Spontaneous regression of initially elevated peak systolic velocity in renal transplant artery

There is limited knowledge about the incidence, clinical implication and spontaneous course of transplant renal artery stenosis detected early after renal transplantation. We performed Doppler ultrasound examination of the transplant artery(s) 2 months after transplantation in 98 consecutive patients and peak systolic velocity (PSV) was measured. All patients with an elevated PSV ≥1.8 m/s were reexamined 20 months later and clinical data were followed for 3 years. At the initial examination 2 months after transplantation 15 recipients had a PSV ≥1.8 m/s, mean value for PSV 2.5 (1.8-3.6) m/s, whereas 83 recipients had a normal PSV of 1.3 (0.7-1.7) m/s (P<0.01). At baseline there were no statistical significant differences in clinical parameters between the high PSV versus normal PSV recipients. Twenty (15-28) months after transplantation 14 patients with initial elevated PSV were re-examined. There was an overall mean reduction in PSV of 0.5 (-0.7 to 1.2) m/s from 2.4 (1.8-3.4) m/s to 1.9 (1.2-3.1) m/s (P=0.02). Detection of a high PSV early after transplantation did not affect graft function or blood pressure 3 years after engraftment. We conclude that a high PSV, at 2 months after engraftment, seems to be more of an 'incidental finding' that should be re-challenged and carefully interpreted.