A Case Report of Severe Myocardial Stunning and Death Following Electro-Cardioversion (ECV) for Atrial Flutter

Electro-cardioversion (ECV) is considered a safe and effective therapy to terminate atrial arrhythmias. A 72-year-old previously well man with a history of hypertension and stroke with no residual deficits, presented with 1-day history of palpitations. ECG showed incomplete RBBB, atrial flutter with rapid ventricular rate and no ischaemic changes. There was no acute reversible precipitant identified and cardiac enzymes were normal. Initial transthoracic echocardiogram (TTE) showed normal biventricular size and function, satisfactory valvular function and moderate LA dilatation. He was commenced on apixaban and sotalol 80 mg bd. He underwent transoesophageal echocardiogram (TOE) and inpatient ECV. Initial TOE revealed no LV thrombus and confirmed previous TTE findings. He was cardioverted with 100 J direct current biphasic shock but developed prolonged asystole necessitating intubation and resuscitation. TTE imaging revealed severe biventricular dysfunction consistent with myocardial stunning. He required adrenaline boluses and was transferred to ICU in sinus rhythm on an infusion. During NG tube insertion 2 hours later, he developed bradycardia and then asystole. Temporary pacing wire was inserted with capture but no output. He failed to achieve return of spontaneous circulation and resuscitation was ceased. Post-mortem could not confirm the cause of death, but excluded oesophageal injury or acute myocardial infarction. Contributors to his acute cardiomyopathy may include stunning from his ECV or from resuscitation. This is an unfortunate case of severe biventricular dysfunction following ECV in prior structurally normal heart that resulted in death.