Autocapture compatibility in patients with the MembraneEX lead and Affinity pulse generators.

The first Autocapture generation worked well with all recommended leads. The newer Autocapture generation provides a more sensitive resolution for evoked response testing and its implementation in a dual-chamber device. The purpose of the study was to evaluate the performance of the Affinity SR/DR pacemaker with the new Autocapture algorithm in combination with the small surface area pacing lead MembraneEX in 129 patients. Autocapture ventricular threshold, sensing threshold, lead impedance, evoked response (ER) and polarization signals were determined at implantation and discharge, as well as after 1 and 3 months. Autocapture recommendation rate was based on the ER sensitivity test. The median pacing threshold was 0.38, 0.50, 0.75, 0.75 V at implant, discharge, 1 and 3 months post-implant, respectively. The respective data for median lead impedance were 744, 605, 649 and 691 ohms; median sensing threshold was 12.5 mV at all visits. The median ER amplitude was 9.0, 10.1, 9.9 and 10.1 mV and the median polarization signal 0.39 mV at all visits. The frequency of recommended Autocapture activation was 98.3%, 99.2%, 98.3% and 96.2% of all patients at implant, at discharge, 1 and 3 months post-implant respectively. In conclusion, the studied pulse generator enabled, in combination with this pacing lead, in >95% of all patients activation of Autocapture.