[Inter-electrode distance and atrial sensing. Our experience with atrial-guided pacing (VDD) in the biennium...

We implanted 47 Phymos VDD pacemakers (53.7% for complete atrioventricular block-42.57% for symptomatic lower heart block) in the 1990-91 period. In this series of cases with EDE 830-830S leads by means Holter technique we evaluated the atrial trigger. A high percentage of atrial sensing (97.8%) was found with 11 cm leads. The right atrial motion study is realized to explain the atrial sensing with floating leads.