P4657Cardiac myxomas: are we dealing with distinct clinical entities?

Abstract Background Cardiac myxomas are rare, despite being the most common primary cardiac tumours. A significant number of myxomas are discovered accidentally in asymptomatic patients (pts), as there is increased use of non-invasive cardiac imaging. Our aim was to describe the experience of a cardiac surgery centre managing cardiac myxomas during the last 28 years. Methods Single-center retrospective study of consecutive pts admitted with the diagnosis of a cardiac myxomas between 1990 and 2018. Registry data concerning clinical presentation, non-invasive imaging assessment and definitive histopathology were collected. Results From 154 pts with the diagnosis of cardiac tumours, we identified 106 (68.8%) myxomas (67% females; mean age at diagnosis 61,5±13,1 years). Myxoma diagnosis increased throughout the 3 decades (27 cases until 2000; 26 cases in the second decade; 52 cases from 2010 until present). 30% of the pts were asymptomatic at diagnosis. Obstructive symptoms (heart failure and syncope) and embolic events were the most common complaints among symptomatic pts. Transthoracic echocardiography firstly identified the tumours in 88% of the cases. Cardiac magnetic resonance and computed tomography were performed for further investigation in 7% of the cases. Presumptive pre-operative diagnosis was correct in 83.8% pts. Surgical excision was successfully achieved in all cases. 89% of the tumours were located in the left atrium with inter-atrial septum implantation (13 in right chambers; 1 valvular tumour). There were 10 multifocal tumours. At histopathology myxomas were grossly described as mucous jelly appearance (80%), solid (15%) and mixed type lesions (5%). Rare histologic findings were described in 30% of the cases (8 tumours with bone tissue; 1 with forming bone marrow; 4 with endocrine type glandular epithelium; 16 with lympho-plasmocytic infiltrates; 3 with high mitotic grade; 5 with concomitant thrombus). For a median follow up of 86 [31–214] months there were 15 deaths (2 of them with tumour related deaths). There were 3 recurrences (2 with high mitotic grade histology), mostly occurring 3 years after the first intervention. Conclusion In this case series cardiac myxomas are the most common cardiac tumours, with a significant proportion of asymptomatic lesions. Clinical heterogeneity followed polymorphic histology, with recognized differences when compared to classical descriptions of this kind of tumour.