Duplex-Doppler long-term follow-up of renal transplant artery stenosis: case controlled study

The aim of this retrospective clinical study was to assess a long-term course of renal transplant artery stenosis with duplex-Doppler ultrasound, and its influence upon serum creatinine, hemoglobin concentration and hypertension, as well as to investigate a possible association between stenosis and the number of acute rejections. Thirty-four renal transplant recipients, aged 43 +/- 13 years, with significant (>50%) renal transplant artery stenosis as seen on Doppler ultrasound were compared with 34 renal transplant recipients without stenosis (excluded by Doppler). Patients of both groups were matched by age, sex, time of transplantation, type of renal transplant, and number of previous transplantations. We analyzed peak systolic velocity (PSV) in the renal transplant artery, resistance index (RI) at the level of intra-renal arteries, serum creatinine, hemoglobin concentration, blood pressure, the number of antihypertensive medications, and the number of acute rejections on a yearly basis. In the stenosis group, PSV was 2.1 +/- 0.5 m/s at 1 year after transplantation (controls 1.1 +/- 0.4), 1.9 +/- 0.5 at 2 years (0.9 +/- 0.4), 1.9 +/- 0.5 at 3 years (0.9 +/- 0.4); RI was 62 +/- 10% at 1 year (controls 68 +/- 7), 65 +/- 9 at 2 years (67 +/- 7), 63 +/- 9 at 3 years (67 +/- 7); serum creatinine was 128 +/- 58 micromol/L at 1 year (controls 129 +/- 43), 119 +/- 47 at 2 years (121 +/- 33), 125 +/- 54 at 3 years (127 +/- 32). Long-term course of renal transplant artery stenosis (>50%), treated medically or interventionally, seems to be stable and non-progressive (during a 3-year follow up). Spontaneous regression of stenosis to non-significant level is possible. No difference in graft function, blood pressure or the number of acute rejections was observed comparing the stenotic and non-stenotic groups.