[Renal artery stenosis. Doppler color study before and after angioplasty]

Doppler flowmetry can be successfully employed to assess arterial patency after percutaneous transluminal angioplasty (PTA). The aim of this study was to assess color Doppler sensitivity in detecting renal artery stenosis prior to percutaneous angioplasty (PTRA) and vessel patency after it. Eleven patients (7 males and 4 females) affected with renal artery stenosis, unilateral in 9 cases and bilaterally in 2, underwent color-Doppler evaluation 1 day before and 7 days after PTRA. The operator was unaware of dilatation results. A total of 13 stenoses were treated. The qualitative and quantitative parameters we employed were: a) broadening of the spectrum, b) peak systolic frequency > 4000 Hz, c) stenosis index > 50%. Before PTRA, mean systolic peak at the stenosis was 7978 (range 4050-12500 Hz), while stenosis index was 71.9% (range 48-89%). After PTRA complete recovery was observed in 5 cases, no improvement in 1 and incomplete recovery in 7. Doppler results were in agreement with those of angiography in 6/13 while partial agreement only was seen in 7/13. Our results, although obtained in a small and highly selected group of patients, would seem to support the value of color-Doppler for the follow-up of patients after PTRA.