Magnetic resonance myocardial strain features of hypertrophic cardiomyopathy preserved ejection fraction based on myocardial segmental thickness
Objective To analyze the left ventricular myocardial strain parameters in patients with hypertrophic cardiomyopathy preserved ejection fraction(HCMpEF),and to explore its relationship with myocardial segmental thickness.Methods Sixty patients with HCMpEF in Fuwai Central China Cardiovascular Hospital from January 2018 to December 2022 were included as the HCM group,and 30 healthy subjects receiving physical examination in the same period were as controls(control group).Both groups were performed 3.0T cardiac magnetic resonance.The left ventricular function parameters were measured,including left ventricular end-diastolic volume index(LVEDVI),left ventricular end-systolic volume index(LVESVI),left ventricular stroke volume index(LVSVI),left ventricular end-diastolic mass index(LVEDMI)and left ventricular ejection fraction(LVEF).Feature tracking technique was used to measure the left ventricular strain parameters as radial strain(RS),circumferential strain(CS),longitudinal strain(LS),peak systolic radial strain rate(Ps-RSr),peak diastolic radial strain rate(Pd-RSr),peak systolic circumferential strain rate(Ps-CSr),peak diastolic circumferential strain rate(Pd-CSr),peak systolic longitudinal strain rate(Ps-LSr),and peak diastolic longitudinal strain rate(Pd-LSr).The left ventricular myocardium was divided into 16 segments according to the American Heart Association standardized myocardial segmentation.The maximum wall thickness(MWT)was measured.According to the left ventricular end-diastolic average wall thickness(AWT),the myocardial segments of HCMpEF patients were divided into the group A(AWT＜8 mm),group B(8 mm≤AWT＜10 mm),group C(10 mm≤AWT＜15 mm)and group D(AWT≥15 mm).The left ventricular function and strain parameters were compared between the HCM group and the control group,and the left ventricular strain parameters were compared among the control group and group A-D.Results The MWT and LVEDMI were higher in the HCM group[(24.00±6.35)mm,(88.24±26.74)g/m2]than those in the control group[(8.17±1.12)mm,(46.62±10.24)g/m2](t=-13.508,P＜0.001;t=-8.212,P＜0.001),and the RS,CS,LS,Ps-RSr,Pd-RSr,Ps-CSr,Pd-CSr,Ps-LSr and Pd-LSr were lower in the HCM group[(32.93±7.16)％,(-18.35±2.60)％,(-14.63±2.73)％,(1.80±0.36)s-1,(-2.13±0.57)s-1,(-1.06±0.14)s-1,(1.02±0.19)s-1,(-1.23±0.27)s-1,(1.11±0.28)s-1]than those in the control group[(42.65±4.13)％,(-22.10±1.04)％,(-20.64±1.90)％,(2.45±0.59)s-1,(-3.25±0.18)s-1,(-1.30±0.23)s-1,(1.53±0.20)s-1,(-1.54±0.37)s-1,(1.85±0.49)s-1](t=-10.825 to 11.570,all P values＜0.05).There were no significant differences in the LVEDVI,LVESVI,LVSVI and LVEF between the HCM group[(78.26±15.07)mL/m2,(31.23±6.61)mL/m2,(47.04±11.79)mL/m2,(59.74±6.65)％]and the control group[(78.22±15.07)mL/m2,(31.85±7.17)mL/m2,(46.37±10.29)mL/m2,(59.18±5.77)％](t=-0.392 to 0.410,all P values＞0.05).There were 960 segments in the HCMpEF group,including 252 segments in the group A with AWT of(6.53±0.89)mm,208 segments in the group B with AWT of(8.96±0.61)mm,346 segments in the group C with AWT of(12.05±1.44)mm and 154 segments in the group D with AWT of(18.59±3.23)mm.There were 480 segments in the control group with AWT of(5.58±1.10)mm.The RS,CS,LS,Ps-RSr,Pd-RSr,Ps-CSr,Pd-CSr,Ps-LSr and Pd-LSr showed significant differences in five groups(F=34.109-237.461,all P values＜0.05).In the control group and group A-D,the LS[(-20.70±6.41)％,(-18.73±6.19)％,(-16.01±7.28)％,(-13.02±5.90)％,(-10.06±5.77)％],Ps-RSr[(2.45±0.96)s-1,(2.24±0.85)s-1,(1.87±0.64)s-1,(1.64±0.60)s-1,(1.27±0.49)s-1],Pd-RSr[(-3.34±1.55)s-1,(-2.93±1.38)s-1,(-2.38±1.12)s-1,(-1.83±1.00)s-1,(-1.22±0.81)s-1],Ps-CSr[(-1.30±0.37)s-1,(-1.17±0.32)s-1,(-1.08±0.24)s-1,(-1.02±0.28)s-1,(-0.88±0.27)s-1],Pd-CSr[(1.53±0.50)s-1,(1.25±0.44)s-1,(1.11±0.41)s-1,(0.92±0.34)s-1,(0.73±0.34)s-1],Ps-LSr[(-1.58±0.65)s-1,(-1.39±0.67)s-1,(-1.27±0.66)s-1,(-1.15±0.62)s-1,(-1.03±0.53)s-1],and Pd-LSr[(1.87±0.92)s-1,(1.29±0.60)s-1,(1.17±0.60)s-1,(1.00±0.54)s-1,(0.88±0.45)s-1]decreased sequentially(P＜0.05).In group A-D,the RS[(42.73±13.18)％,(35.29±10.82)％,(29.85±10.52)％,(20.11±8.56)％],and CS[(-21.89±3.94)％,(-19.57±3.66)％,(-17.43±4.01)％,(-12.90±3.85)％]decreased sequentially(P＜0.05).The RS and CS were lower in the group B,C and D than those in the control group(P＜0.05).There were no significant differences in the RS and CS between the group A and the control group(P＞0.05).Conclusions The left ventricular myocardial strain in all directions decreases to varying degrees in patients with HCMpEF,and as myocardial segmental thickness increases,the myocardial segmental strain and strain rate decrease gradually.The LS decreases when the myocardial segmental thickness is normal,and is more sensitive than RS and CS.
hypertrophic cardiomyopathycardiac magnetic resonancemyocardial segmentsstrainfeature tracking technique
NETL
NSTL
万方数据
