Impact of coincident lower extremity deep vein thrombosis on symptomatic and incidental pulmonary embolism outcomes. A single-center prospective cohort study.

Background: The prognostic implications of co-incident DVT at the time of PE diagnosis remains unclear.

Objectives: Study aims were to assess the impact of co-incident lower extremity (LE) deep vein thrombosis (DVT) on clinical outcomes of pulmonary embolism (PE) including venous thromboembolism (VTE) recurrence and mortality.

Methods: Consecutive patients with confirmed acute symptomatic or incidental PE (March 1, 2013 to June 30, 2021) who underwent ultrasound imaging were divided into two groups depending on the presence or absence of LE DVT. Patients were followed prospectively for VTE recurrence, bleeding, and all-cause mortality.

Results: Over the study period, 1907 patients with PE were stratified into groups based on the presence (n = 920) or absence (n = 987) of LE DVT. Patients with co-incident LE DVT were older, heavier, and had a significantly greater frequency of trauma, confinement, thrombophilia, and VTE. Those without LE DVT had a higher prevalence of active cancer, metastatic disease, and active systemic therapy use. All-cause mortality rates (per 100 person-years) were significantly higher for patients without vs with co-incident LE DVT (42.4/100 person-years vs 29.6/100 person- years; P < .001) with no differences in VTE recurrence or bleeding outcomes. After stratification by cancer status, mortality in those without vs. with co-incident DVT only remained significant among noncancer patients (15.2/100 person-years vs 12.1/100 person-years, P = .046).

Conclusions: Among patients with acute PE, the absence of co-incident lower extremity DVT is associated with significantly higher mortality rates. Mortality rate differences were only observed for those without cancer. No differences in VTE recurrence or bleeding were observed.