Quantification of left ventricular performance in different phenotypes of hypertrophic cardiomyopathy / 中华超声影像学杂志

ABSTRACT

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 groupspatients 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 .