BACKGROUND: The impact of central localization of pulmonary embolism (PE) on clinical outcomes is uncertain. OBJECTIVES: To compare clinical presentation, risk factors, and outcomes between patients with central pulmonary embolism (cPE) and non-cPE. METHODS: We retrospectively analyzed 597 patients with acute PE from the prospective SWITCO65+ cohort between 09/2009-12/2013. cPE was defined as an embolus in the pulmonary trunk or the left or right pulmonary artery. We compared baseline clinical characteristics and outcomes at 3 months (recurrent venous thromboembolism [VTE], overall/PE-related mortality, PE-related quality of life) and over the entire follow-up (recurrent VTE, overall/PE-related mortality) between patients with cPE vs. non-cPE. We examined the association between PE localization and recurrent VTE and overall mortality, adjusting for multiple confounders including thrombolysis and periods of anticoagulation, and competing risk of non-VTE-related death if appropriate. RESULTS: Overall, 217 (36.3%) patients had cPE. Symptoms/signs of respiratory distress, right-ventricular dysfunction, and myocardial injury were more prevalent in those with cPE. VTE recurrence, overall/PE-related mortality, and PE-related quality of life at 3 months did not vary by PE localization. After a median follow-up of 29.6 months, patients with cPE had a higher risk of fatal PE (5.5% vs. 2.1%
P=0.033). After adjustment, cPE was associated with recurrent VTE (SHR 2.22, 95%CI 1.25-3.91) but not with overall mortality (HR 0.74, 95%CI 0.45-1.21) during follow-up. CONCLUSION: cPE was associated with a 2.2-fold increased risk of recurrent VTE compared to non-cPE. Whether an extended anticoagulation duration could reduce the recurrence risk following cPE should be further examined.