Contemporary Systematic review and Meta-analysis of Outcomes associated with femoropopliteal above-the-knee non-autologous surgical bypass

OBJECTIVE: While endovascular therapy is increasingly used for femoropopliteal disease, surgical bypass remains an alternative for long-segment or heavily calcified lesions. However, contemporary outcomes for non-autologous conduits are not well-established. This systematic review and meta-analysis provides a modern benchmark for outcomes associated with above-the-knee (ATK) femoropopliteal prosthetic bypass. METHODS: A systematic search was conducted, leveraging a previously published search strategy while adopting a broader patient population, and inclusive of relevant records published through January 2023. Included studies reported a minimum of one-year follow-up of primary or secondary patency, mortality, or limb salvage, for patients who underwent femoropopliteal ATK revascularization via non-autologous surgical bypass. Risk of bias and quality of evidence assessments were conducted for each study and outcome. A pooled meta-analysis was performed using a random-effects model for all outcomes at 6-, 12-, 24- and 36-months based on available reporting. Extensive subgroup analyses were conducted for 12-month outcomes, including stratification of records by type of prosthetic conduit, outcome definition, period of data collection, disease severity, underlying bias, and study design. RESULTS: The final sample included N=16 records reporting on a total of 2,083 patients and 2,118 limbs. The pooled 6-, 12-, 24-, and 36-month overall event rates [95% CI] were as follows: 0.88 [0.85, 0.90], 0.80 [0.77, 0.82], 0.69 [0.65, 0.72], and 0.61 [0.57, 0.65] for primary patency; 0.92 [0.88, 0.95], 0.86 [0.82, 0.89], 0.79 [0.71, 0.84], and 0.68 [0.56, 0.78] for secondary patency; and 0.07 [0.02, 0.14], 0.09 [0.06, 0.13], 0.13 [0.10, 0.17], and 0.24 [0.13, 0.40] for mortality, respectively. Based on data available, only 12- and 24-month pooled estimates were derived for limb salvage, with resulting event rates of 0.97 [0.91, 1.00] and 0.98 [0.66, 1.00]. Primary patency was generally more favorable for records adopting a Society for Vascular Surgery-oriented definition of primary patency, meaning freedom from flow-restoring or maintenance interventions. The 12-month pooled estimates for subgroup analyses stratified by type of prosthetic conduit were comparable for PTFE and Dacron across all outcomes. Additional details of subgroup analyses explored are discussed. CONCLUSIONS: The current analysis provides comprehensive perspective on contemporary outcomes of non-autologous ATK femoropopliteal surgical bypass. In the management of long femoral-popliteal lesions in patients lacking suitable greater saphenous vein conduit, the anticipated results of an endovascular approach must be compared to those included herein for prosthetic femoral-popliteal bypass. These data, with reporting of up to 36 months follow-up, should be weighed for treatment decision making. FUNDING: This work was supported by Endologix Inc., Irvine, CA, United States.