Objective To evaluate the prognosis of patients with HCM by myocardial work combined with cardiopulmonary exercise test (CPET)

and to explore the correlation between myocardial work parameters

CPET parameters and left ventricular wall thickness. Methods A total of 55 patients with non-obstructive HCM (40 males and 15 females

average age 22-66 years) diagnosed in the First Hospital of Longyan City of Fujian Province from January 2022 to March 2023 were selected

and 55 healthy volunteers were selected as the control group. Routine echocardiographic data were collected and compared between the two groups. HCM patients and control group underwent cardiopulmonary exercise test. The differences of cardiopulmonary exercise test parameters and myocardial work parameters were compared between the two groups

and the changes of myocardial work parameters before and after cardiopulmonary exercise test were compared between the two groups. Results The maximum ventricular wall thickness (MWT)

left atrial end-diastolic diameter (LAD) and E/e 'were significantly increased in the HCM group compared with the control group (P<0.05). Compared with the control group

the global longitudinal strain (GLS)

myocardial work index (GWI) and active work (GCW) of the HCM group before cardiopulmonary exercise test were significantly decreased

and the time dispersion of longitudinal strain to peak (PSD) was significantly increased (P<0.05). However

no significant statistical significance was found in GWW. Compared with the control group

the Peak oxygen uptake (Peak VO2)

anaerobic threshold (AT)

oxygen pulse (VO2/HR) and metabolic equivalent (METs) of the HCM group were significantly decreased (P<0.05). There was no significant increase in the slope of VE/V?CO2. There was no significant increase in GCW and PSD before and after cardiopulmonary exercise test in HCM group. In the control group

GCW increased significantly before and after cardiopulmonary exercise test

but PSD did not change significantly. The maximal left ventricular wall thickness was positively correlated with PSD（r=0.88）， negatively correlated with GCW（r=-0.84）， and not negatively correlated with VO2（r=-0.48）. Conclusions Myocardial work combined with CPET can effectively evaluate the prognosis of patients with HCM. There is a negative correlation between myocardial work parameters and left ventricular wall thickness

while there is no significant correlation between CPET parameters and left ventricular wall thickness.