Literature has shown the efficacy of combination therapy when contraindications for use are adequately followed.19, 23, 26With a short half-life and studied safety, heparin is a frequently used anticoagulant in the pediatric population.37, 38Utilizing UFH does require intravenous access and frequent blood samples to monitor therapeutic drug levels.39Additionally, there is a risk of drug-induced thrombocytopenia.38In our patient, UFH was started once the initial cardiac thrombus was identified and was reduced to 10 U/kg/h during the 2 days r-tPA was administered. The gene discussed is PLAT; the disease is Thrombocytopenia.