Many sophisticated techniques are employed in order to diagnose cardiovascular disease and assess long-term prognosis. It may be that the simple measurement of resting heart rate can provide useful prognostic information. Epidemiological studies show that a resting tachycardia is associated with increased risk of cardiovascular disease and sudden death. Elevated heart rate is also highly and independently predictive of 6-month and 1-year mortality following acute myocardial infarction. This article reviews some of these studies and supports the view that measurement of the heart rate at rest should be an integral and routine part of the clinical examination and that it should have a role in determining patient prognosis...