Int Heart J. 2021 Nov 6. doi: 10.1536/ihj.21-387. Online ahead of print.
Ivabradine, which reduces heart rate (HR) without affecting sympathetic nerve activity, improves mortality and morbidity in patients with systolic dysfunction. However, its impact on up-titrating a concomitant beta-blocker dose in such a cohort, via increasing cardiac output and blood pressure and improving tolerability to beta-blockers, remains unknown. In this single-center, prospective, randomized control trial, patients with systolic dysfunction, defined as left ventricular ejection fraction < 50%, sinus rhythm, heart rate > 75 bpm, systolic blood pressure between 90 and 110 mmHg, and New York Heart Association functional class III or IV, who are refractory to up-titration of a beta-blocker due to symptomatic hypotension, dizziness, or worsening heart failure, were assigned to the 20 ivabradine arm or the 20 conventional therapy arm and followed-up for 6 months. The primary outcome is the daily dose of beta-blocker at 6-months follow-up. The secondary outcomes are echocardiographic parameters including overlap between E-wave and A-wave in transmitral diastolic filling flow, plasma B-type natriuretic peptide level, 6-minute walk distance, and heart failure readmission rate. By conducting this study, we hope to demonstrate the clinical benefit of ivabradine therapy in up-titrating beta-blockers and improving clinical outcomes in patients with systolic dysfunction.