New perspectives on heart failure due to myocardial ischaemia

with a marked and progressive increase in incidence with age from 0·2 cases per 1000 population per annum aged 35‐44 years to 11·6 cases per 1000 population per annum aged over 85. The proportion of patients with heart failure due to coronary heart disease varies substantially between studies. Evidence for coronary heart disease can be based on the patient’s history without objective evidence of coronary artery disease or on a validated history of myocardial infarction. The latter could underestimate the role of coronary heart disease when used in retrospective studies. Electrocardiogram (ECG) findings, using the presence of Q waves or left bundle branch block will detect silent infarcts but will underestimate the presence of coronary artery disease. Q waves may not be due to infarction. Coronary angiography will identify those patients in whom coronary artery disease is present. However, to determine that coronary artery disease is the cause of myocardial dysfunction may require further evidence. Coronary artery disease is clearly implicated where a blocked vessel subtends a regional infarct, but in other cases where a modest coronary stenosis subtends an area of resting contractile dysfunction the causative nature of the association cannot be proven. Imaging involving echocardiography, magnetic resonance imaging or nuclear techniques may be needed in an attempt to demonstrate a causative and dynamic relationship between coronary artery disease, myocardial dysfunction and heart failure. The Framingham study, a prospective study using biennial history, examination and ECG recordings, found evidence of coronary artery disease (noninvasively) in 42% of men and 25% of women predating heart failure [7] . However, the proportion of heart failure cases due to coronary heart disease is greater in other, particularly more recent, studies using diVerent methodologies. A surveillance study in Eastern Finland, using non-invasive data, reported coronary artery disease as the aetiology in 61% of cases of heart failure