Cardiac Amorphous Tumour (CAT) Presenting with Thrombocytopenia

Cardiac calcified amorphous tumour (CAT) is a rare non-neoplastic lesion with only a few cases reported in literature. We present an interesting case of CAT that was associated with unexpectedly low platelet count. A 40-year man presented with shortness of breath on exertion. Echocardiogram showed a mobile mass within the right atrium. Mass was surgically excised. His platelet count varied from 26,000/ul to 54,000/ul before surgery, which increased postoperatively. Histopathological examination revealed amorphous mass of eosinophilic fibrin with dense calcification. No morphologic evidence of myxoma was seen and the final diagnosis of CAT of the heart was rendered. CAT is a rare cardiac lesion with an excellent prognosis after complete surgical removal. The microscopic examination is the only tool for definitive diagnosis.