Continuous VTE Risk Observed After Lower Extremity Revascularization in Patients with PAD

Connie N. Hess, MD

A recent cohort study reported a continuous risk for venous thromboembolism (VTE) after lower extremity revascularization (LER) in patients with peripheral artery disease (PAD), with more risk for patients who were older, had obesity, and more severe PAD.

The findings suggest low-dose rivaroxaban plus aspirin was associated with lower VTE risk compared with aspirin alone and those benefits appeared earlier and continued over time.

“These findings provide a more complete understanding of the true spectrum of thrombotic risk facing patients with PAD undergoing revascularization and may help to identify patients at higher risk for VTE after LER,” wrote study author Connie N. Hess, MD, Division of Cardiology, Department of Medicine, University of Colorado School of Medicine.

There have been reported associations between the burden of atherosclerotic vascular disease and the risk of VTE, but this association has not been described fully in PAD after LER.

The current cohort study was a prespecified analysis of the VOYAGER-PAD study, in which patients aged ≥50 years with symptomatic PAD who underwent successful were enrolled from 2015 to 2018. Exclusion crtieria included planned dual antiplatelet therapy for ≥6 months and the need for systemic anticoagulation.

Patients were randomized to rivaroxaban 2.5 mg twice daily or placebo with a background of aspirin 100 mg daily. The analysis used symptomatic VTE as the primary end point, where VTE severity was classified according to hospitalization or death within 30 days of the VTE event.

A total of 6564 patients were randomized in VOYAGER PAD and had a follow-up at a median of 28 months. Within that time frame, 66 patients (1.0%) had at least 1 VTE event and the incidence of VTE was 0.42 per 100 patient-years.

Those with VTE were found to be older (median age, 68 years), had greater body weight (7.6% with weight ≤60 kg), and more frequently had hypertension (90.9% vs 81.3%), as well as more severe PAD.

Data from VOYAGER PAD show rivaroxaban was associated with a 39% lower risk of VTE (hazard ratio [HR], 0.61; 95% CI, 0.37 - 0.998; P = .047). The 3-year event rate of VTE in patients receiving placebo was 1.7% and investigators noted the pattern of risk was linear (year 1: 0.5%; year 2: 1.1%).

In a multivariable model, investigators found baseline factors independently associated with VTE risk consisted of:

• Weight (HR, 3.04; 95% CI, 1.09 - 8.43)
• Hypertension (HR, 2.11; 95% CI, 0.91 - 4.89)
• Prior amputation (HR, 2.07; 95% CI, 0.95 - 4.53)
• Older age (HR, 1.81; 95% CI, 1.06 - 3.11)

However, clopidogrel use at randomization was not associated with VTE risk (HR, 0.66; 95% CI, 0.41 - 1.08), but rivaroxaban use was associated with VTE risk (HR, 0.60; 95% CI, 0.37 - 0.998; P = .047).

When investigators adjusted for those factors significantly associated with VTE, they found VTE was associated with a significantly increased risk of subsequent mortality (HR, 7.22; 95% CI, 4.66 - 11.19).

“The spectrum of venous and arterial thrombotic events and overall benefits of more potent antithrombotic strategies for prevention should be considered after LER for PAD,” Hess added.

The study, “Rivaraoxaban and Risk of Venous Thromboembolism in Patients with Symptomatic Peripheral Artery Disease After Lower Extremity Revascularization,” was published in JAMA Network Open.