LB01 - A Randomized Controlled Trial of Structured Exercise to Prevent Post-Thrombotic Syndrome After Acute Deep Vein Thrombosis (EFFORT-2)

Objectives: In patients with acute lower extremity deep vein thrombosis (LE-DVT), standard-of-care anticoagulation (AC) reduces pulmonary embolism, but does not promote thrombus resolution. Incomplete thrombus resolution entraps venous valves and causes venous reflux and obstruction, which lead to post-thrombotic syndrome (PTS) in 25-50% of patients. Therefore, increasing thrombus resolution may improve long-term outcomes. We have shown that aerobic exercise increases venous flow, which accelerates thrombus resolution through enhanced fibrinolysis. We therefore conducted a randomized controlled trial comparing rates of PTS one year after standard AC versus a combination of AC plus aerobic exercise (EX) in patients with acute LE DVT. The primary outcome was the rate of occurrence of moderate or severe PTS (defined as a Villalta score of ≥10) at one year of follow-up.

Methods: Patients with acute LE-DVT (within the previous 30 days) were randomized 1:1 to AC alone or AC plus EX. Aerobic exercise comprised 30 minutes of treadmill-walking to achieve at least 50% of predicted VO2Max, three times/week for three months. Patients were evaluated one year post-enrollment for PTS using the Villalta score. We compared the rates of moderate or severe PTS (Villalta score of ≥10) between the two groups using Fisher’s exact test. Key adverse events were also tracked.

Results: A total of 102 patients were enrolled; nine patients were lost to follow-up (8.8%). The mean age of the entire cohort was 53.8 ± 13.7 years, and 63 patients (62%) were males. The AC and EX groups were well-matched, without significant differences with respect to age, sex, body mass index, or thrombophilic states. One-year Villalta scores were available for 93 patients (control n= 48; exercise n= 45). Moderate or severe PTS (Villalta score ≥10) occurred exclusively in the AC group (12.5% vs 0% in the EX group; p= 0.027). At one year, the mean ± SD Villalta score was 2.11 ± 2.06 in the EX group and 3.83 ± 4.37 in the AC group. No exercise-related injuries, hospitalizations, or mortalities occurred, and adverse events were comparable between groups (Table 1).

Conclusions: Early structured moderate-intensity aerobic exercise in addition to standard anticoagulation in patients with acute lower extremity DVT is associated with a significant reduction in the rates of moderate or severe PTS at one year, and a numeric reduction in the overall severity of post-thrombotic syndrome. These findings suggest that exercise represents a simple, low-risk adjunctive strategy to improve long-term outcomes following acute DVT.