Study on the application of exercise stress echocardiography combined with layer-sepcific strain in patients with essential hypertension / 中华超声影像学杂志

ABSTRACT

Objective:To evaluate the diagnostic value of exercise stress echocardiography combined with left ventricular two-dimensional speckle tracking layer-specific strain technique in evaluating subclinical myocardial damage and reserve function in patients with hypertension.Methods:A total of 51 healthy subjects(control group) and 55 hypertensive patients (hypertension group) were enrolled in the treadmill exercise stress test in Sichuan Provincial People′s Hospital from October 2018 to January 2020. According to the European Guidelines for the Prevention and Treatment of Hypertension, the inclusion criteria for patients with hypertension were blood pressure≥140/90 mmHg or who explicitly took antihypertensive drugs, and related cardiovascular diseases were excluded. The conventional parameters of resting and peak exercise, including left ventricular mass index, left ventricular end-diastolic volume index and left ventricular ejection fraction et al, were analyzed by speckle tracking software in two groups. According to the standard images in the resting and peak exercise, the endocardium /mid-myocardium /epicardium of left ventricular (three-, two-, four-chamber and global) longitudinal strain and circumferential strain (papillary muscle level) were compared respectively in two groups. The characteristics of strain differences and the systolic function reserve between the resting and peak exercise were evaluated.Results:There were significant differences in conventional ultrasound parameters between resting and peak exercise period in hypertension group, except E/A and e/a ratio (all P<0.05), and E/e value increased significantly(12.1±0.38) during peak exercise, indicating impaired diastolic reserve function. The longitudinal and circumferential layer-specific strain values from endocardial to epicardial were gradually decreased in both two groups. Compared with the control group, the resting longitudinal and circumferential endocardial strain values in hypertensive group were decreased, and the differences were more obvious at peak status, for instance global longitudinal endocardium strain at rest[control group (24.4±1.5)%, hypertension group (20.4±2.3)%], peak status[control group (30.8±2.8)%, hypertension group (22.8±2.9)%]( P<0.05). There were no significant differences of the partial layer-specific strain values between the peak exercise and resting status in hypertension group, while peak layer-specific strain of the control group were all significantly increased, suggesting that the left ventricular systolic reserve function of hypertension patients was lower than that of the control group. Conclusions:Left ventricular layer-specific strain can effectively evaluate the myocardial function in patients with hypertension, especially the endocardial strain can be used as an indicator parameter, and the peak exercise stress state is more sensitive. The systolic and diastolic reserve function of the left ventricle in patients with hypertension at the peak period are reduced to different degrees. Exercise stress echocardiography combined with left ventricular layer-specific strain technique can be used as a new method for detection of myocardial function impairment in patients with hypertension.