Contemporary trends and outcomes of thrombolytic therapy for acute lower extremity ischemia

Abstract

Objective: Acute limb ischemia is a common vascular emergency requiring immediate intervention. Thrombolysis has been widely utilized for acute limb ischemia; the purpose of this study is to analyze contemporary trends, outcomes and complications of thrombolysis for acute limb ischemia.

Methods: Patients were identified from the Nationwide Inpatient Sample (2003-2013) using ICD-9. Patients undergoing emergency thrombolysis for acute limb ischemia were evaluated. Three groups were analyzed: thrombolysis alone, thrombolysis and endovascular procedure (T+ENDO), and failed thrombolysis requiring open surgery (T+OPEN).

Results: A total of 162,240 patients with acute limb ischemia were estimated: 33,615 patients (20.7%) underwent thrombolysis as the initial treatment. Mean age was 66.2 ± 34.9 years with 54% male. The utilization of thrombolysis increased significantly during the study period (16.8-24.2%, p < 0.0001). The most common group was thrombolysis and endovascular procedure (40.7%), followed by thrombolysis alone (34.1%), and T+OPEN (25.2%). Thrombolysis and endovascular procedure increased significantly over time (31.6-47.8%, p < 0.0001) whereas thrombolysis alone and T+OPEN significantly decreased (39.6-28.6% and 28.7-23.6%, respectively, p < 0.0001). Overall mortality was 4.9%; thrombolysis and endovascular procedure compared to thrombolysis alone and T-OPEN had a lower mortality rate (3.2% vs. 6.1% and 5.9%, p < 0001). The overall stroke rate was 1.9%; thrombolysis alone had the highest stroke rate (3.0%, p < 0.0001) with thrombolysis and endovascular procedure the lowest (1.2%) and T+OPEN 1.7%. The highest amputation rate was T+OPEN (11.6%, p < 0.001) compared to thrombolysis and endovascular procedure (5.1%) and thrombolysis alone (5.3%). T+OPEN had the highest incidence of cardiac (5.5%), respiratory (7.3%) and renal complications (12.5%), pneumonia (4.0%), and fasciotomy (16.8%) (all p < 0.0001).

Conclusion: Thrombolysis remains an effective treatment for acute limb ischemia with increased utilization over time. There was a significant increase in thrombolysis and endovascular procedure leading to improved outcomes. Thrombolysis alone carried the highest mortality and stroke rate, with T+OPEN associated with the highest amputation and complications. Although thrombolysis is effective, 25% of patients required an open procedure suggesting that patient selection for thrombolysis first instead of open surgery continues to be a clinical challenge.

Keywords: Acute limb ischemia; acute lower extremity ischemia; thrombolysis.