Implication of Ivabradine Therapy in Up-Titrating Beta-Blocker Dose in Patients with Systolic Dysfunction.

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.