (12–39) minutes, respectively (P = 0.988). There was a trend toward a lower procedure duration for the atrial tachycardia ablations, 89 (52–147) minutes versus 130 (100–210) minutes, P = 0.064. The procedure was successfully completed in 96% of the bidirectional versus 84% of the control cases (P = 0.151). A negative correlation was observed between the relative fluoroscopy duration and the case number (r = –0.312, P = 0.028), reflecting the learning curve for the bidirectional catheter.

The introduction of the bidirectional catheter resulted in no prolongation of procedure parameters and similar success rates, while there was a trend toward a lower procedure duration for atrial tachycardia ablations.