Comparison of therapy detection times between implantable cardioverter defibrillators with standard dual- and single-chamber pacing

Previous implantable cardioverter defibrillators (ICDs) required patients i n need of dual-chamber (DDD) pacing for improved hemodynamic status to unde rgo implantation of separate devices to treat bradycardia and/or ventricula r arrhythmias. An investigation was conducted to verify the performance of a new ICD that combines both therapies. Sixty-nine patients at 17 European and Canadian centers were implanted with VENTAK AV models 1810/1815, ICD's that includes DDD pacing and algorithms designed to differentiate between atrial and ventricular arrhythmias. 36 of the cohort were compared to 32 patients tested at six centers with an exte rnal test device (VENTAK MINI). In both cohorts detection times were calcul ated for ventricular fibrillation (VF) induced at implant. The mean detecti on times (DT) from the VENTAK AV device were compared to the DT from the VE NTAK MINI device. Patient characteristics of the VENTAK AV and the VENTAK MINI control groups were similar. Mean VF detection time (+/- SD) with the VENTAK AV device wa s 2.21 +/- 0.54 seconds, as compared with 1.87 +/- 0.62 seconds with the VE NTAK MINI (p < 0.01), indicating that the difference in means did not excee d one second. The VENTAK AV system function did not demonstrate interaction with the pace maker function, as indicated by the clinical significance with the detectio n times of the study device. The difference in detection times between coho rts did not statistically exceed one second. Appropriate detection of the n ew ICD was not compromised by the addition of the dual-chamber pacing thera py.