الفهرس 
Dilated CardiomyopathyOnly 14 pages are availabe for public view
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Abstract
Enhanced heart rate, generally observed in patients with congestive heart failure (CHF) due to increased sympathetic nervous activity, attenuates the impairment in cardiac output or preserves cardiac output at the cost of impaired left ventricular (LV) filling, increased myocardial O2 consumption, and reduced coronary perfusion time. Thus, heart rate slowing should, in theory, be beneficial in CHF. Indeed, large-scale clinical trials conducted with β-blockers in CHF suggest such an essential role of heart rate slowing, since the effects of β-blockers on cardiac function and survival are correlated with the magnitude of the heart rate slowing.
The rationale for adding Ivabradine, a pure heart rate-lowering agent to a β-blocker is to further reduce the consequences of excessive sympathetic stimulation primarily at the myocardial level in those patients who, despite therapy with a β-blocker, still have a relatively high resting HR.
In this study, we aimed to prospectively assess the efficacy of If channel blocker (Ivabradine commercially available as “Procoralan”) as an add on therapy in patients with idiopathic dilated cardiomyopathy using echocardiography.
This study was designed as a prospective, randomized, placebo-controlled study that involved 30 patients admitted in Ain Shams University hospital with the diagnosis of idiopathic dilated cardiomyopathy in sinus rhythm with LVEF≤40% and were receiving the maximally tolerated dose of ACEI and carvidelol in addition to aldosterone antagonist and other medications as the clinical status dictated.
The patients were randomized into two groups, the Ivabradine group and the placebo group using a computer generated randomization table.
The patients were followed up for three months with emphasis on heart rate and blood pressure measurement, NYHA functional class, and echocardiographic parameters including LV dimensions and volumes, LVEF(by M-mode and 2D using Modified Simpson’s method), fractional shortening, mitral regurgitant area, left atrial diameter and pulmonary artery systolic pressure..
In this study, there was a clearly evident significant reduction in the resting heart rate by a mean of 24.3% in the Ivabradine group (p<0.01), without a significant change in blood pressure. There was a strongly positive correlation between the resting heart rate achieved in the whole study population and the NYHA functional class after 3 months of randomization.
In the Ivabradine group, there was a statistically significant reduction in the 3 month follow up left ventricular diameters and volumes, with no statistically significant changes in LVEF by 2D and M-mode, fractional shortening (FS%), mitral regurgitant area(MR area), pulmonary artery systolic pressure (PASP) and left atrial diameter (LAD).
Importantly, no significant side effects (that led to drug discontinuation) were noted in the Ivabradine group.
• from the results of the present study, we conclude that heart rate reduction in patients with idiopathic dilated cardiomyopathy is associated with a better NYHA functional class with regression of left ventricular dimensions and volumes. Also, Ivabradine can be used safely as an add on therapy in patients with idiopathic dilated cardiomyopathy and sinus rhythm. As a pilot study, larger randomized studies with longer periods of follow-up should be undertaken to investigate the long-term benefits of Ivabradine in patients with idiopathic dilated cardiomyopathy and sinus rhythm.