CLOUT Registry’s 2-Year Outcomes Reported for Inari’s ClotTriever to Treat DVT

November 4, 2024—Two-year outcomes were reported from the CLOUT registry, which is a prospective, multicenter study evaluating patient outcomes after mechanical thrombectomy (MT) with the ClotTriever system (Inari Medical) in proximal lower extremity deep vein thrombosis (DVT).

David J. Dexter, MD, presented the CLOUT findings in the second late-breaking clinical trials session at VIVA24, the 22nd annual Vascular InterVentional Advances annual vascular education symposium held by The VIVA Foundation on November 3-6 in Las Vegas, Nevada.

The VIVA24 press release noted that prospective data detailing long-term outcomes after endovascular treatment for DVT are limited because of the field’s relatively recent development.

According to VIVA24, this presentation represents the largest available data set detailing MT outcomes for DVT and the first reporting of final results through 2 years from all available patients enrolled in the completed CLOUT registry.

Study inclusion was all-comer: patients were aged ≥ 18 years and enrolled regardless of bilateral disease, duration of symptoms, previous treatment for the current DVT, or contraindications to thrombolytic therapy. In total, 285 patients completed the 2-year follow-up visit.

The VIVA24 press summarized the findings at 2 years post-MT, as follows:

• 81.5% of treated limbs had no post-thrombotic syndrome (PTS; Villalta score < 5) compared to 18.8% at baseline.
• The prevalence of moderate or severe PTS (Villalta score ≥ 10) was 6.4% compared to 46.9% at baseline.
• Flow was demonstrated in 93.9% of treated vessels and compressibility in 96.2% via duplex ultrasound assessment.
• Additional significant improvements were observed in revised Venous Clinical Severity Score, Numeric Pain Rating Scale, and EQ-5D scores when compared to baseline.

The CLOUT study concluded that these real-world data detailing MT for DVT outcomes with the ClotTriever system demonstrate significant symptom relief and quality-of-life improvement for patients in addition to recovery of vessel function and a low rate of subsequent PTS. Furthermore, such favorable long-term outcomes coupled with previously reported acute safety and effectiveness profiles support MT treatment for DVT.

Definitive evidence comparing MT with Inari’s ClotTriever plus anticoagulation to anticoagulation alone will come from the currently enrolling DEFIANCE randomized controlled trial, noted the VIVA24 press release.