This study investigates the distinct cellular composition of cardiac myxoma (CM), the pathways underlying its origin, and the mechanisms driving the development of diverse tumor morphologies. A comprehensive single-cell RNA sequencing (scRNA-seq) analysis was performed on five CM tissue samples and five normal atrial septum samples, encompassing the construction of a CM cell atlas, cell differentiation trajectory reconstruction, cell-cell interaction prediction, identification of cluster-specific transcription factor regulons, and assessment of tumor cell heterogeneity. Validation of scRNA-seq results was conducted through hematoxylin-eosin staining, multiplex immunofluorescence, cellular experiments, and a public database. This study profiled a total of 86,741 cells and identified 13 distinct cell sub-populations based on gene expression. Mesenchymal cells predominated in CM tissues, with high expression of calretinin. Findings from scRNA-seq analysis demonstrated that cardiac endothelial cells undergo endothelial-to-mesenchymal transition (EndoMT), giving rise to mesenchymal-like CM cells. Moreover, hematoxylin-eosin staining and multiplex immunofluorescence revealed variations in the subtypes and functions of tumor-associated fibroblasts and mural cells across different CM morphologies (lobulated and villous). This study demonstrated that CM cells exhibit mesenchymal-like characteristics and their origin is linked to the EndoMT of cardiac endothelial cells. The subtypes of tumor-associated fibroblasts and mural cells contribute to the morphological diversity of CM.

Intrathoracic migration of breast prostheses has been described after both open and minimally invasive cardiothoracic and breast surgery, with several proposed mechanisms of migration. In this report, we describe an unusual presentation of intrathoracic migration of a breast prosthesis following remote minimally invasive cardiac surgery for atrial myxoma resection. Due to the rare but documented risk of intrathoracic breast prosthesis migration following minimally invasive cardiothoracic surgery, consideration should be given to strategies for mitigating this risk at the time of surgery.

Cardiac myxoma (CM) is the most common benign primary cardiac tumor and is usually curable with complete surgical excision. However, CM can cause systemic embolization, and delayed cerebral metastasis is extremely rare. A 54-year-old woman presented with progressive lower limb weakness and was diagnosed with multiple cerebral infarctions associated with a left atrial pedunculated tumor. The tumor was completely resected under cardiopulmonary bypass and confirmed histopathologically as CM. Seven months later, she developed transient visual disturbances and right-hand weakness. Brain magnetic resonance imaging revealed enlarging lesions inconsistent with vascular territories. Craniotomy and histopathology with calretinin positivity confirmed metastatic myxoma. She underwent stereotactic radiotherapy and remained recurrence-free at 1 year. Even after complete resection of CM, delayed cerebral metastasis may occur. Persistent neurological surveillance and multidisciplinary management are essential for early detection and favorable long-term outcomes in patients with CM.

Primary cardiac tumours are rare, with cardiac myxomas representing the most common benign subtype in adults. Despite their benign histology, atrial myxomas may lead to significant clinical manifestations, including arrhythmias and heart failure. Giant left atrial myxomas are particularly uncommon, and their clinical presentation may vary depending on size, location, and associated haemodynamic effects.

Background Primary cardiac tumors are uncommon, with an incidence rate ranging from 0.001‰ to 0.3‰. Among cardiac tumors, 75% are benign and 25% are malignant. Approximately 50% of benign cardiac tumors are myxomas, while 75% of malignant cardiac tumors are sarcomas. Compared with myxomas, malignant cardiac tumors have a poorer prognosis. Cardiac myxosarcomas often have an insidious onset in young and middle-aged patients, with an overall survival period of 6 to 12 months. Similar to soft tissue tumors, cardiac sarcomas also consist of a range of histological subtypes. Among these, cardiac myxosarcomas are extremely rare, with only a few case reports documented in domestic and international literature to date. Due to similarities in imaging findings, they are often diagnosed as myxomas preoperatively, which may lead to insufficient resection during surgery. Owing to similarities in gross and histological features, coupled with the rarity of such cases, a small number of cases are misdiagnosed as myxomas in postoperative pathological examinations, and a definitive diagnosis is only made upon recurrence. This paper reports a case of a 23-year-old male patient with congenital heart disease and atrial septal defect, who had a history of interventional occlusion for atrial septal defect 12 years ago. The patient was admitted to the hospital for a rare giant myxosarcoma involving both atria, manifesting as rapidly progressive hemodynamic compromise. He underwent surgical resection of the cardiac tumor, and the pathological diagnosis was cardiac myxosarcoma. The tumor demonstrated highly malignant biological behavior. Rapid postoperative recurrence occurred, resulting in a short survival period. The patient eventually died of vena cava obstruction, heart failure and multiple organ failure secondary to tumor recurrence.

Myxomas are considered the most common among primary tumors. But right atrial myxomas are relatively rare.[1] A 49 year old male presented with left upper and lower limb hemiparesis which recovered spontaneously without residual weakness within 24 h without thrombolysis. A known diabetic and hypertensive, he was thoroughly evaluated which revealed a multifocal right atrial myxoma attached to the right atrial free wall and extending into the superior venacava. Serum anti-cardiolipin antibody IgG was positive. The myxoma was promptly excised under general anaesthesia. Cardiopulmonary bypass was instituted with cannulation of the aorta, right femoral vein draining the inferior venacava (IVC) and high superior venacava (SVC) under transesophageal echocardiography guidance. The sieve like infiltrations into the SVC were excised by briefly decannulating the SVC followed by immediate recannulation. Myocardial protection was ensured with pulmonary artery venting, del Nido cardioplegia, sterile topical ice saline and terminal warm reperfusion. The patent foramen ovale was directly closed with prolene sutures. Right atrial myxomas are known to be associated with antiphospholipid antibody syndrome, thus making it mandatory to be ruled out.[2] Right atrial myxomas are rare and those associated with patent foramen ovale are a further rarity.[4] Our approach to the excision of the myxoma has been unique since the inferior venacava was drained with right femoral vein cannulation to prevent disrupting the mass and further embolism, pulmonary artery venting was done instead of left atrial venting to prevent manipulation of the mass during right atrial retraction and the resection of the mass infiltrating into the SVC wall was done carefully by briefly decannulating the SVC and immediately recannulating post resection.

Fibrin-associated large B-cell lymphoma is an extremely rare subtype of LBCL, characterized by distinctive pathological findings and symptoms, and is generally considered to follow an indolent clinical course. Here we report a case of fibrin-associated large B-cell lymphoma arising in association with an incidentally discovered left atrial myxoma, which has remained in remission with surgical resection alone. The patient was an 84-year-old woman. In September 2023, a routine preoperative chest X-ray performed prior to surgery for osteoarthritis of the shoulder revealed an abnormal shadow. Subsequent echocardiography demonstrated an intracardiac mass in the left atrium, and the patient was referred to our cardiology department. Echocardiography at our hospital revealed a pedunculated mass attached to the atrial septum, consistent with a diagnosis of left atrial myxoma. The mass measured approximately 80 mm and prolapsed between the left atrium and ventricle. Given the risk of obstruction, urgent surgical resection was performed. Histopathological examination of the resected specimen confirmed the diagnosis of fibrin-associated large B-cell lymphoma, and the patient was subsequently referred to the hematology department. A systemic workup revealed no evidence of additional disease. She has remained disease-free without any further therapy.