Ultrasound Outcomes From ATTRACT Trial Published
August 7, 2019—An evaluation of the relationships of pharmacomechanical catheter-directed thrombolysis (PCDT), sonographic findings, and clinical outcomes in patients with acute proximal deep vein thrombosis (DVT) in the ATTRACT trial were published by Ido Weinberg, MD, et al online in Vascular Medicine.
The multicenter ATTRACT trial was composed of 692 patients with acute proximal DVT who were randomized to receive anticoagulation or anticoagulation plus PCDT. In December 2017, the 2-year follow-up data from the ATTRACT clinical trial were published by Suresh Vedantham, MD, et al in The New England Journal of Medicine (2017;377:2240–2252). The ATTRACT investigators concluded that among patients with acute proximal DVT, the addition of PCDT to anticoagulation did not result in a lower risk of postthrombotic syndrome (PTS) but did result in a higher risk of major bleeding.
As summarized in Vascular Medicine, the current study evaluated the relationships between endovascular therapy, duplex ultrasonography (DUS), PTS, and quality of life (QOL) as evaluated by the VEINES-QOL (Venous Insufficiency Epidemiological and Economic Study on Quality of Life) tool in ATTRACT. Compression DUS was performed at baseline, 1 month, and 12 months. Reflux DUS was performed at 12 months in a subset of 126 patients and adjudicated by the VasCore vascular core lab in Boston, Massachusetts. Clinical outcomes were collected over 24 months.
At 1 month, patients who received PCDT had less residual thrombus compared to control patients, evidenced by fewer noncompressible common femoral vein (CFV) (21% vs 35%; P < .0001), femoral vein (51% vs 70%; P < .0001), and popliteal vein (61% vs 74%; P < .0001) segments.
In the ultrasound substudy, the investigators found at 12 months that valvular reflux prevalence was similar between groups (85% vs 91%; P = .35).
CFV noncompressibility at 1 month was associated with higher rates of any PTS (61% vs 46%; P < .001), a higher incidence of moderate or severe PTS (30% vs 19%; P = .003), and worse QOL (difference 8.2 VEINES-QOL points; P = .004) at 24 months. Additionally, the presence of valvular reflux at 12 months was associated with moderate or severe PTS at 24 months (30% vs 0%; P = .01).
The investigators concluded that PCDT results in lower thrombus burden but does not reduce the prevalence of venous valvular reflux. Additionally, they noted that CFV noncompressibility at 1 month is associated with more PTS, more severe PTS, and worse QOL at 24 months. Valvular reflux may predispose to moderate or severe PTS, advised the investigators in Vascular Medicine.
Reviewing these findings with Endovascular Today, Dr. Weinberg (@angiologist), along with study coauthors Dr. Vedantham and Michael Jaff, DO (@docmrjaff), commented, "PTS can be a severe, debilitating complication of proximal DVT. To date, there are few options for prevention or treatment of PTS. Therefore, being able to predict which patients have a higher likelihood for developing significant PTS has clinical value. Furthermore, the mechanism of PTS is not clearly understood. In that context, the current manuscript offers some insight into the importance (and limitations) of venous patency and reflux. Further study into the mechanism, beyond maintaining patency, is likely needed if we want to one day be able to prevent and treat this condition."