Abstract

The correlation between intracavitary thrombosis detected by cross sectional echocardiography and systemic embolism was studied in 126 consecutive patients with idiopathic dilated cardiomyopathy who were examined from January 1980 to September 1987. A total of 1041 serial echocardiograms were obtained with 3.5 and 5 MHz transducers. The mean follow up period was 41.2 months. The survival rate was 88% at two years and 56% at five years. Echocardiography showed intracavitary thrombi in 14 (11.1%) patients; 13 were mural and 11 were localised at the apex of the left ventricle. Twelve patients (8.4%) had systemic emboli; this corresponded to an incidence of new embolic events of 1.4 for 100 patient-years. Patients with intracavitary thrombi or systemic emboli were treated with oral anticoagulants, as were nine in functional class IV of the New York Heart Association, for 61 patient-years. The cumulative observation period for the whole population study was 418 patient-years. None of the patients with intracavitary thrombosis had embolic complications and none of those with embolism had intracavitary thrombi. Rates of intracavitary thrombosis and systemic embolism in this series were low and there was no overlap between the two events. This may have been because the patients did not have severe dilated cardiomyopathy, because echocardiography did not detect all the thrombi, or because patients were treated with oral anticoagulants. The presence of intracardiac thrombosis detected by cross sectional echocardiography is not predictive of systemic embolism in patients with idiopathic dilated cardiomyopathy. Criteria for the use of the anticoagulant treatment remain largely empirical in these cases.