Safety and Effectiveness of the ClotTriever System for Treating Deep Vein Thrombosis: Six-Month Outcomes of the Fully Enrolled CLOUT Registry

Sunday, March 5, 2023

4:12 PM – 4:21 PM

Location: Phoenix Convention Center, 221C

Featured Presenter(s)

Abdullah Shaikh, MD

Interventional Radiologist
Allegheny Health Network

Disclosure information not submitted.

Disclosure(s):

Abdullah Shaikh, MD: Becton Dickinson: Speaker's Bureau (); Inari Medical: Speaker's Bureau ()

Purpose: Mechanical thrombectomy is a lytic-free treatment option for deep vein thrombosis (DVT). This study presents 6-month outcomes of the fully enrolled 500-patient CLOUT registry.

Materials and Methods: The CLOUT registry is a prospective, all-comer study for lower extremity DVT patients treated with the ClotTriever System (Inari Medical, Irvine, CA). Primary effectiveness endpoint was complete or near-complete (≥75%) thrombus removal assessed by an independent core laboratory. Serious adverse events (SAE) were adjudicated by an independent medical monitor. Duplex ultrasound for flow and compressibility, revised venous clinical severity (rVCSS), Villalta scores to assess post-thrombotic syndrome (PTS), pain (NPRS), and EuroQoL group 5-D (EQ-5D) scores were assessed through 6 months.

Results: Of the analysis population (499 patients; 521 limbs; 43 US sites), 49.5% were male with mean age of 59.4±15.2. Prior DVT was present in 24.9% of patients and 29.7% were contraindicated to thrombolytics. Most patients (99.4%) were treated in a single session with median thrombectomy time of 26 minutes and blood loss of 40.0 mL. Only 11 (2.2%) patients required post-procedure ICU stay. The primary endpoint of ≥75% thrombus removal was seen in 91.2% of limbs, with complete thrombus removal in 63.8%. The 30-day SAE rate was 8.4% and procedure-related readmission rate was 4.2%. At 6 months, flow was present in 92.0% (vs 27.6% at baseline, P < 0.0001) and normal or partial compressibility improved to 91.5% (vs 28.0% at baseline, P < 0.0001) of limbs. Six-month median Villalta score was reduced to 1 (vs 9 at baseline, P < 0.0001). Median NPRS at 6 months was 0 (vs 5 at baseline, P < 0.001) and EQ-5D quality of life was 1 (vs 0.689 at baseline, P < 0.001). Additional outcomes are shown in Table 1.

Conclusion: The CLOUT registry demonstrates significant thrombus removal post-procedure, strong 30-day safety profile, and excellent 6-month outcomes including reduced pain, PTS severity, and improved quality of life. Study follow-up to 2 years is ongoing.