IP225. Real-World Outcomes of EKOS Ultrasound-Enhanced Catheter-Directed Thrombolysis for Acute Limb Ischemia

Abstract

Ultrasound-enhanced catheter-directed thrombolysis (UET) using the EKOS device (EKOS Corporation, Bothell, Wash) for acute peripheral artery ischemia has been purported in clinical trials to accelerate the fibrinolytic process to reduce treatment time and lytic dosage. However, UET performance in a real-world clinical setting has thus far been inadequately described. We performed a retrospective review of all patients undergoing UET for acute limb ischemia at a single institution during a 5-year period. Data collected included patients' demographics, procedural details, and 30-day and 1-year outcomes. Primary outcomes were major bleeding events, limb salvage, and mortality. We identified 32 patients (mean age, 67.4 ± 14.9 years; 25% female) who underwent UET for acute limb ischemia between 2014 and 2018. At presentation, 43.8% were therapeutically anticoagulated. Rutherford acute limb ischemia classification was I in 56.3%, IIa in 25.0%, and IIb in 18.8%. Etiology was thrombosis of native artery in 12.5% of patients, infrainguinal prosthetic bypass in 31.3%, infrainguinal autogenous bypass in 6.3%, and stented native vessel in 50.0%. Mean duration of thrombolytic therapy was 22.2 ± 11.3 hours, and mean tissue plasminogen activator dose was 24.5 ± 15.3 mg. In-line flow to the foot was re-established in 90.6% of patients with a significant improvement in preoperative to postoperative ankle-brachial index (0.31 ± 0.29 vs 0.78 ± 0.34; P < .001) and number of patent tibial runoff vessels (1.31 ± 1.20 vs 1.96 ± 0.86; P < .001; Fig). There was no significant difference in revascularization success between occluded vessel types: native vessel, 75% success; stented vessel, 93.8%, autogenous bypass, 100%, and prosthetic bypass, 90% (P = .48). Major bleeding complications occurred in three patients (9.4%), including two intracranial hemorrhages (6.3%). Limb salvage at 30 days and 1 year was 93.8% and 87.5%, respectively. Ipsilateral reintervention was required in 37.5% of patients within 1 year. Overall mortality was 6.2% at 30 days and 13.5% at 1 year, and mortality was significantly higher in patients with higher Rutherford class (P = .049). UET with the EKOS device demonstrates acceptable real-world outcomes in the treatment of acute limb ischemia. UET is generally safe, with a low rate of associated hemorrhagic complications, and is effective at re-establishing in-line flow to yield high limb salvage rates. However, UET is associated with a high rate of reintervention within 1 year. Further investigation is needed into specific predictors of limb salvage and need for reintervention as well as cost-efficacy of this technology compared with traditional methods.