Heart rate (HR) is a major determinant of myocardial oxygen consumption and myocardial perfusion in patients with ischaemic heart disease. Large epidemiological studies have demonstrated that high resting HR is a strong predictor of total and cardiovascular mortality in the healthy population and in patients with hypertension, in patients with metabolic syndromes, in the elderly, and in patients with coronary artery disease (CAD). HR modulation with beta-blockers has shown favourable effects on post-myocardial infarction mortality in correlation with their HR-lowering actions. In this regard, because of their pharmacological action, inhibitors of the sinus pacemaker I f current, agents that exclusively reduce HR, may be of particular importance as antianginal agents, and have potential utility in reducing morbidity and mortality in cardiovascular disorders in patients with CAD and in patients with heart failure. Sinus tachyarrhythmias are a heterogeneous group of disorders that are often difficult to manage. A pure HR reduction may be a novel way of treatment for these patients.