Left ventricular performance and dyssynchrony in heart failure and normal ejection fraction: assessment by stress echocardiography

Abstract

Purpose: We evaluated the left ventricular (LV) performance and dyssynchrony in patients with heart failure and normal ejection fraction (HFNEF) during exercise as compared to those with heart failure and reduced ejection fraction (HFREF) and healthy subjects. Methods: All subjects received echocardiographic (Vivid7) examination with symptom-limited (fatigue or dyspnea) exercise testing on a semi-recumbent and tilting bicycle ergometer. The exercise images for two-dimensional (2D) speckle tracking were acquired with submaximal heart rate of 90-100bpm, while M-mode and tissue Doppler Imaging (TDI) exercise images were stored with attainment of >85% of maximal age-predicted heart rate response. Results: Stress echocardiography exams were performed in 40 HFNEF (aged 65±9 years; 53% male), 40 HFREF (aged 62±9 years; 90% male) and 30 normals (aged 56±5 years; 33% male). Trends of progressive decline in 2D global circumferential and radial strains (GCS & GRS), global longitudinal strains (2D GLS & GLS_TDI), pulsed-wave TDI systolic velocity (septal S') and M-mode mitral annular plane systolic excursion (MAPSE) were observed from control, HFNEF to HFREF groups (all p<0.05). LV twist was preserved in HFNEF but reduced in HFREF patients as compared to normals (p<0.001). Diastolic function measured by spetal e' progressively decreased from controls to HFNEF followed by HFREF (all p<0.05). LV filling pressure (septal E/e'), stroke volume and cardiac indices (LVSI & LVCI) were preserved in HFNEF but deteriorated in HFREF than controls. LV dyssynchrony parameters (standard deviation of time to peak systolic velocity, Ts-SD) were similar in all groups. Conclusions: This study provides the reference values of LV performance and dyssynchrony during exercise in HFNEF and knowledge about these changes provide important insights for future clinical studies.