Clinical course and prognosis of acute pulmonary embolism

Summary

 Effective treatment of acute pulmonary embolism (PE) requires prompt identification of patients at high risk of death or severe cardiovascular complications during the hospital stay. Determination of prognostic parameters in this heterogeneous patient population is far more important than calculation of a crude mortality rate due to PE. The multicenter Management Strategy and Prognosis in Pulmonary Embolism Registry examined the in-hospital clinical course of 1001 consecutive patients with acute PE. Overall mortality was 22%, with 91% of deaths directly related to PE. Clinical signs of acute right heart failure due to major PE (arterial hypotension, shock, circulatory collapse) were clearly associated with an adverse outcome. Mortality ranged from 8 to 65% depending on the severity of clinical instability at presentation. Importantly, a significantly increased death rate was also observed in patients with echocardiographically detected right ventricular dilation (84 vs. 16%), a reliable noninvasive index of impending right heart failure. The independent prognostic effect of this finding was confirmed by multivariate analysis (Odds Ratio, 2.44; P=0.004). Thus, the combination of clinical and echocardiographic findings permits accurate risk stratification of patients with acute PE. Evidence is also accumulating that these prognostic factors can be used to identify candidates for early thombolytic treatment.