Low "gradient", low flow aortic stenosis.

Correspondence to: Dr John Chambers, Cardiothoracic Centre, St Thomas Hospital, London SE1 7EH, UK; jboydchambers@ aol.com _________________________ A ortic stenosis is thought to have a long, asymptomatic latent phase during which the risk of sudden death is low. In fact symptoms can be revealed by treadmill exercise in a large proportion of apparently asymptomatic patients. Patients may limit exercise to avoid symptoms or may fail to recognise the presence of exertional breathlessness or ascribe it to old age or some other condition. Such patients may then present in heart failure with relatively advanced disease when the left ventricle decompensates. Even in the presence of overt symptoms, physicians may fail to make the diagnosis often in the mistaken belief that severe aortic stenosis cannot coexist with systemic hypertension. Sometimes heart failure is precipitated in truly asymptomatic aortic stenosis by myocardial infarction, sepsis or another stress like non-cardiac surgery. For these reasons, the initial presentation for about 5% of patients having surgery is with heart failure rather than exertional chest pain or breathlessness. The four year survival of patients with a low ejection fraction and mean transaortic pressure difference , 30 mm Hg is only 35% compared with a survival of 60% if the mean pressure difference is . 30 mm Hg. Management decisions centre on confirming the grade of aortic stenosis and determining whether the left ventricle is likely to recover after surgery.