A new study, recently published online in the journal Circulation, reports on outcomes from a subgroup of 391 patients with acute iliofemoral deep venous thrombosis (DVT) in whom pharmacomechanical catheter-directed thrombolysis (PCDT) was evaluated within the ATTRACT trial.
The authors, Anthony Comerota and colleagues, reveal that in patients with acute iliofemoral DVT, “PCDT does not influence the occurrence of the post-thrombotic syndrome (PTS) or recurrent venous thromboembolism (VTE) through 24 months.” However, as reported in the journal, the authors write: “In patients with acute iliofemoral DVT, PCDT does appear to provide greater reduction in acute leg pain and swelling through 30 days’ follow-up, as well as reduced PTS severity, reduced moderate-or-severe PTS, and greater improvement in venous disease specific quality of life through 24 months.”
As outlined in the journal, the clinical implications note that these findings support early use of PCDT in patients with acute iliofemoral DVT who have severe symptoms, low bleeding risk, and who attach greater importance to a reduction in early and late symptoms than to the risks, costs, and inconvenience of PCDT.
As reported in Venous News, the ATTRACT trial previously indicated that PCDT did not prevent the post-thrombotic syndrome (PTS) in patients with acute proximal DVT.
Comerota and colleagues outline the methods used: “Within a large multicentre, randomised trial, 391 patients with acute DVT involving the iliac and/or common femoral veins were randomised to PCDT with anticoagulation vs. anticoagulation alone (No-PCDT) and were followed for 24 months to compare short-term and long-term outcomes.”
The main results are summarised as follows:
The researchers note that between six and 24 months, there was no difference in the occurrence of PTS (Villalta scale >5 or ulcer: 49% PCDT vs. 51% No-PCDT; p=0.59).
PCDT led to reduced PTS severity as shown by: lower mean Villalta and venous clinical severity scores [VCSS] (p<0.01 for comparisons at six, 12, 18, and 24 months; and fewer patients with moderate-or-severe PTS (Villalta scale >10 or ulcer: 18% vs. 28%; 0.021) or severe PTS (Villalta scale >15 or ulcer: 8.7% vs. 15%, p=0.048; and VCSS >8: 6.6% vs. 14%; p=0.013).
From baseline, PCDT led to greater reduction in leg pain and swelling (p<0.01 for comparisons at 10 and 30 days) and greater improvement in venous disease specific quality of life (QOL) (VEINES-QOL unit difference 5.6 through 24 months, p=0.029), but no difference in generic QOL (p> 0.2 for comparisons of SF-36 mental and physical component summary scores through 24 months).
In patients having PCDT vs. No-PCDT, major bleeding within 10 days occurred in 1.5% vs. 0.5% (p=0.32), and recurrent venous thromboembolism over 24 months was observed in 13% vs. 9.2% (p=0.21).
Suresh Vedantham, Mallinckrodt Institute of Radiology, Washington University in St Louis, USA, and national principal investigator of ATTRACT told Venous News: “At all evaluated time points during the 24 months of follow-up, the symptoms and signs of venous disease were reduced in the patients with acute iliofemoral DVT who received early thrombus removal with PCDT. Given the absence of a PTS-prevention effect and the known risks of thrombolytic therapy, the first-line use of PCDT for iliofemoral DVT may be best considered on an individual basis for patients with low bleeding risk and severe leg symptoms causing functional limitations. When this is done, thanks to the ATTRACT investigators, it will constitute evidence-based therapy for the first time in the 25 years since catheter-directed DVT therapy was introduced. Further studies will help us better understand the magnitude and clinical importance of the long-term treatment effects.”