The effect of percutaneous dilatation of renal arterial stenosis on captopril renography in hypertension.

Background: The clinical effects of percutaneous transluminal renal artery angioplasty (PTRA) in patients with renal vascular stenosis and hypertension is controversial.

Methods: We consecutively recruited all 23 patients referred for evaluation of renovascular hypertension that eventually underwent unilateral PTRA, to be investigated with captopril MAG3 renography (CR), both before and after the endovascular procedure. Data were evaluated on an intention-to-treat basis.

Results: We found that the relative MAG3 clearance of the stenotic kidney increased (from 29.9+/-14% to 35.1+/-14%, p=0.01) and that the creatinine levels fell following the intervention (from 110+/-19 to 99+/-17 micromol/l, p=0.0003). Blood pressure levels were also lowered (from 173+/-32/93+/-17 to 158+/-31/86+/-15 mmHg, p<0.006) while the mean number of anti-hypertensive drugs was unchanged following PTRA (2.9+/-1.4 before and 2.8+/-1.3 drugs after the intervention, respectively, p=0.6).

Conclusion: This prospective trial showed statistically significant improvements of individual kidney function as measured by CR and blood pressure in subjects with suspected renovascular hypertension treated with PTRA. Although the endovascular procedure was found to be safe, the magnitude of the absolute improvements was rather modest.