December 19, 2019
Quality-of-Life Analysis Published From ATTRACT Trial of Pharmacomechanical Catheter-Directed Thrombolysis of Proximal DVT
December 19, 2019—The Society for Vascular Surgery (SVS) announced that the findings from a quality-of-life (QOL) analysis of data from the ATTRACT trial were published by Susan R. Kahn, MD, et al in Journal of Vascular Surgery: Venous and Lymphatic Disorders (2019;8:8–23.e18).
The study shows that QOL measurements improved after pharmacomechanical catheter-directed thrombolysis (PCDT), particularly in early follow-up and for iliofemoral deep venous thrombosis (DVT).
According to the SVS announcement, the ATTRACT trial investigators sought to determine the value of PCDT in treating proximal DVT. Although the trial did not show a significant decrease in the syndrome at 2 years after treatment, it did observe a reduction in its severity and an accelerated resolution of acute symptoms.
The ATTRACT trial was composed of patients enrolled and managed at 56 hospitals in the United States. Investigators were led by Dr. Kahn, who is with Jewish General Hospital in Montreal, Quebec, Canada. As summarized in the SVS announcement, a total of 692 patients were evaluated between 2009 and 2014, with follow-up at 1, 6, 12, 18 and 24 months. Through randomization, 337 patients were allocated to PCDT and 355 to no PCDT. General patient demographics showed a patient population that was a mean age of 53 years and 62% male, as well as 57% iliofemoral DVT versus 43% femoropopliteal DVT.
For the group as a whole, Venous Insufficiency Epidemiological and Economic Study (VEINES)–QOL scores for those undergoing PCDT versus no PCDT showed significant improvement at 1 and 6 months (difference 5.7 and 5.1 points, respectively) but no difference at the later time intervals.
The investigators also provided a subgroup analysis, separating the iliofemoral from femoropopliteal DVT. For iliofemoral DVT, VEINES-QOL scores were improved significantly for those undergoing PCDT versus no PCDT at each time point: a 10-point difference at 1 month, 8.8 points at 6 months, 5.8 points at 18 months, and 5.6 points at 24 months. In contrast, for femoropopliteal DVT, there was no difference in the QOL score between the treatment groups at any time point.
Addressing the reasons why PCDT might have improved venous QOL even though it did not prevent postthrombotic syndrome, Dr. Kahn stated in the SVS announcement, “First, most of the improvement in QOL was in the first 6 months, and the trial did find that PCDT reduced clot burden, early leg pain, and swelling over no PCDT and was associated with a reduced point prevalence of PTS at 6 months—but not thereafter. Though PCDT did not prevent PTS, it did reduce its severity.”
The decision to proceed with lytic therapy for patients with iliofemoral DVT can be complicated. These data support offering this therapy to selected patients with severe symptoms, low bleeding risk, and a willingness to undergo a catheter-based procedure, noted the SVS announcement.
Discussing the findings with Endovascular Today, Dr. Kahn commented, “This analysis focused on detailed QOL outcomes among ATTRACT trial participants. In the main trial results, PCDT did not reduce the occurrence of postthrombotic syndrome compared to no PCDT. In this analysis, QOL improvement was better with PCDT than no PCDT at earlier but not later follow-up visits in the whole population, and QOL improvement was better with PCDT than no PCDT throughout follow-up in iliofemoral DVT patients. An interesting next step would be to better understand how DVT patients would weigh these QOL results.”