Catheter-directed thrombolysis for severe pulmonary embolism in pediatric patients

Background: Catheter-directed thrombolytic (CDT) therapies for severe pulmonary embolism (PE) have been shown to be effective and safe when compared with systemic thrombolysis in adults. Pediatric studies assessing efficacy and safety of CDT for PE are lacking. Hence, our aim was to review CDT as a therapy for pediatric PE.

Methods: We retrospectively reviewed charts of patients aged <18 years, who underwent CDT for main or major branch pulmonary artery occlusion associated with hypotension or right ventricular dysfunction secondary to PE during a 3-year period, in our tertiary care academic Pediatric Intensive Care Unit.

Results: Six CDT interventions were performed on 5 patients with PE (median age: 16.5 years). All patients presented with chest pain and dyspnea. The predisposing factors for thrombogenesis differed in all patients, and all had multiple risk factors. Five of six procedures (83%) were accompanied by ultrasound agitation with EKOS endowave infusion system (ultrasound-accelerated CDT [UCDT]), whereas 1 had CDT without ultrasound agitation. Complete resolution of PE occurred in 4 instances (67%) at 24 hr, whereas in 2 cases (33%), there was partial resolution. One patient with complete resolution underwent another successful UCDT after 4 months for recurrence. Clinical parameters (heart rate, respiratory rate, blood pressure, and oxygen saturations) and echocardiographic findings improved after treatment in all the patients. Median duration of hospital stay was 9 days with no mortality and treatment-related complications. All patients were discharged with long-term anticoagulation.

Conclusions: Our case series is the first that describes CDT/UCDT as an effective and safe therapy for pediatric patients with severe PE. CDT is known to accelerate fibrinolysis via focused delivery of thrombolytic agent to the thrombus site. For carefully selected patients, CDT/UCDT provides a useful treatment option for severe PE irrespective of the etiology, predisposing conditions, and associated comorbidities.