Phenotyping of Arrhythmia-induced Cardiomyopathy: From Bench to Bedside and Back

Abstract Purpose of Review Arrhythmia-induced cardiomyopathy (AIC) is an increasingly recognized and potentially reversible cause or modifier of heart failure. This review summarizes experimental and clinical evidence with a focus on atrial fibrillation (AFib)-induced left ventricular systolic dysfunction. Recent Findings Recent studies demonstrate that AIC extends beyond tachycardia alone and involves rhythm irregularity, loss of atrioventricular synchrony, altered calcium handling, oxidative stress, mitochondrial dysfunction and substrate vulnerability. Clinical trials demonstrate the superiority of rhythm control therapy by catheter ablation in patients with AFib and heart failure. Emerging data illustrate the importance of phenotyping of AIC according to myocardial substrate and individual ventricular response to AFib. Summary AIC should be considered as a heterogeneous spectrum. Refined phenotyping may improve prediction of recovery and guide specific and individual therapy.