A case of ventricular asystole without escape rhythm 4 days after percutaneous transluminal septal myocardial ablation in hypertrophic obstructive cardiomyopathy with drug-resistant paroxysmal atrial fibrillation

Abstract

A 42-year-old man with a more than 10-year history of hypertrophic obstructive cardiomyopathy, but no history of heart failure or syncope, had left ventricular outflow tract pressure gradient (LVOT-PG) of 50-80mmHg on Doppler echocardiography. In June 2010, he experienced general malaise on effort, and LVOT-PG increased to 124mmHg. Two months later, he suffered a transient ischemic attack, complicated with atrial fibrillation (AF). He underwent cardiac defibrillation and was prescribed amiodarone, but the arrhythmia recurred easily. Therefore, percutaneous transluminal septal myocardial ablation (PTSMA) was performed to prevent AF. The procedure entailed transient complete atrioventricular block (CAVB), which was resolved after a few hours. Four days later, CAVB recurred and advanced to fatal ventricular asystole without escape rhythm. The patient was resuscitated instantaneously and recovered without brain damage. Finally, a DDD permanent pacemaker was implanted 10days after the procedure. Except for conduction problems, his cardiac condition was good after PTSMA, as paroxysmal AF disappeared and LVOT-PG was markedly decreased. CAVB is a well-known complication of PTSMA, but fatal ventricular asystole several days after the procedure is rare. Intensive care is required after PTSMA implementation.