Ivabradine is a specific inhibitor of the If current of pacemaker cells in the sinoatrial node at concentrations that do not inhibit other cardiac currents.900 This action results in heart rate reduction, prolonging diastole and thereby improving myocardial oxygen balance. Ivabra- dine has no effect on BP, myocardial contractility, or intra- cardiac conduction parameters.901 903 Ivabradine improves exercise capacity and reduces anginal frequency in compar- ison to atenolol among patients with chronic stable an- gina.904,905 In 5479 patients with IHD and LV systolic dysfunction, however, ivabradine added to standard treatment had no effect, when compared with placebo, on the composite endpoint of cardiovascular death, admission to the hospital for AMI, and admission to the hospital for new-onset or worsening heart failure.906 The most common adverse event, reported in 14.5% of patients, is phosphenes, described as a transient enhanced brightness in a limited area of the visual field that typically occurs within the first 2 months of treatment. Most of these luminous visual-field disturbances (77%) resolve without discontinuing treatment. The drug is approved in Europe (not currently available in the United States) for the symptomatic treatment of chronic stable angina in patients with normal sinus rhythm with a contrain- dication or intolerance to beta blockers. 4.4.3.1.5.3. Trimetazidine. Trimetazidine seems to improve cellular tolerance to ischemia by inhibiting fatty acid metab- olism and secondarily by stimulating glucose metabolism, although the exact anti-ischemic mechanisms are un- known.907 In patients with chronic stable angina, this agent increases coronary flow reserve, delaying the onset of ische- mia associated with exercise and reducing the number of weekly angina episodes and weekly nitroglycerin consump- tion.908,909 The anti-ischemic effects are not associated with changes in heart rate or systolic BP. Few data exist on the effect of trimetazidine on cardiovascular endpoints, mortality, or quality of life. 