Central versus peripheral pulmonary embolism: Analysis of the impact on the physiological parameters and long-term survival

BACKGROUND: Studies aimed at assessing whether the emboli lodged in the central pulmonary arteries carry a worse prognosis than more peripheral emboli have yielded controversial results. AIMS: To explore the impact on survival and long-term prognosis of central pulmonary embolism. PATIENTS AND METHODS: Consecutive patients diagnosed with acute symptomatic pulmonary embolism by means of computed tomography (CT) angiography were evaluated at episode index and traced through the computed system of clinical recording and following-up. Central pulmonary embolism was diagnosed when thrombi were seen in the trunk or in the main pulmonary arteries and peripheral pulmonary embolism when segmental or subsegmental arteries were affected. RESULTS: A total of 530 consecutive patients diagnosed with pulmonary embolism were evaluated; 255 patients had central pulmonary embolism and 275 patients had segmental or subsegmental pulmonary embolism. Patients with central pulmonary embolism were older, had higher plasma levels of N-terminal of the prohormone brain natriuretic peptide (NT-ProBNP), troponin I, D-dimer, alveolar-arterial gradient, and shock index (P < .001 for each one). Patients with central pulmonary embolism had an all-cause mortality of 40% while patients with segmental or subsegmental pulmonary embolism (PE) had an overall mortality of 27% and odds ratio of 1.81 confidence interval (CI) 95% 1.16-1.9. Survival was lower in patients with central PE than in patients with segmental or subsegmental pulmonary embolism, even after avoiding confounders (P = .018). CONCLUSIONS: Apart from a greater impact on hemodynamics, gas exchange, and right ventricular dysfunction, central pulmonary embolism associates a shorter survival and an increased long-term mortality.