Left ventricular global longitudinal strain is superior to ejection fraction for prognostication in ebstein anomaly

Abstract

Abstract Background Certain factors such as left ventricular (LV) geometry and loading conditions affect the validity and reliability of LV ejection fraction (LVEF) as a true measure of LV contractility. LV global longitudinal strain (LVGLS) is less sensitive to these factors, and it has superior prognostic performance in patients with acquired heart disease. The purpose of this study was to determine the clinical implications of using LVGLS (instead of LVEF) as the measure of LV systolic function in adults with Ebstein anomaly given the inherent abnormalities of LV geometry and preload in this population. Methods Retrospective cohort study of 673 adults with Ebstein anomaly (2003–2018). We hypothesized that LVGLS had a stronger correlation with heart failure indices and transplant-free survival compared to LVEF. Results Compared to LVEF, LVGLS had stronger correlations with cardiac index (r=0.46 vs r=0.21, p=0.007), glomerular filtration rate (r=0.57 vs r=0.19, p<0.001), and NT-proBNP (r=−0.64 vs r=−0.41, p=0.01). Of 673 patients, 514 (76%) had normal LV systolic function (LVGLSNormal-LVEFNormal), 87 (13%) had subclinical LV dysfunction (LVGLSLow-LVEFNormal) and 66 (10%) had overt LV dysfunction (LVGLSLow-LVEFLow). Compared to the overt LV dysfunction group, the subclinical LV dysfunction group had similar 10-year transplant-free survival (64% vs 63%, p=0.6), but were less likely to be on heart failure therapy (12% vs 82%, p<0.001). LVGLS (but not LVEF) was the independent predictor of transplant-free survival Conclusions LVGLS provided more robust risk stratification and prognostication than LVEF in patients with Ebstein anomaly, and patients with low LVGLS had reduced transplant-free survival regardless of LVEF. The use of LVGLS (rather than LVEF) as the measure of LV systolic function has important clinical implications with regards to initiation of medical and surgical therapies. Funding Acknowledgement Type of funding sources: None.