The Efficacy and Safety of Intermittent Low-Dose Urokinase Thrombolysis for the Treatment of Senile Acute Intermediate-High-Risk Pulmonary Embolism: A Pilot Trial

Thrombolysis and anticoagulation were the main treatment methods for acute pulmonary embolism. However, the use of thrombolysis drugs may lead to bleeding complications. We compared intermittent low-dose urokinase (UK) and alteplase (recombinant tissue plasminogen activator [rt-PA]) in normotensive patients with intermediate-high-risk pulmonary embolism. The UK group was treated with intravenous UK 10 000 U/kg once a day for 7 days. The rt-PA group was given alteplase 50 mg by intravenous injection within 2 hours of admission. After thrombolytic therapy, 48 patients were included in this trial. Compared with before treatment, right and left ventricular diastolic diameter ratio, systolic pulmonary artery pressure, and cardiac troponin I of the 2 groups all significantly decreased 8 and 14 days after treatment, which indicated that right heart function improved. Total efficacy rates for the UK group 8 and 14 days after treatment (79.2%, 87.5%) and the rt-PA group (75.0%, 91.67%) were not significantly different. Adverse bleeding reactions were higher in the rt-PA group (20.8%) than in the UK group (8.3%). This pilot study indicates that intermittent low-dose UK thrombolysis is equally effective as rt-PA. However, future large-scale studies must also determine whether small doses of UK thrombolysis reduce the risk of bleeding.