Clinical Experience and Procedural Outcomes Associated with the DF4 Implantable Cardioverter Defibrillator System: The SJ4 Postapproval Study
Address for reprints: Daniel J. Cantillon, M.D., Cardiac Electrophysiology and Pacing, Heart and Vascular Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Desk J2–2, Cleveland, OH 44195. Fax: 216-445-6149; e-mail: email@example.com
Current implantable cardioverter defibrillators (ICDs) employ two or three low- and high-voltage lead connectors, adding complexity and bulk, sometimes resulting in incorrect connections and adverse events. The SJ4 study evaluates the performance of a novel integrated single-lead DF4 connection system by characterizing lead measurements, handling characteristics, and outcomes.
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.