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Preservation of renal function by percutaneous transluminal angioplasty in ischaemic renal disease.

BACKGROUND
The purpose of this study was to evaluate the effects of percutaneous transluminal renal angioplasty (PTRA) on preservation of renal function in patients with bilateral renal artery stenoses or stenosis of the artery of one functioning kidney.


METHODS
A total of 227 PTRAs of 223 stenoses in 135 patients were performed from 1982 to 1993 in a single centre and retrospectively reviewed. The number of PTRAs per patient was 1.7, range 1-6. Angiographical follow-up was performed in 77%, 120+/-82 days after the first PTRA and 273+/-345 days after the last PTRA. Follow-up of serum creatinine and blood pressure was performed in 85% after 414+/-558 days. Long-term follow-up was performed for dialysis, surgical revascularization, renal transplantation and death, mean follow-up 8.8 years, range 5.5-14.8.


RESULTS
The immediate technical success was 90%, and another 5% were improved. The primary patency rate per patient was 43% and the secondary patency rate 64%. Improved renal function was achieved in 23% of the patients, stabilized in 56% and failed in 21%. Stabilized or improved function was higher when baseline serum creatinine was < or =250 micromol/l (85%) than >250 micromol/l (60%). Three of 99 (3%) patients with creatinine < or =250 micromol/l started dialysis during follow-up (41 days, 7.4 and 8 years), as did 13 of 36 (36%) patients with creatinine >250 micromol/l. Blood pressure and the number of antihypertensive drugs decreased in patients with creatinine < or =250 micromol/l, but was unchanged in those with creatinine >250 micromol/l. The 5-year survival rates were 84, 66 and 17% for patients with creatinine <125 micromol/l, 125-250 micromol/l and >250 micromol/l, respectively. Twelve patients (9%) experienced complications, including two deaths.


CONCLUSIONS
Our study shows that PTRA improved or preserved the renal function in most patients with normal to moderately impaired renal function. Close follow-up and possibly re-intervention are necessary to obtain satisfactory clinical and angiographical result.