Local low-dose urokinase treatment of acquired intracardiac thrombi in preterm infants.

We report three cases of intracardiac thrombi in preterm infants of very low birth weight, in whom local low-dose urokinase treatment achieved complete thrombolysis without any signs of systemic fibrinolytic activity or side-effects. This new treatment strategy seems to be safe, requires minimal monitoring of fibrinolytic activity, and may be a new option for thrombolysis in high-risk patients such as premature infants, patients recently operated on, and patients presenting with other contra-indications for systemic fibrinolytic therapy.