Pulmonary Embolism in Patients with Chronic Obstructive Pulmonary Disease Exacerbation

Abstract

Pulmonary embolism (PE) and acute exacerbation of chronic obstructive pulmonary disease (AECOPD) are two diseases that share similar symptoms which makes the diagnosis of PE challenging. AECOPD is a risk factor for PE, and PE diagnosed in the context of an exacerbation is associated with an increased risk of mortality. Current available PE diagnostic strategies have not been specifically derived and validated in this population. The overall objective of my research program, which include 6 projects, was to determine the optimal management of patients with a suspicion of PE among patients with AECOPD. Project 1 clarified the epidemiology and the burden of PE in patients with AECOPD in North America. It showed that the prevalence of PE in a Canadian center was 1.1% and that in patients with AECOPD, mortality was higher among those diagnosed with PE compared to those without PE. Project 2 and Project 3 presented the performance of available PE diagnostic strategies in patients with chronic lung disease and AECOPD, respectively. These two studies showed that standard diagnostic algorithms were safe, but a high proportion of patients would need imaging to rule out PE. Project 4 evaluated the association between PE and the type of AECOPD and showed that the risk of PE was clinically lower in patients with purulent AECOPD compared to patients with non-purulent/unknown etiology AECOPD. Project 5 presented the derivation of a new diagnostic strategy specifically for patients with AECOPD. The diagnostic strategy consists of a COPD-specific score (type of AECOPD, alternative diagnosis less likely than PE, and clinical signs of deep venous thrombosis) combined with D-dimer testing. Project 6 focused on the feasibility and challenges of a pilot study evaluating prospectively the prevalence of PE in these patients. The study demonstrated its feasibility and targeted challenges such as recruitment of patients, adequate pre-test probability assessment and consistent PE diagnostic strategy use. All 6 projects helped improve PE diagnostic management in patients with AECOPD and thus, clinical care of patients with chronic obstructive pulmonary disease will certainly be improved with this work.