Recombinant Tissue Plasminogen Activator in the Treatment of Neonates with Intracardiac and Great Vessels Thrombosis.

Life-threatening intracardiac and great vessels thrombi are rare in neonates. Recombinant tissue plasminogen activator (rTPA) is used in adults to stimulate fibrinolysis and facilitate thrombus resolution. Its use in neonates, along with heparin, remains controversial because of potential risk of serious bleeding. We aim to present our experience with the use of thrombolytic agents in seven neonates and young infants. In a retrospective study, over a period of 6 years, the medical records of neonates and young infants, who were diagnosed with intracardiac and great vessels thrombi, were reviewed. The following factors were collected: demographic data, primary diagnosis, thrombus site, risk factors, method of diagnosis, thrombolytic and/or anticoagulation agent, route, dose and duration of treatment, complications, and outcome. Six neonates and one 45-day-old infant were analyzed. Age ranged from 5 to 45 days (median age 12 days), and median weight was 2.9 kg (range 0.9-3.8 kg). The thrombi were diagnosed by echocardiography in five and by angiography in two cases. All patients had life-threatening thrombi; four were treated with rTPA (0.5 mg kg(-1) h(-1)) and heparin infusions with complete dissolution of the thrombi, within a median time of 60 h (6-72 h), and without complications. The remaining three patients (two who were premature, at 28 and 34 weeks of gestation, and the third who had a deranged coagulation profile) were treated with unfractionated heparin due to fear of bleeding. The thrombi dissolved in the premature babies (within 2 weeks and 3 months, respectively) but embolized and resulted in the death of the third infant after 2 weeks of treatment. The current case series confirmed the effectiveness and safety of intravenous rTPA infusion, at the dosages used, in neonates and young infants with life-threatening thrombi.