Thrombolytic therapy of prosthetic valve thrombosis with recombinant tissue plasminogen activator (rt-PA) in infancy and childhood

Thrombotic obstruction of a mechanical cardiac valve prosthesis requires urgent therapy. We report on the treatment of prosthetic valve thrombosis with recombinant tissue plasminogen activator (rt-PA) in three children at the age of 4, 10 and 18 months, in whom a St. Jude Medical prosthesis had been placed at the atrioventricular valve level 2 to 6 weeks earlier. The initial rt-PA dose was 0.4 mg/kg given over 15 min and followed by a continuous daily infusion of 1.6 to 2.0 mg/kg. In addition the patients received heparin (200 U/kg/d). Thrombolytic therapy was administered for a range of 4 to 28 days. The therapy was successful in the first case. The second child had four recurrent events of prosthetic valve thrombosis and the thrombolytic therapy was successful three times. However, the prosthesis had to be finally replaced. In the third case the thrombolytic therapy was only partially successful due to an organized thrombus requiring prosthesis replacement.