Autologous saphenous vein and heparin-bonded expanded polytetrafluoroethylene as graft materials for below-the-knee femoro-popliteal bypass in patients with critical limb ischemia: A propensity score-matched analysis.

OBJECTIVE: To compare the outcomes of heparin bonded expanded polytetrafluoroethylene (HePTFE) and autologous saphenous vein (ASV) in patients undergoing below-knee (BK) femoro-popliteal bypass for critical limb ischemia (CLI). DESIGN: Retrospective single-centre matched case-control study. METHODS: From 2003 to 2019, 275 consecutive BK bypasses for CLI were performed, 109 with the ASV and 166 with a HePTFE graft. All the baseline characteristics that were reliably measured and were potentially relevant in the decision-making process were included as confounders in a logistic regression model and the factors that were significantly different between the two groups then used to perform a propensity matching analysis. Propensity score-based matching was performed in a 1:1 ratio to compare outcomes. Arterial hypertension, hyperlipemia, the need for tibial anastomosis at the distal level and the run-off status were the covariates included in the matching. Follow-up outcomes were estimated by Kaplan-Meier methods and compared with log rank test. RESULTS: After propensity matching, 101 HePTFE bypasses were matched with 101 ASV bypasses. The median duration of follow-up was 37 months (range 1-192). The 5-year survival rate was 67.5% (standard error (SE) 0.05) in the HePTFe group and 64.5% (SE 0.06) in the ASV group (p = 0.8, log rank 0.04). Primary patency rates were 38% (SE 0.06) in the HePTFE group and 41% (SE 0.06) in the ASV group (p = 0.7, log rank 0.3). Also assisted primary patency and secondary patency rates did not differ in the two groups. Amputation-free survival was 53% (SE 0.05) in the HePTFE group and 58% (SE 0.06) in the ASF group (p = 0.6, log rank 0.2). CONCLUSIONS: HePTFE provided 5-year similar results to those obtained with use of the ASV in equivalent patients with CLI undergoing below-knee or tibial bypass.

Prevalence and risk factors for heparin-bonded expanded polytetrafluoroethylene vascular graft infection after infrainguinal femoropopliteal bypasses.

BACKGROUND: To analyze the prevalence and predictors of prosthetic vascular graft infection (PVGI) in a multicenter registry. METHODS: This registry-based, multicenter study retrospectively evaluated PVGI that developed after infrainguinal revascularization performed with a heparin-bonded expanded polytetrafluoroethylene graft that was used in 1400 interventions between 2002 and 2016. A prosthetic graft with infection was defined as direct involvement of the graft with positive bacterial cultures of graft or perigraft material, intraoperative gross purulence or failure of graft incorporation, or exposed graft in an infected wound. RESULTS: Critical limb ischemia (CLI) was the main indication for bypass (n = 915 [65%]). The median duration of follow-up was 29 months (range, 1-168 months; interquartile range, 12-60 months). A total of 33 heparin-bonded expanded polytetrafluoroethylene grafts (2.3%) became infected; the median time to occurrence was 5 months (range, 1-54 months; interquartile range; 2.00-13.25 months). Freedom from PVGI at 1 year was 98% (standard error, 0.4; 95% confidence interval [CI], 97.2-98.9), and 97% (standard error, 0.6; 95% CI, 95.6-98.0) at 5 years. The multivariate model identified CLI (P = .042; hazard ratio, 0.39; 95% CI, 0.164-0.969) to be independently associated with PVGI. In-hospital mortality of PVGI treatment was 12% (n = 4/33). Freedom from major amputation was significantly different between patients with PVGI and those who did not experience this complication (at 1 year, 67.0% vs 88.5%; Log-rank χ2 = 22.5; P = .001). CONCLUSIONS: In our "real-world" multicenter experience the prevalence of PVGI after infrainguinal femoropopliteal bypasses was relatively low at 2.3%, but still associated with significant mortality and limb loss. CLI was the only significant predictor of PVGI. This conclusion is reasonable; however, more comprehensive data are required to confirm these findings, because the presence of ischemic ulcers or gangrene was not predictive of PVGI.