Arrhythmia-induced cardiomyopathy: A potentially reversible cause of refractory cardiogenic shock requiring venoarterial extracorporeal membrane oxygenation

BACKGROUND The most severe form of arrhythmia-induced car-diomyopathy in adults-refractory cardiogenic shock requiring me-chanical circulatory support-has rarely been reported. OBJECTIVE The purpose of this study was to describe the manage-ment of critically ill patients admitted for acute, nonischemic, or worsening of previously known cardiac dysfunction and recent-onset supraventricular arrhythmia who developed refractory cardio-genic shock requiring venoarterial extracorporeal membrane oxygenation (VA-ECMO). METHODS This study is a retrospective analysis of prospectively collected data. RESULTS Between 2004 and 2018, 35 patients received VA-ECMO for acute, nonischemic cardiogenic shock and recent supraventric-ular arrhythmia (77% atrial fibrillation [AF]). Cardiogenic shock was the first disease manifestation in 21 patients (60%). Character-istics at ECMO implantation [median (interquartile range)] were Sequential Organ Failure Assessment score 10 (7-13); inotrope score 29 (11-80); left ventricular ejection (LVEF) fraction 10% (10%-15%); and lactate level 8 (4-11) mmol/L. For 12 patients, amiodarone and/or electric cardioversion successfully reduced arrhythmia, improved LVEF, and enabled weaning off VA-ECMO; 11 had long-term survival without transplantation or long-term assist device. Eight patients experiencing arrhythmia-reduction failure underwent ablation procedures (7 atrioventricular node [AVN] with pacing, 1 atrial tachycardia) and were weaned off VA-ECMO; 7 survived. Of the remaining 15 patients without arrhythmia reduc-tion or ablation, only the 6 bridged to heart transplantation or left ventricular (LV) assist device survived. CONCLUSION Arrhythmia-induced cardiomyopathy, mainly AF-related, is an underrecognized cause of refractory cardiogenic shock and should be considered in patients with nonischemic cardiogenic shock and recent-onset supraventricular arrhythmia. VA-ECMO support allowed safe arrhythmia reduction or rate control by AVN ablation while awaiting recovery, even among those with severe LV dilation. (C) 2021 Heart Rhythm Society. All rights reserved.

Automated summary

This study retrospectively analyzed 35 patients who received VA-ECMO for acute, nonischemic cardiogenic shock and recent supraventricular arrhythmia. Some patients were successfully weaned off VA-ECMO through arrhythmia reduction using amiodarone or electric cardioversion.