Optimal conduit choice in the absence of single-segment great saphenous vein for below-knee popliteal bypass

Abstract

Single-segment great saphenous vein (SSGSV) remains the conduit of choice for femoral to below-knee popliteal (F-BK) surgical revascularization. The purpose of this study was to determine the optimal conduit in patients with inadequate SSGSV. This was a retrospective review of a prospectively maintained vascular registry. Patients underwent F-BK bypass with alternative vein (AV; arm vein, spliced GSV, or composite vein) or prosthetic conduit (PC). From January 1995 to June 2010, 83 patients had unusable SSGSV for F-BK popliteal reconstruction. Thirty-three patients had an AV conduit and 50 had PC. The AV group was a lower median age than the PC group (69 vs 75 years). The two groups were otherwise similar in comorbid conditions of diabetes mellitus (57.6% vs 58.0%; P > .99), smoking (15.2% vs 32.0%; P = .12), and hemodialysis (3% vs 12%; P = .23). The groups were similar in baseline characteristics such as limb salvage as indication (93.9% vs 86.0%; P = .31), mean runoff score (5.2 vs 4.6; P = .39), and prior ipsilateral bypass attempts (18.2% vs 18.0%; P > .99). The AV and PC groups were also similar in 30-day mortality (6.1% vs 4.0%; P > .99) and wound infection rates (6.1% vs 6.0%; P > .99). PC patients were more likely to be discharged on Coumadin (Bristol-Myers Squibb, Princeton, NJ) than AV patients (62.0% vs 27.3%; P = .002). Seventeen of the 50 PC patients (34%) had a distal anastomotic vein cuff. A log-rank test comparison of 5-year outcomes for the AV and PC groups found no significant difference in primary patency (55.3% ± 9.9% vs 51.9% ± 10.8%; P = .82), assisted primary patency (68.8% ± 9.6% vs 54.0% ± 11.0%; P = .45), secondary patency (68.4% ± 9.6% vs 63.7% ± 10.4% for PC; P = .82), or limb salvage rates (96.2% ± 3.8% vs 81.1% ± 8.1%; P = .19). Multivariable analysis demonstrated no association between conduit type and loss of patency or limb. The factors most predictive of primary patency loss were limb salvage as the indication for surgery (hazard ratio [HR], 4.23; 95% confidence interval [CI], 1.65-10.9; P = .003) and current hemodialysis (HR, 3.51; 95% CI, 1.08-11.4; P = .037). The most predictive factor of limb loss was current hemodialysis (HR, 7.02; 95% CI, 1.13-43.4; P = .036). For patients with inadequate SSGSV, PCs, with varying degrees of medical and surgical adjuncts, appear comparable to AV sources in graft patency for below-knee popliteal bypass targets. This observation is tempered by the small cohort sample size of this single-institutional analysis. Critical limb ischemia as the operative indication and current hemodialysis predict impaired patency, and hemodialysis is associated with limb loss.