Analysis of clinical outcomes utilizing ultrasound-assisted catheter-directed thrombolysis for pulmonary embolism

1. In this cohort of patients with a pulmonary embolism (PE), ultrasound catheter-directed thrombolysis (USAT) is safe for symptomatic patients with intermediate-high and high-risk acute PE. 

Evidence Rating Level: 1 (Excellent) 

Immediate thrombolytic therapy by intravenous injection of a plasminogen activator is a commonly used treatment to restore blood flow in patients with massive pulmonary embolism (PE). However, systemic thrombolysis is associated with a significant bleeding risk, so appropriate therapy is often delayed to prevent bleeding. To improve safety outcomes, this study assessed the benefits and risks of ultrasound catheter-directed thrombolysis (USAT) in patients with PE. Eligibility for USAT required a diagnosis of acute PE within 14 days of symptom onset, along with evidence of proximal central or segmental filling defects on imaging, suggestive of PE on imaging. The EkoSonic Endovascular System (EKOS) was used to perform USAT following a standardized protocol to enhance lytic efficacy. In-hospital mortality was the main outcome assessed, with periprocedural mortality and other adverse outcomes also evaluated. The study enrolled 315 patients (mean age 64.3±14.2 years); 257 (82%) with intermediate-high risk, and 58 (18%) with high-risk PE. Patients exhibited tachycardia (heart rate 104.3±20.4 bpm), hypoxemia (mean peripheral oxygen saturation 89.2%±7.5%), elevated mean pulmonary and arterial pressure (30.7±8.0 mm Hg), and reduced mixed venous oxygen saturation (58.5%±10.2%). A total of 10 participants (3.2%) died in the hospital, with an additional 2 patients dying in the periprocedural phase. Several participants experienced secondary outcomes including stroke (0.3%), bleeding (7.9%) and recurrent PE (1.0%). This study may be limited in generalizability since participants were only selected from one center with an established PE team. Despite this, the results demonstrate that USAT is a safe and effective treatment in patients with intermediate-high and high-risk acute PE. 

Click to read the study in JAHA

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