A giant left atrial myxoma causing mitral valve pseudostenosis – a mimicker

Abstract

The clinical features of cardiac myxoma vary significantly from asymptomatic to severe cardiovascular complications like atrioventricular valve obstruction and thromboembolism depending on the location, size, and mobility of the tumor. Echocardiography is the diagnostic study of choice, and surgical resection is the method of choice to prevent complications. We report a case of a 47-year-old female who presented with exertional dyspnea, malaise, and weight loss. Physical examination was significant for jugular venous distension, basal crackles in lungs, 2+ pedal edema, and rumbling diastolic murmur at apex. CT of the chest revealed a hypodense filling defect in the left atrium. Transthoracic echocardiogram showed a 5.5 × 4.5 cm mobile density, likely myxoma, attached to the interatrial septum and prolapsing into the left ventricle during the diastolic phase, causing functional mitral stenosis. She underwent a resection of cardiac myxoma. The histopathology report confirmed the diagnosis of myxoma, and post-operative recovery was uneventful.

A giant left atrial myxoma causing left-sided heart failure

“…9 Therefore, to prevent these life-threatening complications, early diagnosis and urgent excision of the tumor is considered essential. 2,3,7 This patient showed dyspnea (a symptom of left-sided heart failure) due to possible functional mitral stenosis caused by the giant atrial myxoma. Although the mass remained confined to the left atrium till the surgery, considering the tumor size and preoperative transthoracic echocardiography findings showing the tumor prolapsing into the left ventricle, the possibility of incarceration through the mitral valve was considered to be high, which could cause sudden death.…”

“…Therefore, to prevent these life-threatening complications, early diagnosis and urgent excision of the tumor is considered essential. 2 , 3 , 7 …”

“…5 Papillary character of the tumor may also lead to higher risk of embolism. 6 Abdelazeem et al 7 reported a case with severe obstructive complications due to functional mitral stenosis resulting in severe pulmonary hypertension and right-sided heart failure.…”

Mixoma cardiaco

“…Furthermore, females are at a higher risk for cardiac myxomas, with a female-to-male ratio 3:1. 3,7,8 The World Health Organization defines a cardiac myxoma as a neoplasm composed of stellate to plump, cytologically bland, mesenchymal cells set in a myxoid stroma. 9 The classic triad of cardiac myxoma are: 1) symptoms due to cardiac obstruction, 2) symptoms due to cerebral or peripheral embolism, and 3) constitutional symptoms.…”

“…The development begins in the interatrial septum of the fossa ovalis; 22% develops in the right atrium, 2% in the ventricles, and 1% in the valves, specifically attached to the anterior leaflet of the mitral valve. [3][4][5] The transthoracic echocardiogram is the first line of imaging for the diagnosis of myxoma. Magnetic resonance provides information on the location, size and characterization of the mass, in addition to helping the differential diagnosis with the presence of thrombus, essential data for the diagnosis approach and patient treatment.…”