Brain natriuretic peptide: a marker of cardiac dysfunction with ventricular or dual-chamber pacing.

BACKGROUND/OBJECTIVES: The inability of trials to exhibit the superiority in survival of atrioventricular compared to ventricular pacing can be partially explained by the apical stimulation of the right ventricle, which adversely affects both short- and long-term ventricular performance. We evaluated the impact of pacing mode (DDDR vs. VVIR) on the brain natriuretic peptide (BNP) level in patients with sick-sinus syndrome (SSS).

METHODS: Sixty-seven patients were treated with DDDR pacemaker implantation due to SSS. They were randomized during the first post-implant day either to DDDR or WIR pacing mode and were reevaluated after 30 days. Group A comprised 35 patients on DDDR pacing mode and group B 32 patients on WIR pacing mode. Peripheral blood samples were drawn for BNP measurement at the time of randomization and one month later.

RESULTS: BNP levels increased significantly in both groups at 30 days (group A: 85.6 +/- 29.5 pg/ml to 107.2 +/- 34.6 pg/ml, group B: 82.7 +/- 27.6 pg/ml to 253.1 +/- 60.2 pg/ml). On day 30, BNP levels in group B were significantly higher than in group A (P < 0.0001).

CONCLUSIONS: Pacing from the apex of the right ventricle provokes an increase in the BNP levels regardless of the pacing mode. BNP is probably a very early marker predicting the structural and/or functional heart changes after long-term pacing from the apex of the right ventricle.