Ivabradine in chronic diastolic heart failure

Abstract

Background: Ivabradine has proved effective in patients with systolic heart failure improving survival and hospitalization rate from heart failure deterioration. Its main action is to reduce heart rate, ameliorating diastolic filling of the ventricles and improving cardiac output. This mechanism could play an important role in patients with heart failure due to left ventricular diastolic dysfunction. Purpose: The aim of the present study is to evaluate prospectively the effect of ivabradine on diastolic function in addition to optimum guideline-based treatment, and its impact on exercise capacity and echocardiographic indexes of diastolic heart failure. Methods: We enrolled 30 patients with diastolic heart failure (mean age 55±11yrs), NYHA class II/III with mean heart rate ≥75bpm and optimal medical treatment. Ivabradine was prescribed to these patients initially at a dose of 5mg bid and gradually uptitrated to 7,5mg bid. Before the initiation of ivabradine and three months later the patients underwent clinical evaluation, cardiopulmonary test to evaluate exercise capacity (exercise duration ED, peak oxygen uptake V02max) and echocardiographic evaluation (assessment of E-wave deceleration time EDT, isovolumic relaxation time IVRT, tissue Doppler assessment at the mitral annulus E/Em). Results: After 3 months of follow up heart rate has decreased from 85±5 t0 68±3bpm and NYHA has improved from class III to class II. Exercise capacity ameliorated (ED from 6,1±1,9 vs 7.3±1,4, P<0.05, PeakVO2 ml/kg/min from 15,6±2,1 to 17,9±2,8 P<0.05). Echocardiographic indexes have also improved EDT from 257±12 ms to 240±12ms p<0.02, IVRT from 83±9ms to 75±13ms, p<0.05, E/Em from 12,2±2,2 to 10,5±1,6 p<0,05). Conclusion: Addition of ivabradine to optimum medical treatment seems to improve functional status, exercise capacity and echocardiocardiographic indexes of diastolic function in patients with diastolic heart failure.