Dr. Kumar is the recipient of a postgraduate research scholarship co-funded by the National Health and Medical Research Council and the National Heart Foundation of Australia (Scholarship ID 628996).
Catheter-Tissue Contact Force Determines Atrial Electrogram Characteristics Before and Lesion Efficacy After Antral Pulmonary Vein Isolation in Humans
Article first published online: 11 OCT 2013
© 2013 Wiley Periodicals, Inc.
Journal of Cardiovascular Electrophysiology
Volume 25, Issue 2, pages 122–129, February 2014
How to Cite
KUMAR, S., CHAN, M., LEE, J., WONG, M. C.G., YUDI, M., MORTON, J. B., SPENCE, S. J., HALLORAN, K., KISTLER, P. M. and KALMAN, J. M. (2014), Catheter-Tissue Contact Force Determines Atrial Electrogram Characteristics Before and Lesion Efficacy After Antral Pulmonary Vein Isolation in Humans. Journal of Cardiovascular Electrophysiology, 25: 122–129. doi: 10.1111/jce.12293
J.B. Morton reports research support from St. Jude Medical and Biotronik. J.M. Kalman reports participation on research grants supported by Medtronic, St. Jude Medical, and Biosense Webster, as well as research support from Biosense Webster. Other authors: No disclosures.
- Issue published online: 12 FEB 2014
- Article first published online: 11 OCT 2013
- Accepted manuscript online: 19 SEP 2013 07:30AM EST
- Manuscript Accepted: 29 AUG 2013
- Manuscript Revised: 25 AUG 2013
- Manuscript Received: 19 JUN 2013
- National Health and Medical Research Council
- National Heart Foundation of Australia. Grant Number: 628996
- atrial electrogram;
- atrial fibrillation;
- average contact force;
- catheter ablation;
- catheter-tissue contact force;
- force–time integral;
- lesion efficacy;
- maximum power;
- tip temperature
Catheter-Tissue Contact Force Determines Atrial Electrogram Characteristics
Electrogram (EGM) characteristics are used to infer catheter-tissue contact. We examined if (a) atrial EGM characteristics predicted CF and (b) compared the value of CF versus other surrogates for predicting lesion efficacy.
Methods and Results
Twelve paroxysmal AF patients underwent pulmonary vein isolation using radiofrequency (RF) ablation facilitated by a novel CF-sensing catheter. Operators were blinded to CF. EGM amplitude, width, and morphology were measured pre- and post-RF. At each RF site, average CF, force–time integral (FTI), impedance fall, time to impedance plateau, maximum power, catheter tip temperature, and total energy delivered were recorded. An effective lesion was defined based on previously validated EGM criteria for transmural lesions. There was a moderate correlation between CF and EGM amplitude (r = 0.19) and EGM width (r = −0.22). Pre-RF, EGM amplitude, and width had modest to poor discriminative capacity for identifying preablation CF (e.g., EGM amplitude identified CF>20 g with sensitivity and specificity of 67% and 60%, respectively). Preablation CF, FTI, and total energy delivered during RF were the only independent predictors of effective lesion formation. Neither pre-RF EGM amplitude/width nor power, temperature, and impedance changes during RF predicted effective lesion formation. An average CF >16 g or FTI >404 g*s had excellent sensitivity and specificity (>80%) for identifying an effective lesion.
EGM characteristics do not reliably predict either CF before the onset of RF, nor do they predict the likelihood of an effective lesion. CF parameters were superior to power, temperature, and impedance changes during RF in predicting lesion efficacy.