Abstract
INTRODUCTION: Heart failure with preserved ejection fraction (HFpEF) represents approximately 50% of all heart failure cases and lacks effective treatments. Chronotropic incompetence contributes to exercise intolerance in these patients. This study evaluated the safety and efficacy of blood pressure-adaptive atrial pacing (BPAP) vs standard bradycardia pacing (STD) in hypertensive patients with HFpEF. METHODS: In this prospective, double-blind, randomized, self-controlled crossover study, 16 patients (mean age: 62.7 ± 10.9 years; 6% female; left ventricular ejection fraction 55.3 ± 3.8%) with treated hypertension and implanted dual-chamber pacemakers underwent two 3-week treatment phases (BPAP and STD) in random order. The BPAP algorithm-modulated atrial pacing rate in response to home blood pressure readings. Endpoints included the Minnesota Living With Heart Failure (MLWHF) score, New York Heart Association (NYHA) class, 6-minute walk test (6MWT), and modified Bruce treadmill test. RESULTS: BPAP improved MLWHF score by an additional 15% from baseline (P = .0288), whereas STD showed a non-significant 3% worsening. Exercise time increased significantly during BPAP (+83.2 ± 55.6 s, P = .005) but not during STD (+70.8 ± 84.4 s, P = .095). The 6MWT distance rose by 35.8 ± 29.9 m during BPAP (P = .003) vs minimal change with STD (+8.2 ± 40.1 m, P = .6). NYHA class improved in 55.6% of BPAP patients vs 11% with STD (P = .0455). Mean heart rate was higher during BPAP (83.8 ± 8.3 bpm) than STD (72.9 ± 12.0 bpm, P < .0001), with no difference in systolic blood pressure (137.5 ± 14.9 vs 138.6 ± 14.0 mmHg, P = .68). No adverse events occurred. CONCLUSION: In hypertensive patients with HFpEF and implanted pacemakers, BPAP safely improved exercise capacity and functional status compared to standard pacing. The approach demonstrates feasibility of home-based blood pressure-modulated pacing for physiologic rate adaptation. (NCT06036186).