OPTIMIZING TECHNICAL SUCCESS OF RENAL REVASCULARIZATION - THE IMPACT OF INTRAOPERATIVE COLOR-FLOW DUPLEX ULTRASONOGRAPHY

Purpose: Technical problems with renal revascularization can be diffic ult to detect, especially with end points of transaortic renal endarte rectomies or anastomosis of bypass grafts to small distal renal arteri es. If missed, such technical mishaps may not be recognized until afte r operation, when the chance for timely renal salvage has often been l ost. Methods: To evaluate the value of newer color-flow duplex imaging , we performed intraoperative ultrasonography on 35 patients undergoin g revascularization of 64 renal arteries, 29 patients undergoing trans aortic endarterectomy, and 6 undergoing bypass grafting. Most patients (24/35; 69%) underwent concomitant aortic reconstruction. Ninety-four percent had hypertension, whereas 66% had associated chronic renal in sufficiency. Results. Technical abnormalities prompting operative revi sion were identified during surgery in 10.9% of reconstructed main ren al arteries (7/64). These included two occlusions, three intimal defec ts, and one extrinsic tissue band after endarterectomy plus one graft anastomotic stenosis. Color-flow imaging revealed all of them. Technic al defects were also associated with higher peak-systolic flow velocit ies (mean 2.62 m/sec; range 2.00 to 3.50 m/sec) than normal-appearing arteries (mean 1.34 m/sec; range 0.40 to 2.50 m/sec) (p = 0.004). Eigh ty-six percent of the defects (6/7) were immediately correctable. One patient required nephrectomy. Postoperative angiograms revealed two as ymptomatic small branch-vessel occlusions (3%). Compared with preopera tive levels (p < 0.01), both hypertension and renal insufficiency impr oved initially. The clinical outcome of patients requiring intraoperat ive revision did not differ from that of patients undergoing normal in traoperative studies. Conclusion: Intraoperative color-flow duplex det ection and surgical correction of technical problems with renal revasc ularization have enhanced our technical success and been associated wi th long-term results comparable to those of patients undergoing normal intraoperative studies.