Safety and Effectiveness of Mechanical Thrombectomy From the Fully Enrolled Multicenter, Prospective CLOUT Registry

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Journal of the Society for Cardiovascular Angiography & Intervention


Background: We report in-hospital outcomes from the multicenter, prospective, single-arm ClotTriever Outcomes (CLOUT) registry, which enrolled up to 500 patients with proximal lower extremity deep vein thrombosis (DVT) treated with percutaneous mechanical thrombectomy using the ClotTriever System (Inari Medical). Methods: The CLOUT registry enrolled all-comer patients with DVT, irrespective of symptom duration, thrombus age, prior treatment of the current DVT, or bilateral thrombus. The primary effectiveness end point was defined as complete or near complete (≥75%) reduction in Marder score. Thrombus burden was assessed by an independent core laboratory. Mortality and serious adverse events, including device-relatedness, were adjudicated by an independent medical monitor. Here, safety and outcomes are evaluated through discharge. Results: The median age was 61.9 years (IQR, 48.0-70.8), 50.5% were women, 24.9% had a history of DVT, and 23.2% had previously failed treatment of the current DVT. Nearly all procedures (99.4%) were performed in a single session with negligible procedural blood loss (median 40.0 mL; IQR, 20.0-50.0), and most patients (97.8%) required no subsequent intensive care unit monitoring. The primary effectiveness end point was achieved in 91.2% of limbs. Through discharge, 1 device-related serious adverse event (0.2%) occurred. Health status, as assessed by self-reported pain and circumferential measurements of limb edema, were significantly improved at discharge. Conclusions: Thrombectomy with the ClotTriever System is a safe and effective treatment for proximal lower extremity DVT, while also avoiding the need of intensive care. Early patient improvements are demonstrated, and follow-up is ongoing to 2 years.





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