Assessment of renal artery stenosis with captopril renography followed by its treatment with angioplasty

ABSTRACT

To review the important pathophysiological changes in renal haemodynamics and in the rennin-angiotensin-aldosterone axis in response to significant renal artery stenosis and the effect of an angiotensin-converting enzyme inhibitor [captopril] on the function of the affected kidney. Hypertension due to renal artery stenosis is the most common of the curable forms of hypertension. Its early identification can best be accomplished by angiography which is invasive and inadvisable as a routine test. Captopril renography is accepted as the least invasive screening test available. Our experience with captopril renography as a screening test for renal artery stenosis as an aid to selecting patients for angiography and angioplasty is described. Twenty-nine hypertensive patients presenting with a suspicion of renal artery stenosis were studied with 99mTc-diethylenetriaminepentaacetic acid renography both before and after captopril administration. The test has been found to have a good sensitivity [100%] and a good specificity [89%]. Our results confirm the value of the test in selecting patients for angiography