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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.
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Objective@#To evaluate the characteristics of left ventricular structure, function, myocardial mechanics, hemodynamics and synchrony in different phenotypes of hypertrophic cardiomyopathy (HCM) using state-of-the-art echocardiography.@*Methods@#A consecutive series of 85 adult HCM patients who were admitted to the Xi Jing HCM center from January 2016 to November 2017 were collected. According to the peak left ventricular outflow tract pressure gradient in exercise stress echocardiography, the patients were divided into three groups: patients with non-obstructive HCM (n=28), those with labile-obstructive HCM (n=27), and those with obstructive HCM (n=30). In addition, 16 normal family members of HCM patients were included as control group. Two-dimensional speckle tracking imaging, tissue Doppler imaging and exercise stress echocardiography were used to evaluate the left ventricular function in resting and exercise states.@*Results@#①As compared with the control group, left ventricular end-diastolic diameter decreased and left ventricular ejection fraction increased in all three HCM groups(all P<0.05). Left ventricular maximum wall thickness and left ventricular mass index were the highest in obstructive HCM, followed by labile-obstructive and non-obstructive HCM, and the lowest in the control group (all P<0.05). ②At rest, the left ventricular global longitudinal, circumferential and radial strain (GLS, GCS and GRS), as well as the twist of obstructive HCM were significantly lower than the other three groups (all P<0.05). As compared with the control group, the GLS and twist decreased in the labile-obstructive and non-obstructive HCM(all P<0.05), but there were no significant changes of GCS and GRS (all P>0.05). The obstructive HCM had the lowest mitral annular plane systolic excursion (MAPSE) and s′, and the longest systolic peaking time standard deviation(Ts-SD) and early diastolic peaking time standard deviation(Te-SD) (all P<0.05). The left ventricular diastolic function of obstructive HCM (e′, the E/e′ ratio and the left atrial volume index) was the worst, labile-obstruction and non-obstructive HCM were better, and the control group was the best (all P<0.001). ③During exercise, the GLS, GCS, GRS, twist of the left ventricle and the MAPSE were the lowest in the obstructive HCM, which increased in the labile-obstructive and non-obstructive HCM, and were best in the control group. The Ts-SD and Te-SD were the shortest in the control group, were prolonged in non-obstructive and labile-obstruction HCM, and were longest in obstructive HCM (all P<0.05). Additionally, the exercise time of the control group was the longest, followed by non-obstructive and labile-obstruction HCM, and the shortest in the obstructive HCM (all P<0.05). The METs of obstructive HCM were significantly lower than the other three groups (all P<0.05).@*Conclusions@#In obstructive HCM, the left ventricular systolic strain and synchronization, as well as the MAPSE, are significantly impaired in patients both at rest and during exercise. The patients with labile-obstructive and non-obstructive HCM have reduced left ventricular GLS, twist, and e′, but normal left ventricular GCS, GRS, synchrony, and MAPSE at rest, which are all impaired during exercise.
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Objective To evaluate the characteristics of left ventricular structure ,function ,myocardial mechanics ,hemodynamics and synchrony in different phenotypes of hypertrophic cardiomyopathy ( HCM ) using state‐of‐the‐art echocardiography . Methods A consecutive series of 85 adult HCM patients w ho were admitted to the Xi Jing HCM center from January 2016 to November 2017 were collected . According to the peak left ventricular outflow tract pressure gradient in exercise stress echocardiography ,the patients were divided into three groups :patients with non‐obstructive HCM ( n ＝28) ,those with labile‐obstructive HCM ( n ＝27) ,and those with obstructive HCM ( n ＝ 30 ) . In addition ,16 normal family members of HCM patients were included as control group . T wo‐dimensional speckle tracking imaging ,tissue Doppler imaging and exercise stress echocardiography were used to evaluate the left ventricular function in resting and exercise states . Results ① As compared with the control group ,left ventricular end‐diastolic diameter decreased and left ventricular ejection fraction increased in all three HCM groups ( all P ＜ 0 .05 ) . Left ventricular maximum wall thickness and left ventricular mass index were the highest in obstructive HCM , followed by labile‐obstructive and non‐obstructive HCM ,and the lowest in the control group ( all P ＜0 .05) . ②A t rest ,the left ventricular global longitudinal ,circumferential and radial strain ( GLS ,GCS and GRS) ,as well as the twist of obstructive HCM were significantly lower than the other three groups ( all P ＜0 .05) . As compared with the control group ,the GLS and twist decreased in the labile‐obstructive and non‐obstructive HCM ( all P ＜0 .05 ) ,but there were no significant changes of GCS and GRS ( all P ＞ 0 .05 ) . T he obstructive HCM had the lowest mitral annular plane systolic excursion ( M APSE ) and s′,and the longest systolic peaking time standard deviation( T s‐SD) and early diastolic peaking time standard deviation ( Te‐SD) ( all P ＜0 .05) . T he left ventricular diastolic function of obstructive HCM ( e′,the E/e′ratio and the left atrial volume index ) was the worst ,labile‐obstruction and non‐obstructive HCM were better ,and the control group was the best ( all P ＜ 0 .001 ) . ③ During exercise ,the GLS ,GCS ,GRS ,twist of the left ventricle and the M APSE were the lowest in the obstructive HCM ,which increased in the labile‐obstructive and non‐obstructive HCM ,and were best in the control group . T he T s‐SD and Te‐SD were the shortest in the control group ,were prolonged in non‐obstructive and labile‐obstruction HCM ,and were longest in obstructive HCM ( all P ＜ 0 .05 ) . Additionally ,the exercise time of the control group was the longest , followed by non‐obstructive and labile‐obstruction HCM ,and the shortest in the obstructive HCM ( all P ＜0 .05) . T he M ET s of obstructive HCM were significantly lower than the other three groups ( all P ＜0 .05) . Conclusions In obstructive HCM ,the left ventricular systolic strain and synchronization ,as well as the M APSE ,are significantly impaired in patients both at rest and during exercise . T he patients with labile‐obstructive and non‐obstructive HCM have reduced left ventricular GLS , twist ,and e′,but normal left ventricular GCS ,GRS ,synchrony ,and M APSE at rest ,which are all impaired during exercise .
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To investigate the association between the change of left ventricular ( LV ) function and mechanical dispersion ( MD ) and exercise capacity in patients with hypertrophic cardiomyopathy ( HCM ) by exercise stress echocardiography . Methods Sixty‐five HCM patients [ 40 cases of hypertrophic non‐obstructive cardiomyopathy ( HNCM ) , 25 cases of hypertrophic obstructive cardiomyopathy ( HOCM ) ] and 25 control subjects were recruited .LV function ,MD and exercise capacity were evaluated by two‐dimensional speckle‐tracking imaging and echocardiography at rest and during exercise ,and the following parameters of LV function were recorded : LV global longitudinal strain ( LVGLS) ,MD ,early diastolic strain rate ( Sre) ,the ratio of peak early diastolic mitral inflow and annulus velocity ( E/e′) ,LV outflow tract gradient ( LVO TG) ; LV functional reserve was assessed by ΔLVGLS and ΔSRe ; exercise capacity was evaluated by metabolic equivalents ( M ET s ) . T he association between the change of LV function and MD and exercise capacity was investigated . Results ①Compared with normal controls ,LVO TG ,E/e′ and MD increased ,and LVGLS ,Sre , ΔLVGLS , ΔSRe and M ET s decreased in HNCM patients at rest and during exercise ( all P ＜ 0 .05 ) . ② LVO TG , E/e′ and MD were further increased ,LVLGS ,Sre ,ΔSRe and M Ets were further reduced in HOCM patients compared with HNCM patients ( all P ＜ 0 .05 ) . ③LVGLS and MD measured at peak exercise were associated with M ET s ( r ＝－0 .68 , P ＜ 0 .001 ; r ＝ －0 .43 , P ＜ 0 .001 ) . ④ ROC curve analysis showed LVGLS had a better predictive value for exercise intolerance in HCM patients ,followed by E/e′ and MD . Conclusions LV function and mechanic reserve are reduced but MD is increased in HCM patients ,especially in HOCM patients . Exercise capacity is associated with LV function and MD ,w hich can predict the reduced exercise capacity in HCM patients .