Contemporary outcomes of endovascular interventions for acute limb ischemia

Abstract

Thrombolysis as a treatment for acute limb ischemia (ALI) has become a first-line therapy based on studies published over 2 decades ago. The purpose of this study was to assess outcomes of patients treated for ALI using contemporary thrombolytic agents and endovascular techniques. Consecutive patients with ALI of the lower extremities treated between 2005 and 2011 were identified, and their records were retrospectively reviewed. All patients were treated with tissue plasminogen activator delivered via catheter-directed thrombolysis (CDT) and/or pharmacomechanical thrombolysis (PMT), with other adjunctive endovascular or surgical interventions. Procedural success, thrombolysis duration, and 30-day and long-term outcomes were obtained for the whole series and were also compared between the CDT and PMT groups. Limb salvage and survival were assessed using time-to-event methods, including Kaplan-Meier estimation and Cox proportional hazards models. A total of 154 limbs were treated in 147 patients presenting with ALI (Rutherford class I, 9.7%; class IIa, 70.1%; class IIb, 20.1%). The mean follow-up was 15.20 months (range, 0.56-56.84 months). Indications for intervention included embolization (14.3%), thrombosed bypass (36.4%), thrombosed stent (26.6%), native artery thrombosis (24.0%), and thrombosed popliteal aneurysm (3.2%). Technical success was achieved in 83.8% of cases, with a 30-day mortality rate of 5.2%. Procedural complications included systemic bleeding (5.2%), access site hematoma (4.5%), acute renal failure (1.9%), and distal embolization (9.7%). The mean runoff score decreased from 13.42 preintervention to 7.43 postintervention. Adjuvant revascularization procedures were required in 89.0% of patients and were endovascular (68.8%), hybrid (9.1%), or open (11.0%). Only 3.2% of patients required a fasciotomy. The overall rate of major amputation was 15.0% (18.1% for CDT only, 11.3% for PMT; P = NS). Predictors of limb loss by Cox proportional hazards models included end-stage renal disease (hazard ratio [HR], 8.563; P < .001) and poor pedal outflow, with an incremental protective effect for improved pedal outflow (HR, 0.205; P < .001 for one pedal outflow vessel; HR, 0.074; P < .001 for ≥ two pedal outflow vessels). Gender, smoking, diabetes, Rutherford score, runoff score, thrombosed popliteal aneurysm, and PMT were not significant predictors of limb loss. The use of PMT was a significant predictor of technical success (odds ratio, 2.67; P = .046). Endovascular therapy with thrombolysis using tissue plasminogen activator remains an effective treatment option for patients presenting with mild or moderate lower extremity ALI, with equal benefit derived with CDT or PMT. Patients with end-stage renal disease or poor pedal outflow have an increased risk of limb loss and may benefit from alternative revascularization strategies.