Ultrasound-assisted versus conventional catheter-directed thrombolysis for acute iliofemoral deep vein thrombosis: 1-year follow-up data of a randomized-controlled trial

Background: In patients with acute iliofemoral deep vein thrombosis (IFDVT), catheter-directed thrombolysis (CDT) aims to prevent the postthrombotic syndrome (PTS). Adding intravascular high-frequency, low-power ultrasound energy to CDT does not seem to improve the immediate thrombolysis results but its impact on clinical outcomes at 12 months is not known. Patients/Methods: In this randomized-controlled trial, 48 patients (mean age 50 +/- 21 years; 52% women) with acute IFDVT were randomized to conventional CDT (n = 24) or ultrasound-assisted CDT (USAT; n = 24). In both groups, a fixed-dose thrombolysis regimen (20 mg r-tPA over 15 h) was used, followed by routine stenting of residual venous obstruction. At 12 months, PTS and venous disease severity (Villalta score and revised Venous Clinical Severity Score [rVCSS]), disease-specific quality of live (IQOL; CIVIQ-20) and duplex-sonographic outcomes were assessed. Results: Among the 45 surviving patients, 40 (89%; 95% confidence interval [CI] 76-96%) patients were free from PTS (defined as Villalta score < 5 points; 83%, 95% CI 61-95% in the USAT and 96%, 95% CI 77-100% in the CDT group), with a similar mean total Villalta score of 2.3 +/- 2.9 vs. 1.7 +/- 1.6, and a mean total rVCSS of 3.0 +/- 3.5 vs. 2.7 +/- 2.9 in the USAT and the CDT groups, respectively. Both groups had good disease-specific QOL with a CIVIQ-20 score of 29.4 +/- 11.8 vs. 26.1 +/- 7.8, respectively. Primary (100% vs. 92%) and secondary (100% vs. 96%) iliofemoral patency rates and presence of femoro-popliteal venous reflux (39% vs. 33%) were similar in both groups. Conclusion: The addition of intravascular ultrasound energy to conventional CDT for the treatment of acute IFDVT did not have any impact on relevant clinical or duplex sonographic outcomes, which were favorable in both study groups.