VDD pacemaker: An effective and reliable physiological pacing modality in elderly patients.

Background: In elderly patients, single chamber pacing may be considered. For sinus rhythm patients, VDD pacemaker (PM), by preserving atrial sensing, is a more physiological mode than VVI devices. This study aims to evaluate the long-term performance of VDD PM in elderly patients with atrioventricular block (AVB).

Methods: We conducted a retrospective, observational study of 200 elderly patients (≥75 years) with AVB and normal sinus rhythm who consecutively implanted VDD PM between 2016 and 2018. Baseline clinical characteristics were analyzed, complications related to pacemaker implantation were assessed and a 3-years follow-up (FUP) was made.

Results: Mean age was 84 ± 5 years. After 3-years FUP, 90.5% (n = 181) of the patients preserved their original VDD mode. Only 19 patients (9.5%) switched to VVIR mode, 5.5% (n = 11) due to P-wave undersensing and 4% (n = 8) due to permanent AF. Those patients had a less amplitude of sensed P wave at baseline [median value of 1.30 (IQR 0.99-2.0) versus 0.97 (IQR 0.38-1.68), p = 0.04]. One third of the patients died during the FUP, 89% (n = 58) from non-cardiovascular causes. All-cause, CV, and non-CV mortality did not relate with atrial sensing loss during FUP (p = 0.58, p = 0.38 and p = 0.80, respectively). However, atrial sensing loss during FUP was associated with de novo atrial fibrillation (12.7% vs. 31.6%, p = 0.038).

Conclusion: VDD pacing is a reliable pacing modality in elderly patients even in long-term. The majority of VDD-paced elderly patients maintained their original VDD mode program, with good atrial sensing.