Abstract
Primary cardiac tumors are infrequently encountered, with a higher prevalence of secondary tumors. Among primary cardiac tumors, myxomas are benign and more commonly observed, while angiosarcomas constitute the most frequently encountered malignant tumors. Intimal sarcomas, the least prevalent among primary cardiac tumors, are seldom reported. This case report details the unique instance of a patient diagnosed with spindle cell neoplasm, a type of intimal sarcoma mimicking atrial myxoma with distant metastases, manifesting complications such as new onset atrial fibrillation and heart failure. A male in his 70s, presented with subacute Dyspnea on minimal exertion, orthopnea, paroxysmal nocturnal dyspnea. Initial investigations, revealed new onset AFIB, heart failure with cardiomegaly and atrial masses suggestive of thrombi. Echocardiograpgy findings was consistent with atrial myxoma. Subsequent PET scan indicated malignancy with metastases to the spine. The patient opted for chemotherapy and palliative resection, which was incomplete with positive margins. Tumor biopsy revealed intimal sarcoma (spindle cell neoplasm) which was sensitive to Capmatinib and Pikray. Patient expired nine months later