[Intracardial thrombus formation in heparin-associated thrombocytopenia type II]

Deep vein thrombosis of the right leg occurred in a 77-year-old woman after percutaneous cardiac catheterization via the right femoral vein, performed to assess mitral valve disease with atrial fibrillation. She thereupon received intravenous heparin (1,000 IU/h; partial thromboplastin time 60-70s). 13 days later she developed a transient incomplete right brachiofacial hemiparesis with motor aphasia. Transthoracic echocardiography revealed a fresh left atrial thrombus. Platelet count fell from initially normal levels to 20 x 10(9)/l. Because type II heparin-associated thrombocytopenia was suspected heparin administration was discontinued and phenprocoumon administered. Heparin-dependent antibodies were demonstrated with the heparin-induced platelet activation test. Cross reactions occurred in vitro against all low-molecular heparins and heparinoid ORG 10172. The platelet count had become normal 17 days later, the leg veins had recanalized and the intraatrial thrombus had become much smaller. The patient declined cardiac surgery and was discharged on the 41st hospital day in satisfactory general condition on maintenance anticoagulant dosage.