Patients with cardiac tumours may present with cardiovascular related or constitutional symptoms, but more often cardiac mass is discovered incidentally during an imaging examination performed for another indication. Around 90% of primary cardiac tumours at surgery are benign, with approximately 80% representing myxomas1. Myxomas are usually solitary. 75% arise in the left atrium and 15-20% in the right atrium.
These characteristically arise from or near the interatrial septum at the border of the fossa ovalis3. They occur in all age groups, most frequently between the third and sixth decade with a predilection for the female gender. It may vary from 1-15 cm in diameter.
These are usually polypoid with a smooth or gently lobulated surface, often pedunculated, and characteristically arise from a narrow stalk. Polypoid myxomas are compact and rarely embolise. However, the less common villous or papillary myxomas have fragile villous extensions which tend to embolise.
Sarcomas can also present as a left atrial mass and may be mistaken for a myxoma preoperatively2. In particular, angiosarcomas tend to arise in the right atrium. Rhabdomyomas and fibromas usually arise in the ventricles. Papillary fibroelastomas on the other hand involve cardiac valves. CASE PRESENTATION A 40 year-old-male a farmer by occupation was admitted with complaints of one episode of syncope 3 years back, exertional dyspnoea from 17 months. His dyspnoea occurred mostly while he lies on bed, but was not relieved by sitting upright. It also occasionally aggravated by exertion.
Our patient also complained of low grade fever, malaise and headache for 10 months. The fever was irregular in nature and was not associated with cough or hemoptysis.. He had no history of asthma or tuberculosis. He had no known history of congestive heart failure,liver disease, raynauds phenomenon, paroxymal nocturnal dyspnea,endocrine disorders, or chest pain. Physical examination revealed a pulse rate of 80 bpm, blood pressure of 94/60 mm Hg.
Jugular venous distension of 5 cm was noted. Cardiac examination revealed a soft S1 and a diastolic rumbling murmur heard in the left lower sternal border. INVESTIGATIONS Initial laboratory investigations revealed a erythrocyte sedimentation rate of 58 mm at 1 hour ( males 2-22 mm at 1 hour ), CRP of 6.9 mg/dl (normal value < 6 mg/dl).
Blood urea was 90 mg/dl and serum Creatinine was 4.5 mg/dl. Cardiac CT was planned but due to renal dysfunction was deferred. Renal dysfunction was managed medically.
ECG revealed right atrial enlargement and right bundle branch block. The chest x-ray was normal. A transthoracic echocardiogram was performed on the patient in recumbent position. A large right atrial mass was present. This mass prolapsed through the tricuspid orifice resulting in haemodynamic obstruction across tricuspid valve with a mean diastolic transtricupid gradient of 12 mm Hg. The mass was seen attached at the junction of right atrium and inferior vena cava extending from RA to RV with right atrial, right ventricular and IVC dilation (Figure 1-4) (Videos1-4). After providing written informed consent, our patient underwent median sternotomy under general anesthesia.
Cardiopulmonary bypass (CPB) was established with conventional mild hypothermia (34.0°C). Per-operative findings and procedures were- A 10 x 5.
0 x 5.0 cm encapsulated mass (Fig. 5&6), occupying right atrium (RA) and right ventricle (RV). It was attached to the junction of inferior vena cava and right atrium by a narrow stalk.
The tumor was seen in both the atrium and ventricle during systole and diastole causing obstruction to the right ventricular inflow tract. Careful removal of the mass was done to avoid pulmonary embolism with adequate tissue surrounding the stalk. RA & RV cavity was washed with normal saline. The resected mass was sent for histopathological examination.CPB was discontinued without any complications and the patient remained stable hemodynamically. Our patient was shifted to intensive care unit and was subsequently discharged on fifth postoperative day from the ward.
Macroscopically, the tumor presented as a 10 × 5.0 × 5.0 cm lobulated greyish mass weighing 100 g and had an irregular surface and polypoid areas of elastic consistency and spots of loose and friable tissue . Histologically, the predominant cell type was round, stellate and polygonal cells arranged in sheets and in singles surrounded by abundant loose myxoid stroma.
The cells showed minimum pleomorphism and occasional mitotic figure were seen. Also seen were many vascular channels lined with flat endothelial cells. Findings were suggestive of myxoma.(Figure7).