Long Term Results of Inframalleolar Bypass for Critical Limb Ischaemia

Abstract

Introduction: Distal peripheral arterial disease (PAD) causing critical limb ischaemia (CLI) has become more common as a result of increasing incidence of diabetes. Endovascular treatment has challenged bypass surgery as first line treatment in crural and foot arteries, although long term results of these interventions are lacking. The aim of this study was to evaluate long term results of infra-malleolar bypasses. Methods: Three hundred and fifty two infra-malleolar bypasses for CLI at our institution between 2002–2013 were included in to this retrospective study. Risk factors were evaluated and patency, leg salvage, survival and amputation free survival (AFS) were assessed. All patients who were alive without amputation were invited to clinical control and patency of grafts was assessed using duplex ultrasound. Results: The median follow up time 29 months (range 1 –163 months). The median age of study population was 73 years and 67% of patients were male. The incidence of diabetes was 69%. In majority of cases (78%) the indication for bypass surgery was ulcer or gangrene and 18% of patients had rest pain. All except four bypasses were performed using vein graft. At 1, 5 and 10 years primary patency was 71.2%, 58.2% and 45.3%, assisted primary patency was 76.8%, 68.5% and 54.4%, and secondary patency was 83.2%, 78.1% and 71.9%, respectively. Popliteal artery as inflow artery (n = 194) was associated with superior primary (p = 0.013), assisted primary (p = 0.028) and secondary patency (p = 0.014) compared to bypasses originating from femoral artery (n = 158). The recipient artery did not affect patency, pedal bypasses (n = 281) had equal patency compared to plantar bypasses (n = 71) (p = 0.920). The leg salvage rate at 1, 5 and 10 years was 78.6%, 72.0% and 67.2%. Leg salvage rate was equal in patients with and without diabetes (p = 0.460). The respective survival and AFS rates at 1, 5 and 10 years were 70.3%, 37.4% and 15.9% and 58.4%, 29.8% and 12.8%. Conclusion: Bypass to infra-malleolar arteries is durable treatment option for distal PAD in patients with CLI. These bypasses to foot arteries have excellent long term patency and good limb salvage rate can be achieved both in non-diabetics and diabetics.