Low dose tissue plasminogen activator treatment for vascular thrombosis following cardiac catheterization in children: a single center experience.

OBJECTIVES: To assess the efficacy and safety of low dose tissue plasminogen activator (tPA) therapy in children with vascular thrombosis following cardiac catheterization. BACKGROUND: Currently, heparin is the standard of care for vascular thrombosis, however, it may not be efficacious in dissolving existing thrombi. Although tPA is an accepted thrombolytic therapy for life-threatening thrombosis in children, it is not a well-established treatment for the thrombosis of femoral vessels following cardiac catheterization. METHODS: A retrospective analysis was performed from 1/1/2009 until 6/30/2011 at Rady Children's Hospital-San Diego (RCHSD) reviewing all cases with venous or arterial thrombosis at the vascular access site following cardiac catheterization, and a survey was conducted among the Congenital Cardiovascular Interventional Study Consortium members regarding their experience in tPA therapy. RESULTS: At RCHSD, out of 1,155 catheterizations, 12 children developed femoral thrombosis. In three children, where 12-h heparin therapy was unsuccessful in resolving thrombosis, we used low-dose tPA according to the following regime: 0.05 mg/kg/h for 30 min, followed by 0.1 mg/kg/h for 4 h. We achieved thrombolysis in all cases evidenced by repeat ultrasound and return of palpable pulse with normal limb circulation. No complications were encountered. The survey confirmed that adult tPA dose (0.1-0.5 mg/kg/h) has 100% efficacy in resolving thrombi in children with vascular thrombosis, however, the rate of serious complications was not negligible (15%). CONCLUSION: tPA is an efficacious therapy to dissolve thrombi that developed as a complication of cardiac catheterization in children. The rate of complications due to tPA may be reduced using a lower dose: 0.05-0.1 mg/kg/h.