A Pendulum in The Heart : Mitral Valve Myxoma Presenting as Recurrent Pre-syncope and Palpitations

Abstract

Cardiac myxomas are the most common histological type, accounting for 30–50% of all primary cardiac neoplasms, with an estimated clinical incidence of 0.5 per million population per year. We report a case of a 60-year-old woman with poorly controlled hypertension and type 2 diabetes who presented with several months of recurrent pre-syncopal episodes and palpitations. Clinical examination revealed sinus tachycardia at 120 bpm without an audible murmur — a deceptively unremarkable finding given the underlying pathology. Transthoracic echocardiography identified a mobile echogenic mass measuring 33 × 22 mm arising from the mitral valve, with Doppler evidence of intermittent inflow obstruction. Cardiac MRI confirmed the diagnosis of mitral valve myxoma. The patient underwent urgent surgical resection via median sternotomy with complete tumour excision and successful mitral valve preservation. Histopathology confirmed myxoma. At the twelve-month follow-up, she remained asymptomatic with no recurrence and preserved valve function. Primary cardiac tumours are rare (prevalence 0.001–0.03% in autopsy series), and myxomas arise from the mitral valve in fewer than 50 reported cases worldwide. This exceptional rarity, combined with a presentation dominated by pre-syncope and palpitations rather than the classic diastolic rumble expected with mitral obstruction, makes the diagnosis particularly elusive. The absence of an audible murmur reflects the intermittent and positional nature of tumour-related obstruction, which differs fundamentally from the fixed haemodynamic profile of rheumatic mitral stenosis. Early surgical referral with a valve-sparing approach, whenever feasible, is recommended to achieve optimal clinical outcomes while avoiding prosthetic valve-related complications. Long-term echocardiographic follow-up remains essential because of the potential for tumour recurrence.