Prevalence of pulmonary embolism among patients with recent onset of dyspnea on exertion. A cross-sectional study

Abstract

BackgroundExertional dyspnea is a frequently encountered complaint in clinical practice. However, the prevalence of pulmonary embolism (PE) among patients with dyspnea on exertion has not been reported. ObjectiveThe objective of this study was to assess the prevalence of objectively confirmed PE among consecutive patients visiting an emergency department because of recent onset of exertional dyspnea. MethodsPatients aged ≤75 years with recent (<1 month) marked exertional dyspnea had a systematic workup for PE, irrespective of concomitant signs or symptoms of venous thromboembolism and alternative explanations for dyspnea. PE was excluded on the basis of a low pretest clinical probability and normal age-adjusted D-dimer. All other patients had computed tomography pulmonary angiography. An interim analysis after inclusion of 400 patients would stop recruitment if the 95% confidence interval (CI) of the PE prevalence had a lower limit exceeding 20%. ResultsThe study was prematurely terminated after the inclusion of 417 patients. In 134 patients (32.1%), PE was excluded based on low clinical probability and normal D-dimer. PE was found in 134 (47.3%) of the remaining 283 patients, for an overall prevalence of 32.1% (95% CI, 27.8-36.8). PE was present in 40 of 204 (19.6%) patients without other findings suspicious for PE and in 94 of 213 patients (44.1%) with such findings. PE involved a main pulmonary artery in 37% and multiple lobes in 87% of the patients. ConclusionThe angiographic demonstration of PE is common in patients presenting with recent onset of marked exertional dyspnea, including 20% without other findings suggesting pulmonary embolism.