Intraoperative imaging techniques in infrainguinal arterial bypass grafting: Completion angiography versus vascular endoscopy

This prospective study was designed to establish whether vascular endoscopy would provide more information on the graft lumen than standard completion angiography during infrainguinal bypass surgery. Ninety-nine patients with 102 infragenicular bypass grafts who underwent both angiography and angioscopy intraoperatively were evaluated. In 99 of the 102 patients the indication was critical limb ischaemia. Of the 102 bypass grafts, 81 were autogenous vein. Distally, 24 grafts were anastomosed to the below-knee popliteal segment, 64 extended to the crural and 14 to the pedal arteries. On completion of the distal anastomosis, grafts were first evaluated by angiography and then by angioscopy. The images obtained with the two monitoring modalities were compared by the operating surgeon and re-explorations were performed immediately if necessary. Completion angiography and angioscopy produced images of good quality in 96 and 97 cases, respectively. In 12 cases completion angiography showed abnormalities. Of these, five were located below the distal anastomosis and were not accessible to angioscopic examination. Conduit defects were found in seven instances. In one of them angioscopy showed the angiogram to be false-positive. Of the 90 grafts with normal completion angiograms, seven were found to show significant pathology on angioscopy. Compared to angioscopy, the sensitivity and specificity of angiography to detect abnormalities within the graft was 46% and 98%, respectively. Our results suggest that vascular endoscopy is superior to angiography for disclosing conduit defects, but that it does not provide adequate information about the distal arterial anatomy.