Comparison of anticoagulation vs mechanical thrombectomy for the treatment of iliofemoral deep vein thrombosis

Abstract

Objective: To compare the comparative effects of treatment with contemporary mechanical thrombectomy (MT) or anticoagulation (AC) on Villalta scores and post-thrombotic syndrome (PTS) incidence through 12 months in iliofemoral deep vein thrombosis (DVT).

Methods: Patients with DVT in the Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis (ATTRACT) randomized trial and the ClotTriever Outcomes (CLOUT) registry were included in this analysis. Both studies evaluated the effects of thrombus removal on the incidence of PTS. Patients with bilateral DVT, isolated femoral-popliteal DVT, symptom duration of >4 weeks, or incomplete case data for matching covariates were excluded. Propensity scores were used to match patients 1:1 who received AC (from ATTRACT) with those treated with mechanical thrombectomy (from CLOUT) using nearest neighbor matching on nine baseline covariates, including age, body mass index, leg treated, provoked DVT, prior venous thromboembolism, race, sex, Villalta score, and symptom duration. Clinical outcomes, including Villalta score and PTS, were assessed. Logistic regression was used to estimate the likelihood of developing PTS at 12 months.

Results: A total of 164 pairs were matched, with no significant differences in baseline characteristics after matching. There were fewer patients with any PTS at 6 months (19% vs 46%; P < .001) and 12 months (17% vs 38%; P < .001) in the MT treatment group. Modeling revealed that, after adjusting for baseline Villalta scores, patients treated with AC had significantly higher odds of developing any PTS (odds ratio, 3.1; 95% confidence interval, 1.5-6.2; P = .002) or moderate to severe PTS (odds ratio, 3.1; 95% confidence interval, 1.1-8.4; P = .027) at 12 months compared with those treated with MT. Mean Villalta scores were lower through 12 months among those receiving MT vs AC (3.3 vs 6.3 at 30 days, 2.5 vs 5.5 at 6 months, and 2.6 vs 4.9 at 12 months; P < .001 for all).

Conclusions: MT treatment of iliofemoral DVT was associated with significantly lower Villalta scores and a lower incidence of PTS through 12 months compared with treatment using AC. Results from currently enrolling clinical trials will further clarify the role of these therapies in the prevention of PTS after an acute DVT event.

Keywords: Anticoagulation; Deep vein thrombosis; Mechanical thrombectomy; Post-thrombotic syndrome; Propensity score matching.

Fig 1

Patient matching study design. AC, anticoagulation plus compression; BMI, body mass index; MT, mechanical thrombectomy; VTE, venous thromboembolism. Populations before and after applying exclusion criteria and propensity score matching on nine matching variables.

Fig 2

Matched cohort Villalta score categories and PTS incidence through 12 months by treatment. AC, anticoagulation plus compression; MT, mechanical thrombectomy; PTS, post-thrombotic syndrome. Categorical Villalta scores through 12 months for matched patients treated with AC or MT. Patients with Villalta scores of 5+ or 10+ at 6 or 12 months were identified as having any or moderate to severe PTS syndrome, respectively.

Fig 3

Estimated probability of developing PTS at 1 year by treatment and baseline Villalta score. AC, anticoagulation plus compression; MT, mechanical thrombectomy; PTS, post-thrombotic syndrome. Logistic regression estimated probability of developing any PTS (A) or moderate to severe PTS (B) at 1 year by treatment and baseline Villalta score. Circles represent estimated probability of developing PTS for each matched patient in the model.

Fig 4

Matched cohort mean Villalta scores through 12 months by treatment. AC, anticoagulation plus compression; MT, mechanical thrombectomy. Mean Villalta scores through 12 months for matched patients treated with AC or MT.

Fig 5

Change in calf edema from baseline through 30 days by treatment. AC, anticoagulation plus compression; MT, mechanical thrombectomy. Change in calf edema from baseline at 10 days (AC only), discharge (MT only), and 30 days (AC and MT) by treatment type.

Supplementary Figure (online only)

Comparison of standardized mean differences before and after propensity score matching. BMI, body mass index; DVT, deep vein thrombosis; VTE, venous thromboembolism.