Antibradycardia pacing in patients with congenital heart disease: Experience with automatic threshold determination and output regulation (Autocapture™)

Aims. The purpose of this study was to reevaluate whether St Jude Medical's Autocapture™ algorithm (AC) with beat-to-beat capture confirmation, automatic pacing threshold determination and output adjustment can be applied to paced patients with congenital heart disease (CHD). Methods and results. 30 patients with CHD received a transvenous (group A: n=22) or epicardial (group B: n=8) single (n=7) or dual chamber (n=23) AC pacemaker for antibradycardia pacing. As a safe AC function is ensured only if a sufficient evoked response (ER) and a low lead polarization amplitude (LPA) are present, these parameters were reevaluated from 112 follow-up studies with respect to AC-function. In all but one transvenous system AC correctly functioned. AC was recommended in 5/8 patients with epicardial leads but correct AC function was preserved in only 3 patients. Conclusion. These data suggest that the application of the AC algorithm is safe in patients with CHD when transvenous leads are used. Whether appropriate AC function is possible with epicardial leads needs individual verification.