Real-World Clinical Outcomes of EKOS Catheter-Directed Thrombolysis versus Systemic Alteplase in Acute Pulmonary Embolism: A Retrospective Cohort Study

Tarek Mahmoud Senosy¹Eman Fathi Abd Razik¹Tarek Khairy Mosa²Ahmed Mahmoud Ali²Ahmed Ibrahim³Asmaa Elsayed^4*Engy Wahsh⁵

• ¹Minia University Faculty of Medicine, Menia Governorate, Egypt
• ²Ain Shams University Faculty of Medicine, Cairo, Egypt
• ³Department of Clinical Pharmacy, College of Pharmacy, King Khalid University, Abha 61421, Saudi Arabia, Abha, Saudi Arabia
• ⁴Faculty of Pharmacy, Sohag University, Sohag, Egypt
• ⁵October 6 University Faculty of Pharmacy, 6th of October City, Egypt

Background: The use of EKOS (EkoSonic Endovascular System) in patients with pulmonary embolism (PE) has shown promising outcomes by combining ultrasound technology with catheter-directed thrombolysis to dissolve clots effectively. This method targets thrombus removal precisely, minimizing the systemic exposure to thrombolytic agents and thereby reducing bleeding risks. Given its minimally invasive approach and focused delivery, EKOS offers a safer alternative for intermediate high-risk patients where traditional anticoagulation or systemic thrombolysis may pose higher risks of complications. This study compares the safety and effectiveness of EKOS versus intravenous (IV) alteplase infusion in managing acute PE. Methods: A retrospective cohort study was conducted at a tertiary hospital, examining patient records from 2022 to 2024 according to predefined eligibility criteria. Individuals aged 18 years or older diagnosed with intermediate-to high-risk PE who showed clinical deterioration after 48 hours of anticoagulation were enrolled, as assessed by the National Early Waning Score (NEWS). Patients were ruled out if they had a stable PE or were at high risk of hemodynamic decompensation at the time of presentation. The primary outcomes were the change in Tricuspid annular plane systolic excursion (TAPSE) and RV to Left ventricular (RV/LV) diameter ratio from baseline to one-week outpatient follow-up. Results: Out of 104 eligible patients, 54 received EKOS (EKOS group), and 50 received IV alteplase infusion (control group). The RV/LV diameter ratio significantly decreased, while TAPSE improved significantly in both the EKOS and control groups. At the end of follow-up, Major bleeding events within 72 hours were significantly lower in the EKOS group (2 vs. 8; P = 0.03). Although all-cause mortality at 6 months was lower in the EKOS group, the difference was not statistically significant (P = 0.3). Conclusions: EKOS showed comparable efficacy to systemic thrombolysis, reducing right heart strain, improving RV function, and minimizing complications in patients with intermediate high-risk PE after failed anticoagulation, with deterioration in clinical condition and need for rescue thrombolysis. Also, EKOS had a lower incidence of major bleeding within 72 hours, making it a safer option for rescue thrombolysis.