Cardiovascular magnetic resonance-based predictors of complete left ventricular systolic functional recovery after rhythm restoration in patients with atrial tachyarrhythmia.

Aims: To establish a cardiovascular magnetic resonance (CMR)-based prediction model for complete systolic left ventricular ejection fraction (LVEF) recovery for the distinction of 'arrhythmia-induced' from 'arrhythmia-mediated' cardiomyopathy in patients with atrial tachyarrhythmias.

Methods And Results: Two hundred and fifty-three tachyarrhythmia patients referred for catheter ablation were enrolled and underwent CMR baseline imaging; patients with a reduced LVEF <50% at baseline and CMR imaging at 3-month follow-up after successful rhythm restoration constituted the final study population (n = 134). CMR at baseline consisted of standard functional cine imaging, determination of extracellular volume, and late gadolinium enhancement (LGE) imaging; follow-up CMR comprised standard functional cine imaging. Left ventricular end-diastolic volume index (LVEDVI) measurements were categorized in 'opposite', 'normal', and 'enlarged'. At follow-up, 80% (107/134) presented with complete LVEF recovery, while in 20% (27/134) persistent LVEF impairment was observed. LVEDVI and LGE were independent predictors of complete LVEF recovery with LGE adding significant incremental value on logistic regression modelling. Model-derived probabilities for complete LVEF recovery in LVEDVI categories of opposite, normal, and enlarged for LGE negativity and positivity were 94%, 85%, and 29% and 77%, 55%, and 8%, respectively.

Conclusion: CMR-derived assessment of LVEDVI category and LGE allowed for identification of arrhythmia-induced cardiomyopathy with acceptable discriminative performance. Probabilities for complete LVEF recovery for the combination of opposite LVEDVI/LGE negativity and enlarged LVEDVI/LGE positivity were 94% and 8%, respectively. The CMR-based prediction model of complete LVEF recovery can be used to perform upfront stratification in atrial tachyarrhythmia-related LVEF impairment.