P2614Comparison of global longitudinal strain and ejection fraction in correlation to NT-proBNP in ischemic and non-ischemic heart failure

Abstract

Abstract Background In chronic heart failure (CHF) NT-proBNP and left ventricular ejection fraction (LVEF) by echocardiography are standard diagnostic as well as follow-up markers and are known to correlate with prognosis. Speckle-tracking echocardiography is a more recent technique to quantify myocardial deformation as a measurement of left ventricular function with potential benefits over LVEF. Purpose The purpose of this investigation was to analyse the cross-sectional relationship between 2D speckle tracking-derived global longitudinal strain (GLS) and NT-proBNP plasma levels in a prospective cohort of ischemic and non-ischemic CHF patients. Methods We enrolled 205 patients with chronic heart failure. Major inclusion criteria were age over 18 years, stable disease with absence of unplanned hospitalization or change in medication or device therapy in the previous month or major surgery in the previous 3 months. CHF treatment had to be according to the recommendations of the ESC CHF guidelines 2016 and LVEF had to be below 50%. Patient history, physical examination and an extensive echocardiography exam were performed. Lab results included NT-proBNP. Manual longitudinal strain was calculated using EchoPAC (General Electric Medical Systems, Horten, Norway) by a single and blinded examiner. LVEF was measured using Simpson's biplane method. Results 205 patients included in the study. The baseline characteristics included mean age 65.0 years and 75% male. Mean GLS was −9.6% (SD ±4.5%) and median NT-proBNP 1269.5 (IQR 379.5–2759.5) ng/ml. The CHF aetiology was 70.0% ischemic vs 30.0% non-ischemic. There was a significant negative correlation between GLS and NT-proBNP (Pearson r=0.239, p=0.029), this was not significant for LVEF and NT-proBNP (Pearson r=0.149, p=0.228).In a multivariate regression analysis adjusted for age, sex, NYHA classification and HF aetiology, GLS remained significantly correlated with NT-proBNP (adjusted beta-coefficient= 0.289, p=0.011). Furthermore, in contrast to LVEF, GLS showed a significant correlation to NT-proBNP in patients with ischemic (Pearson r=0.266, p=0.049) as well as non-ischemic aetiology of heart failure (Pearson r=0.434, p=0.034). Conclusion Global longitudinal strain, not LVEF, was significantly correlated with NT-proBNP in patients with CHF, independently of age, sex, symptoms or heart failure aetiology. This shows that speckle-tracking might be superior to LVEF for the assessment of left ventricular function in CHF.