Thrombolytic therapy in the treatment of acute sub-massive pulmonary embolism: a prospective observational study.

The use of thrombolytic therapy in haemodynamically stable patients with sub-massive pulmonary embolism is still controversial. We conducted this study to observe the safety and efficacy of thrombolytic therapy in acute pulmonary embolism patients with normal blood pressure in a tertiary cardiac centre. In this study, 130 patients with sub-massive pulmonary embolism who had right-ventricular dysfunction were included and treated with thrombolytic therapy. Forty-one percent of patients in our study were within 40 years of age. Eighty-three percent of patients had clinical improvement. Both right-ventricular dysfunction and pulmonary artery systolic pressure were improved significantly following thrombolytic therapy from baseline (49 vs. 28 mmHg; P = 0.01; 95% confidence interval -13 to -56). Only 9% patients had died and two patients had intra-cerebral haemorrhage during this study. Thrombolytic therapy may be helpful in improving clinical course following sub-massive acute pulmonary embolism, especially for those who had low risk of bleeding. Further randomized study with large sample size is needed for final conclusion.