How to compare results from open with endovascular procedures?

Background According to the guidelines, bypass surgery is still the golden standard treatment in patients with femoropopliteal TASC C and D lesions and life-style limiting claudication or critical limb ischemia. Over the past few decades, endovascular therapy has made great advancements. However, the success rates of surgical and endovascular procedures cannot be directly compared. According to the surgical term "patency," vessel patency can be maintained even in case of a high grade stenosis, whereas according to the endovascular primary patency definition, being binary restenosis, patency is lost from the moment there is a re-narrowing at any location within the treated segment. Methods One hundred consecutive patients with a previously implanted femoropopliteal bypass which was primary patent according to the surgical definition were included in this study. Once enrolled, duplex ultrasonography was performed, measuring the Peak Systolic Velocity Ratio for proximal and distal anastomosis. Results Out of the 100 bypasses that were considered patent according to the surgical definition, Peak Velocity Ratio of ≥2.4 were detected in 11 patients. Conclusions Based on these findings a 78% primary patency according to the open vascular criteria turned into ~70% primary patency using the stricter endovascular criteria. In the light of these findings, one might conclude that modern endovascular treatment of long TASC C and D femoropopliteal lesions yielded similar results in terms of primary patency as above-the-knee bypasses.