Effects of ivabradine on left ventricular function in dogs with congestive heart failure

Ivabradine is an essential drug administered in current standard therapy for human heart failure and is expected to be beneficial to congestive heart failure dog. Ivabradine is a selective If Channel inhibitor. It reduces cardiac pacemaker activity and slows heart rate. There are a few reports of ivabradine in veterinary applications. The aim of this study was to investigate the effects of ivabradine on left ventricular function in dogs with congestive heart failure. Thirteen client-owned dogs with systolic and/or diastolic heart failure were included in this study. The dogs were assigned to two groups: (i) the active control group, given propranolol at 0.5 mg/kg, and (ii) the group treated with ivabradine at an initial dose of 0.5 mg/kg twice a day for 7 days, followed by a maintenance dose of 0.3 mg/kg twice a day. Types of arrhythmias were confirmed by lead II ECG, blood pressure, and echocardiography were measured before and 15 and 30 days after treatment of ivabradine. Results showed decrease in heart rate and improvement in score of quality of life. Ejection fraction and left ventricular size remained normal. These results indicate that the treatment with ivabradine can decrease heart rate and improve quality of life in dogs with congestive heart failure with no adverse effects on cardiac contractility.