Can Non-Invasive Global Myocardial Work Index Calculation Improve Exercise Stress Echocardiography?

Abstract

Background: Patients with stage A and B heart failure can have a significant burden of fatigue and poor quality of life despite having normal left ventricular (LV) ejection fraction (EF). Global longitudinal strain (GLS) can detect early changes in LV function. This study evaluates the relationship between LV function with functional capacity and quality of life (QOL) measures in stage A and B heart failure. Methods: A cross-sectional study of patients with stage A and B heart failure (n = 431) to show the relation of echocardiographic parameters with functional capacity and quality of life measures. Functional capacity (6-min walk test (6MWT), quality of life (short form-12 (SF-12) and international measure for physical activity (IPAQ)) were measured. Echocardiogram was used to assess global longitudinal strain (GLS), Ejection fraction (EF), left ventricular mass index (LVMI), left atrial volume index (LAVI), left ventricular end diastolic volume (LVEDV) and E/e'. Results: The mean age was 65 ± 11 years, 72% were men. Mean GLS was −18.1 ± 3%. Univariate analysis showed age (−4.2 (−5.4, −3.1) P < 0.01) GLS (5.8 (1.5, 9.9) P = 0.01), LAVI (−1.5 (−2.9, −0.2) P = 0.03), and Ee' (−7.1 (−9.7,-1.1) P < 0.01) were associated with distance walked in 6 MWT. EF (0.2 (0.1, 0.3) P = 0.01) and GLS (0.5 (0.1, 0.9) P = 0.01) were both associated with higher SF 12 score. And no cardiac parameter was associated with IPAQ score. Conclusion: GLS was associated with measures of functional capacity and one in two measures of QOL in patients stage A and B heart failure.