Prospective comparison of intraoperative angiography with duplex scanning in evaluating lower-extremity bypass grafts in a community hospital.

The gold standard for intraoperative evaluation of lower-extremity bypass grafts has been angiography. Limitations of this technique include inability to measure flow dynamics, violation of graft integrity, cost, and length of assessment time. The goal of this study was to evaluate duplex scanning as an alternative modality for intraoperative graft assessment. Our study group comprised of 19 consecutive patients undergoing infrainguinal bypass procedures at our institution between March 1999 and March 2000. Intraoperative angiography was compared with duplex scanning by evaluating parameters of assessment time, graft flow velocities, serum creatinine levels, and 30-day graft patency rates. Mean study times were the following: cut-film angiography, 22 +/- 1.8 minutes; real-time fluoroscopy, 17 +/- 2.5 minutes; and duplex imaging, 10.4 +/- 1.1 minutes. As noted duplex imaging times as compared with radiographic modalities were significantly shorter (P < 0.05). There was a substantial cost difference between angiography ($650) and duplex scanning ($350). A 100 per cent correlation of study findings was noted between angiography and duplex scanning. No significant change in pre- versus postoperative creatinine levels was found. We conclude that duplex scanning is an effective modality and provides reliable intraoperative vascular graft assessment data in a community hospital setting. Advantages include a shorter study time, lower cost, flow dynamic data acquisition, and avoidance of mechanical graft trauma.