Morin J E, Rahal D P, Hüttner I
Department of Cardiothoracic Surgery, McGill University Health Centre and Royal Victoria Hospital, Montreal, Canada.
Can J Cardiol. 2001 Mar;17(3):331-6.
Primary tumours of the heart are rare. The majority of these tumours are benign, with myxomas located in the left atrium being the most common form. Almost all malignant tumours are sarcomas and occur preferentially in the right side of the heart. An exception to this rule is leiomyosarcoma, a rare form of primary cardiac sarcoma that occurs predominantly in the left atrium, as does cardiac myxoma. The case of a 53-year-old woman who presented with symptoms of mitral valve stenosis and pulmonary hypertension is reported. Cardiac catheterization, angiography and echocardiography revealed a left atrial mass that was interpreted as atrial myxoma. At the time of operation, the myxoid appearance of the tumour mass further supported this assumption. The tumour, including a wide rim of atrial septum, was removed with cautery. Histopathological examination unexpectedly showed that the tumour was not an atrial myxoma but rather a myxoid variant of a primary leiomyosarcoma. Immunohistochemistry and electron microscopy confirmed the diagnosis. Local radiotherapy was considered but deemed contraindicated in view of the longstanding pulmonary hypertension. Two months after excision, a repeat echocardiogram indicated recurrence of tumour in the left atrium, and the patient died a few days later. The preferential left atrial location and the frequently myxoid appearance of primary leiomyosarcomas of the heart make it particularly difficult to differentiate them preoperatively from atrial myxomas. The authors recommend resection of all atrial myxoid tumours with a wide (at least 1 cm) margin, combined with intraoperative frozen section diagnosis, because complete surgical resection appears to correlate with prolonged survival in the few reported cases of atrial leiomyosarcomas. In cases of incomplete initial resection or local recurrence in the absence of metastatic disease, heart transplantation may be a valid option in appropriately selected patients.
心脏原发性肿瘤较为罕见。这些肿瘤大多数为良性，其中位于左心房的黏液瘤最为常见。几乎所有恶性肿瘤均为肉瘤，且多发生于心脏右侧。平滑肌肉瘤是此规律的一个例外，它是原发性心脏肉瘤的一种罕见形式，主要发生于左心房，与心脏黏液瘤的发病部位相同。本文报告了一名53岁女性患者，她出现二尖瓣狭窄和肺动脉高压症状。心脏导管检查、血管造影和超声心动图显示左心房有一肿块，初步诊断为心房黏液瘤。手术时，肿瘤肿块的黏液样外观进一步支持了这一诊断。连同宽的房间隔边缘一并用电灼法切除肿瘤。组织病理学检查意外发现该肿瘤并非心房黏液瘤，而是原发性平滑肌肉瘤的黏液样变体。免疫组织化学和电子显微镜检查证实了诊断。考虑过局部放疗，但鉴于长期存在的肺动脉高压，认为不适合采用。切除术后两个月，复查超声心动图显示左心房肿瘤复发，患者于数日后死亡。心脏原发性平滑肌肉瘤优先发生于左心房且外观常呈黏液样，这使得术前将其与心房黏液瘤区分开来尤为困难。作者建议对所有心房黏液样肿瘤进行至少1厘米宽切缘的切除，并结合术中冰冻切片诊断，因为在少数已报道的心房平滑肌肉瘤病例中，完整的手术切除似乎与延长生存期相关。在初始切除不完全或无转移疾病但局部复发的情况下，对于适当选择的患者，心脏移植可能是一种有效的选择。
