What is the investigation of choice in an asymptomatic 27 year old lady with arrhythmias and a systolic murmur with midsystolic click?

The patient in the question with clinical signs of systolic murmur with mid-systolic click is likely to be sufferring from mitral valve prolapse. The ECG most commonly is normal, but may show biphasic or inveed T waves in leads II, III, and aVF. Trans-thoracic echocardiography (TTE) is effective in identifying the abnormal position and prolapse of the mitral valve leaflets. A useful echocardiographic definition of MVP is systolic displacement (in the parasternal long axis view) of the mitral valve leaflets by at least 2 mm into the LA superior to the plane of the mitral annulus. TTE is indicated when more accurate information is required and is performed routinely for intraoperative guidance for valve repair. Ref: Harrison's Internal Medicine, 18th Edition, Page 1937