Safety and efficacy of ultrasound-accelerated catheter-directed lytic therapy in acute pulmonary embolism with and without hemodynamic instability

Objective: The objective of this study was to evaluate the safety and effectiveness of ultrasound-accelerated thrombolysis in acute pulmonary embolism.

Methods: A retrospective study of 45 patients was performed to evaluate treatment of acute pulmonary embolism at a single center from January 2011 to December 2013. All patients were diagnosed with computed tomography or ventilation-perfusion scan and had hemodynamic instability (systolic blood pressure <100 mm Hg) or right-sided heart strain evidenced by right ventricular dilation, septal deviation, or hypokinesis by echocardiography or computed tomography. EkoSonic catheters (EKOS Corporation, Bothell, Wash) were placed into the affected pulmonary arteries, and recombinant tissue plasminogen activator was infused through the catheters at 0.5 to 1.0 mg/h per catheter.

Results: Hypotension (systolic blood pressure <100 mm Hg) was present in 12 patients, with 100% resolution by treatment completion. Tachycardia (heart rate >100 beats/minute) was present in 26 patients and resolved in 92% by treatment completion; the average heart rate for all patients decreased from 109 to 77 beats/minute during the treatment period. Direct pulmonary artery pressure measurement showed average decrease of 21.5 mm Hg, representing a 40.2% reduction. Postprocedure echocardiography demonstrated complete resolution of cardiac dysfunction in 64%. Patients received a total dose of 30.5 mg (range, 14-66 mg) recombinant tissue plasminogen activator during an infusion time of 14.2 hours (range, 8-21 hours). There were no deaths through 90 days of follow-up and no major periprocedural bleeding events.

Conclusions: This retrospective study demonstrates the safety and efficacy of current ultrasound-accelerated thrombolysis methods to treat acute pulmonary embolism.