Ivabradine for Uncontrolled Sinus Tachycardia in Thyrotoxic Cardiomyopathy - Case Report

Abstract

Background: Beta-blockers, mainly propranalol, are usually administered to control heart rate in patients with thyrotoxicosis, especially when congestive heart failure presents. However, when thyrotoxicosis is not controlled, heart rate may be difficult to control even with maximal doses of propranolol. This presentation alerts physicians to the possibility of using ivabradine, a selective inhibitor of the sinoatrial pacemaker, for the control of heart rate.

Case presentation: We present a 37-year-old woman with thyrotoxicosis and congestive heart failure whose heart rate was not controlled with a maximal dose of beta blockers during a thyroid storm. The addition of ivabradine, a selective inhibitor of the sinoatrial pacemaker, controlled her heart rate within 48 hours.

Conclusion: Ivabradine should be considered in patients with thyrotoxicosis, including those with heart failure, in whom beta blockers are insufficient to control heart rate.

Keywords: Thyrotoxicosis; congestive heart failure; heart rate; ivabradine; sinus tachycardia; thyrotoxic cardiomyopathy.