204 Results of the CASA study: the automatic atrial capture management

Abstract

The CASA study has included 297 patients in France implanted with an EnPulse® dual chamber pacemaker (Medtronic, Minneapolis, USA). Purpose of this study is to compare manual atrial threshold (MAT) and threshold assessed by the automatic atrial capture management function (ACM). Patients are 76 +/− 10 years old; indications were atrio-ventricular block (AVB) 70% and sinus dysfunction (SD) 30%; 31% had paroxystic atrial arrhythmias before implantation. Measurement of P wave, manual atrial threshold and atrial lead impedance have been performed at implantation, before discharge, 6 to 12 weeks after and at 6 months follow-up. At each follow-up automatic atrial thresholds are collected by interrogation of the device via telemetry and compared with the manual values by R coefficient correlation test. Follow-up (Nb) P Wave (mV) Impedance (Ohm) MAT (Volt) R coefficient ACM (Volt) Implant (297) 2.8 ± 1.6 614 ± 225 0.8 ± 0.5 Post-op (269) 2.3 ± 1.2 537 ± 153 0.7 ± 0.4 1 1 0.844 0.7 ± 0.4 1 6–12 Weeks (238) 2.3 ± 1.05 518 ± 146 0.6 ± 0.4 2 2 0.849 0.7 ± 0.4 2 6 months (186) 2.4 ± 1.2 498 ± 142 0.7 ± 0.4 3 3 0.891 0.7 ± 0.5 3 P wave amplitude and atrial lead impedance are stable during follow-up without significant difference. Concerning atrial thresholds, there is no difference between manual and automatic thresholds at each follow-up. R coefficients are very high showing an excellent correlation between the two methods. We have observed a very good correlation between atrial threshold assessed by automatic atrial capture management function and manual atrial threshold test.