A 52 year old man with hypertension was admitted with a history of sudden onset palpitations, light headedness, and breathlessness. On examination he was apyrexial with a blood pressure of 113/52 mm Hg and pulse rate 110 beats per minute. He had soft systolic and early diastolic murmurs with normal chest auscultation; there was no haemodynamic discrepancy between left and right sides or stigmata of …