Anticoagulation in Severe Heart Failure

A 10-year-old girl was transferred to our clinic with symptoms of progressive dyspnea, fatigue, and bilateral leg swelling. She had been diagnosed 3 years previously with idiopathic dilated cardiomyopathy (IDC). Her symptoms had worsened recently following short-term therapy with indomethacin for generalized musculoskeletal pain. On admission, the patient was in acute distress, diaphoretic, and pale. Her functional effort capacity was New York Heart Association (NYHA) class IV. Her blood pressure was 70/50 mm Hg, pulse rate 120 bpm, and body temperature 97.8°F. Chest and cardiac auscultation revealed bilateral diffuse crackles, audible S3, and a moderate pansystolic murmur over the mitral area radiating to the left axilla. A prominent shifting dullness and 4- to 5-cm hepatosplenomegaly were noted on abdominal examination. She had bilateral pretibial (+++) edema. The results of her coagulation work-up were negative, including normal levels of protein S, protein C, antithrombin III, and coagulation factor VIII. There was no factor V Leiden mutation. Transthoracic echocardiographic evaluation revealed severe biventricular hypokinesis with left ventricular ejection fraction of 15%, moderate to severe mitral and tricuspid regurgitation, and mild pericardial effusion (Figure, A and B). Her left and right heart chambers were dilated; pulmonary artery systolic pressure was measured at 65 mm Hg. She was prescribed furosemide, spironolactone, digoxin, enalapril, and low-dose aspirin. She received intermittent inotropes intravenously. Transthoracic echocardiography in the parasternal and short axis view on admission (A and B) and after 1 week of standard heart failure therapy without anticoagulation (C and D). The clinical scenario was better within a week; her symptoms were alleviated and her functional capacity improved to NYHA class II. However, her repeat echocardiographic examination revealed a left ventricular thrombus attached to the interventricular septum (Figure, C and D). Anticoagulation therapy was started immediately with deltaparin and coumadin. The patient was enrolled onto the cardiac transplantation list, but she died suddenly as a result of a major embolic event the following week. The overall outcome in children with IDC is poor. In the pediatric age group, the 5-year survival rate is about 60% to 70%.1,2 Thromboembolic event rates increase significantly in patients with IDC because of blood stasis in dilated hypokinetic cardiac chambers and increased procoagulant activity.3 Falk and colleagues4 have demonstrated the presence of a left ventricular thrombus to be as high as 44% on initial echocardiographic examination among patients with IDC. However, in children with IDC, intracavitary thrombus formation occurs less frequently, at a rate varying from 13% to 23%.2,5–7 Patients with left ventricular thrombi have been found to have a lower ejection fraction in comparison to patients without left ventricular thrombi, although the difference is not statistically significant; and the morphology of the left ventricular thrombi in children with systemic embolization showed nonprotruding features.6 Currently, oral anticoagulation is recommended for patients with IDC and a history of embolic events and/or atrial fibrillation.8,9 As left ventricular thrombus formation has not been found to be an independent predictor of an adverse outcome, routine anticoagulation of pediatric patients with dilated cardiomyopathy is not currently recommended.1,2,6 The use of warfarin for primary prevention of embolic stroke in patients with IDC and sinus rhythm is still controversial. The outcome in this case favors the early use of anticoagulation therapy in the pediatric group of patients.