Atrial overdrive pacing in patients with sleep apnea with implanted pacemaker

RATIONALE: Atrial overdrive pacing markedly improved sleep-disordered breathing in a recent study. OBJECTIVES: Using a single-blind, randomized, crossover design, we aimed to reproduce these findings and investigate the possible underlying mechanisms. METHODS: Twenty ambulatory patients with an implanted pacemaker or cardioverter defibrillator were studied by polysomnography on 3 consecutive nights in a randomized, single-blind, crossover study in which devices were programmed for nonpacing or for overdrive pacing at 7 or 15 beats/minute faster than the mean nocturnal heart rate. Ventilation and biomarkers (urinary norepinephrine excretion, amino-terminal portion of the precursor of brain natriuretic peptide, or NT-proBNP, were also evaluated. MEASUREMENTS AND MAIN RESULTS: Neither the primary endpoint apnea-hypopnea index, nor the apnea index, oxygen desaturation, ventilation, or biomarkers were affected by the nocturnal atrial overdrive pacing. A small, clinically insignificant, rate-dependent reduction in the hypopnea index was evoked by pacing (nonpacing, 13.4 +/- 1.4; pacing 7, 12.9 +/- 1.4; pacing 15, 10.9 +/- 1.0; p < 0.01, analysis of variance). CONCLUSIONS: The lack of effect on the apnea-hypopnea index means that atrial overdrive pacing is inappropriate for treating sleep-disordered breathing.