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Left atrial myxoma: an unusual cause of pre-syncope and symptomatic bradycardia
Kenny Vongbunyong1, Steven Sinfield2, Ned Premyodhin3
1Department of Medicine, University of California, Irvine, 333 The City Blvd. West, Suite 400, Orange, CA, 92868, USA. kvongbun@hs.uci.edu.
Background:
Atrial myxomas account for approximately 50% of all primary cardiac tumors. The size, location, risk of embolic event, and involvement of other cardiac structures, are all factors that contribute to the wide range of presentation for cardiac myxomas. Patients with myxomas may remain asymptomatic, while others may report symptoms such as fatigue and fever, dyspnea, and syncope. It is important to recognize arrhythmias as an uncommon symptom of myxomas.
Case Presentation:
We report a rare case of a 67-year-old man who presented with pre-syncopal episodes, symptomatic bradycardia, and night sweats found to have a 5.5 × 5.1 × 3 cm myxoma in the left atrium. During diastole the mass caused dynamic flow obstruction across the mitral valve. The patient underwent surgical resection of the mass given his symptomatology and risk of embolic events. Removal of the myxoma resulted in resolution of both pre-syncopal episodes and the patient's sinus bradycardia.
Conclusion:
Atrial myxomas are a rare cause of pre-syncope and symptomatic bradycardia. It is important to have a clinical suspicion for atrial myxomas given early diagnosis and surgical intervention are key in improving the prognosis of these patients. This case also highlights the importance of taking into account the source of the myxoma's blood supply in relationship to other cardiac structures, and further correlating these findings with clinical symptoms.
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