Abstract
Left ventricular myocardial work (LVMW) represents an innovative tool based on echocardiography designed to assess left ventricular (LV) performance in conjunction with LV pressure patterns. Although previous studies have compared differences in LVMW among patients with Fabry disease (FD), cardiac amyloidosis (CA), and hypertension at rest, there is limited research on the characteristics of LVMW in patients with FD during exercise. This study aims to explore the characteristics of LVMW at rest and during exercise in patients with FD and the value of LVMW combined with stress echocardiography for the early detection of impaired cardiac function in subclinical Fabry patients. This cross-sectional study included 54 participants, comprising 23 healthy individuals and 31 patients with FD. All participants underwent comprehensive two-dimensional echocardiography and semi-supine exercise stress echocardiography tests. At rest, individuals with FD exhibited markedly lower LV global longitudinal strain (LVGLS), LV global myocardial constructive work (LVGCW), LV global myocardial work efficiency (LVGWE), and LV global myocardial work index (LVGWI) compared to healthy controls. During exercise, LVGLS, LVGWI, LVGCW, and LV global wasted myocardial work (LVGWW) markedly increased in patients with FD and controls, while LVGWE decreased. However, across the four phases (rest, 25 W, peak, and recovery), patients with FD consistently demonstrated lower LVGLS, LVGWI, LVGWE, and LVGCW compared to controls. Moreover, the rise in LVGWI and LVGCW from the rest phase to the peak stage was markedly smaller in individuals with FD than in controls. A moderate correlation was found between LVGWI and LVGWE with LV mass index (LVMI) in individuals with FD (LVGWI: r = - 0.57, P < 0.05; LVGWE: r = - 0.68, P < 0.001). Additionally, individuals with FD with LV hypertrophy (LVH) exhibited lower LVGLS, LVGWE, and LVGCW from the rest to peak than those without LVH. Individuals with FD who had normal LVGLS at rest or those without LVH still showed markedly lower LVGWI than controls during the resting phase. Additionally, at peak exercise, LVGLS, LVGWI, and LVGCW were diminished significantly in the individuals with FD relative to the control cohort. ROC curve analysis in both resting and exercising states showed that LVGWI (rest: AUC 0.86, sensitivity 87%, specificity 74%; peak: AUC 0.94, sensitivity 71%, specificity 96%;) and LVGCW (rest: AUC 0.82, sensitivity 87%, specificity 70%; peak: AUC 0.92, sensitivity 84%, specificity 87%;) than LVGLS (resting: AUC 0.79, sensitivity 61%, specificity 87%; peak: AUC 0.88, sensitivity of 77%, and specificity of 87%) have a higher value in the diagnosis of FD. Patients with FD have markedly lower LVGWI, LVGWE, and LVGCW compared to the healthy controls, and these reductions are more prominent during exercise. Although LVGWI and LVGCW increase during exercise in patients with FD, the rate of increase is reduced, indicating impaired myocardial metabolism and energy utilization efficiency, especially in patients with FD with LVH. Additionally, LVMW combined with Stress Echocardiography allows early detection of impaired cardiac function in Fabry patients.