Beta-blocker dose up-titration or addition of ivabradine in stable angina: more is not necessarily better : editorial to: 'efficacy of ivabradine in combination with beta-blocker versus uptitration of beta-blocker in patients with stable angina' by E. Amosova et al.

摘要

The main action of ivabradine is to reduce heart rate through selective I-current blockade [1]. The Icurrent is the major determinant of diastolic depolarization in the sinoatrial node and, and hence Icurrent dictates the intrinsic pacemaker rate during rest and exercise [2]. Reduction in heart rate is desirable in conditions such as coronary artery disease and congestive heart failure because it increases diastolic time and so improves coronary blood flow and left ventricular filling while reducing cardiac work and myocardial oxygen consumption [3]. Hence, it is not surprising that ivabradine has been demonstrated to improve anginal symptoms and exercise performance in patients with coronary artery disease [4].