Long-term benefit of thrombolytic therapy in patients with pulmonary embolism

A total of 23 of the 40 patients who had angiographically proven pulmonary embolism and who had initially been randomized to an IV infusion of heparin (n = 11) or a thrombolytic agent (urokinase or streptokinase, n = 12) were restudied after a mean follow-up of 7.4 years to measure the right-sided p ressures and to evaluate their response to exercise during supine bicycle e rgometry. Results showed that, at rest, the pulmonary artery (PA) mean pres sure and the pulmonary vascular resistance (PVR) were significantly higher in the heparin group compared with the thrombolytic group (22 vs. 17 mmHg, p < 0.05, and 351 vs. 171 dynes s(-1) cm(-5), p < 0.02, respectively). Duri ng exercise both parameters rose to a significantly higher level in the hep arin group (from rest to exercise, PA: 22-32 mmHg, p < 0.01; PVR: 351-437 d ynes s(-1) cm(-5), p < 0.01, respectively), but not in the thrombolytic gro up (rest to exercise, PA: 17-19 mmHg, p = NS; PVR: 171-179 dynes s(-1) cm(- 5), p = NS). It is concluded that thrombolytic therapy preserves the normal hemodynamic response to exercise in the long term and may prevent recurren ces of venous thromboembolism and the development of pulmonary hypertension .