Taking precautions with ACE inhibitors

A theoretical risk exists in patients with unilateral renal artery stenosis

Angiotensin converting enzyme inhibitors have revolutionised the treatment of congestive heart failure,1 hypertension,2 and diabetic nephropathy.3 After myocardial infarction, treatment with angiotensin converting enzyme inhibitors decreases the incidence of life threatening left ventricular failure and improves survival.4 Yet, despite appearing to be a panacea for vascular diseases, angiotensin converting enzyme inhibitors may present a hazard for patients with unsuspected atherosclerotic renovascular disease,5 and the size of that risk may be growing.

Convention dictates that if the serum creatinine concentration is unchanged several days after starting an angiotensin converting enzyme inhibitor there is no haemodynamically important renal artery stenosis. But this scenario applies only in bilateral renovascular disease: in unilateral disease these drugs may cause ischaemic damage and loss of function …