Prophylactic use of the silver-acetate-coated graft in arterial occlusive disease: a retrospective, comparative study

OBJECTIVE: Silver-coated vascular polyester prostheses were developed not only for the treatment of prosthetic graft infections, but also for use as prophylaxes. Although some studies describe the use of these prostheses in cases of infection, there are few data on their prophylactic use. This study compares the performance of the InterGard Silver polyester graft (Intervascular, Datascope, Inc, La Ciotat, France) with that of standard prostheses in routine use.

METHODS: This retrospective study included all patients who received alloplastic bypass for treatment of arterial occlusive disease at the University Hospital in Würzburg from January 1996 to December 2006. The courses of disease were analyzed by examining the medical records. Follow-up research documented long-term results.

RESULTS: The cases of 913 patients were analyzed (430 silver grafts, 483 standard grafts). Indications for the operations were claudication (silver: 136, nonsilver: 212), rest pain (49/65), tissue loss (135/148), and acute occlusion (110/58). Prosthetic implantation was performed in the aorto-iliaco-femoral position (silver: 93, nonsilver: 146), in the femorodistal position (309/304), and as multilevel reconstruction (28/33). With regard to perioperative complications, the two groups did not differ significantly. There were no silver release-related complications, such as colored exudation or wound staining. Mean follow-up time was 56.7 +/- 1.6 (SEM) months. When corrected for redo procedures, stage of disease, and type of reconstruction, both materials performed equally well: 5-year patency for claudication: silver 91%, nonsilver 95%, femorodistal 47%/41%; 5-year patency for critical ischemia: aortofemoral 88%/93%, femorodistal 31%/35%; 5-year limb salvage (critical ischemia): aortofemoral: 78%/79%; femorodistal: 59%/67%. Graft infections (Szilagyi grade III) were detected in 59 patients (6.4%; silver: n = 32, 7.4% vs control: n = 27, 5.5%; P = .28) after an average of 321 +/- 96 days. One infection occurred out of 93 aortofemoral operations with the silver prosthesis (1.1%) compared to 4.1% (6/146) in the control group (P = .17). For patients with femorodistal grafts, silver exhibited an infection rate of 9.4% compared to 5.9% (P = .11). In the multiple regression analysis, two factors influenced the rate of a graft infection significantly: wound healing impairment and revision after bypass implantation. Silver did not prevent a subsequent bypass infection in these cases (silver: 18.1% vs 12.5%, P = .27).

CONCLUSION: The silver-coated prosthesis did not differ from standard materials. Silver had no significant effect on the risk of graft infection. Our study showed good results with the silver prosthesis in the aorto-iliaco-femoral position, but in cases of femorodistal grafting, a reduction of prosthetic infections was not achieved. The silver grafts did not prevent subsequent infections in cases of tissue loss or postoperative local complications.