Inari’s ClotTriever for DVT Evaluated at 1 Year in CLOUT Registry

October 30, 2023—The CLOUT (ClotTriever Outcomes) registry is a prospective, multicenter study evaluating patient outcomes for proximal lower extremity deep vein thrombosis (DVT) treated with mechanical thrombectomy (MT) using the ClotTriever system (Inari Medical).

The 1-year clinical outcomes from the study were presented by David J. Dexter, MD, at The VEINS (Venous Endovascular Interventional Strategies) annual venous education symposium held by The VIVA Foundation on October 28-30 in Las Vegas, Nevada.

The VEINS press release noted that long-term, prospective outcome data after MT for DVT are lacking although positive results from CLOUT have been previously published. At The VEINS conference in 2022, Dr. Dexter presented in-hospital and 30-day outcomes from the fully enrolled registry.

At The VEINS 2023 symposium, Dr. Dexter provided the first report of 1-year outcomes for all available patients. Patients in CLOUT were aged ≥ 18 years and enrolled regardless of bilateral disease, duration of symptoms, previous treatment failure for the current DVT event, or contraindications to thrombolytic therapy. A total of 310 patients completed the 1-year follow-up visit.

In the findings at 1 year after MT, moderate-to-severe post-thrombotic syndrome (PTS; Villalta score ≥ 10) was observed in 8.8% of treated limbs. The overall PTS rate (Villalta score ≥ 5) was 19.3%

Venous patency, as measured by the presence of flow with normal or partial compressibility on duplex ultrasound, was observed in 94.2% of patients. Additionally, significant improvements were seen from baseline in revised Venous Clinical Severity Score, Numeric Pain Rating Scale score, and EQ-5D questionnaire score.

Dr. Dexter concluded that in the real-world, all-comer CLOUT registry, 1-year outcomes demonstrated a low rate of PTS after treatment with the ClotTriever system, which were complemented by patient-centric improvements in symptom relief and quality of life.

The VEINS press release advised that follow-up through 2 years is ongoing in the CLOUT registry. Additionally, the favorable 1-year clinical outcomes highlight the need for randomized controlled trial data comparing MT with standard of care anticoagulation treatment.

The recently initiated DEFIANCE randomized controlled trial will compare the ClotTriever system to anticoagulation for the treatment of symptomatic iliofemoral DVT, noted the press release from The VEINS symposium.