Parameters of repolarization heterogeneity are associated with myocardial recovery in acute heart failure.

Heart failure (HF) with recovered ejection fraction (HFrecEF) is an increasingly recognized yet not well understood phenotype. Little is known about electrical parameters associated with myocardial recovery in acute systolic HF. We identified a subset of 87 patients from a non-ischemic cardiomyopathy cohort with left ventricular ejection fraction (LVEF) < 40% during index HF hospitalization. HFrecEF was defined as follow-up LVEF ≥40% and ≥ 10% improvement from baseline. We analyzed baseline and follow up electrocardiograms (ECG) in this group for several electrical parameters known to reflect repolarization heterogeneity. Among 87 patients, 30 (34%) patients recovered in a median of 122 (IQR: 58-275) days after index hospitalization. Baseline demographics were similar among HFrecEF versus persistent HFrEF except for increased diabetes in the persistent HFrEF cohort. Patients with HFrecEF had baseline decreased QRST angle, decreased QT dispersion, and less negative signed JT area compared to persistent HFrEF. Patients with HFrecEF had greater decrease in QT dispersion and QTc duration, and greater increase in the signed JT and TpTe areas over time. Baseline QRST angle correlated with longitudinal and circumferential strain and myocardial systolic performance (MSP). Signed JT area correlated with increased baseline LVEF, smaller baseline LV dimensions, increased longitudinal and circumferential strain, and MSP. Signed TpTe correlated with increased longitudinal and circumferential strain, and MSP. Several conventional and novel ECG parameters that reflect repolarization heterogeneity may differentiate patients with acute HF who ultimately recover LVEF. These parameters are associated with baseline structural parameters and are dynamic during recovery. • Heart failure with recovered ejection fraction is a newly recognized phenotype. • Increased repolarization heterogeneity on ECG is associated with adverse outcomes. • Repolarization is less heterogeneous on ECG in patients with HFrEF who recover. • Repolarization heterogeneity correlates with baseline structural parameters. • ECG parameters of repolarization are dynamic during the recovery process. [ABSTRACT FROM AUTHOR]