Atherosclerotic renal artery stenosis : is it worth diagnosing?

Atherosclerotic renal artery stenosis (ARAS) is the commonest cause of secondary hypertension and is the cause of end stage renal failure in up to 20% of patients starting dialysis. Associated with it is a high morbidity and appalling mortality. The aetiology of ischaemic nephropathy is complex and is not simply related to renal artery narrowing. Captopril renography is sensitive and specific for diagnosing ARAS in patients with normal renal function. In those with renal impairment gadolinium-enhanced MRA or spiral CT angiography clearly define renal anatomy. Over 80% of ARAS is ostial. Studies of revascularisation with angioplasty show poor short and long term patency rates. Renal artery stenting leads to high initial technical success and long term patency. Recent randomised controlled trials in patients with renovascular hypertension demonstrate no clear benefit of adequate revascularisation over medical therapy. Renal artery stenting for renal protection in ARAS appears more encouraging and current randomised controlled trials are in progress to answer the question definitively.