Clinical introduction

A woman in her 30s, a case of rheumatic mitral stenosis status post balloon mitral valvuloplasty 15 years prior, presented to urgent care with palpitations and dyspnoea for 1 week. She was noted to be in heart failure, with hypotension and tachycardia. Initial assessment with electrocardiography revealed a regular narrow complex tachycardia with 2:1 atrioventricular (AV) relationship, no clear isoelectric baseline and positive P waves in lead V1 consistent with an atrial flutter of left atrial origin with a rapid ventricular rate (~160/min) (figure 1A). Echocardiography demonstrated severe calcific mitral stenosis with pulmonary hypertension. With decompensated heart failure and adequate prior anticoagulation, the patient underwent direct current synchronised cardioversion for her arrhythmia. She reverted to normal …