Heart failure is predominantly a disease of older patients, and varies in its severity and presentation. Advances in the understanding of both the pathophysiology and approaches to treatment for patients with heart failure have resulted in marked improvements in prognosis over the past 20 years. In younger patients, heart failure is often a consequence of myocardial infarction, with resultant left ventricular remodelling and dilatation, while it is more likely to be due to hypertension, valvular heart disease and atrial fibrillation in older patients. Other heart-failure aetiologies include the cardiomyopathies and reno-vascular disease, and additional non-cardiac disease such as anaemia can result in a symptomatic deterioration.