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.