THE COAGULATION SYSTEM IS ACTIVATED IN IDIOPATHIC CARDIOMYOPATHY

Objectives. We investigated the plasma levels of molecular markers for platelet activity and the thrombotic and fibrinolytic status in patie nts with hypertrophic cardiomyopathy and dilated cardiomyopathy to det ermine the activating site of coagulation in these disorders. Backgrou nd. A thromboembolic event is a serious complication in patients with idiopathic cardiomyopathy. However, the activating site of the coagula tion system in idiopathic cardiomyopathy has not been fully investigat ed. Methods. We determined the plasma levels of molecular markers for platelet activity (platelet factor 4 and beta-thromboglobulin), thromb otic status (fibrinopeptide A and thrombin-antithrombin III complex) a nd fibrinolytic status (D-dimer and plasmin-alpha(2)-plasmin inhibitor complex) in 13 patients with hypertrophic cardiomyopathy, 17 patients with dilated cardiomyopathy and 20 normal subjects. Results. Plasma l evels of platelet factor 4, beta-thromboglobulin and plasmin-alpha(2)- plasmin inhibitor complex did not differ significantly among the three groups, whereas plasma levels of fibrinopeptide A and thrombin-antith rombin III complex in both patient groups were significantly higher th an those in normal subjects. Plasma levels of D-dimer in patients with dilated cardiomyopathy were significantly higher than those in patien ts with hypertrophic cardiomyopathy and normal groups. In patients wit h hypertrophic cardiomyopathy, both fibrinopeptide A and thrombin-anti thrombin III complex levels were significantly correlated with left at rial diameter. In patients with dilated cardiomyopathy, fibrinopeptide A and thrombin-antithrombin III complex levels showed a positive corr elation with left ventricular end diastolic volume and a negative corr elation with fractional shortening of the left ventricle. Conclusions. The activated coagulation system in patients with hypertrophic and di lated cardiomyopathy mag be triggered by left atrial dilation in hyper trophic cardiomyopathy and left ventricular enlargement and dysfunctio n in dilated cardiomyopathy.