Inhospital mortality of patients with submassive pulmonary embolism submitted to thrombolytic therapy in a multicenter study

Purpose

Thrombolytic therapy for submassive pulmonary embolism (SPE) remains controversial due to the lack of evidence for mortality reduction. We compared inhospital mortality of SPE patients submitted to r-TPA, unfractioned heparin (UFH) or low-weight molecular heparin (LWMH) in a prospective multicenter study.

Methods

A multicenter cohort included 625 patients, from January 1998 to May 2003, admitted with diagnosis of pulmonary embolism confirmed by: pulmonary angiography, helical computer tomography, magnetic resonance, echocardiography or lung scan. One hundred and thirty-three patients (49% males, 68 ± 15 years old) were considered having SPE after associated acute right ventricular dysfunction on a 2D echocardiogram and an absence of arterial hypotension. Syncope and chronic cor pulmonale were the exclusion criteria. Therapy (r-TPA, UFH or LWMH) was initiated after diagnosis, at the physician's discretion.

Results

Overall inhospital mortality was 15.4%. Fifty eight patients received UFH, 35 patients had LWMH and 40 patients had r-TPA. The inhospital mortality was 19.3%, 17.6% and 10.8%, respectively (P = 0.54). In univariate analysis, a lower mortality was observed among patients with heart failure submitted to r-TPA (P = 0.008), which was non-significant in multivariate analysis (P = 0.75). There was no difference when comparing LMWH versus r-TPA (P = 0.4) and UFH versus r-TPA (P = 0.27).

Conclusion

In this non-selected SPE population, no significant difference was found among patients submitted to thrombolytic therapy when compared with heparin for inhospital mortality.