基于4D Flow CMR技术评价心肌纤维化对肥厚型心肌病患者左室舒张功能障碍的影响OA北大核心CSTPCD

Objective:Four-dimensional flow(4D Flow)cardiac magnetic resonance(CMR)technology was used to evaluate the presence of left ventricular diastolic dysfunction in patients with hypertrophic cardiomyopathy(HCM),and the effect of myocardial fibrosis on left ventricular diastolic function in HCM patients was explored.Materials and Methods:A total of 44 HCM patients were prospectively enrolled,and they were divided into HCM late gadolinium enhancement(LGE)(+)group(25 cases)and HCM LGE(-)group(19 cases)according to whether the patients had LGE,and 31 healthy controls were included in the same period.All three groups underwent 3.0 T magnetic resonance imaging,including steady-state free precession sequences and 4D Flow CMR scans.Analysis using CVI42 post-processing software included cardiac functional parameters and mitral valve blood flow velocity parameters.Clinical and imaging parameters were compared among the three groups using one-way analysis of variance or Mann-Whitney U test.Correlation analysis was performed between early diastolic mean blood flow velocity(E)and cardiac functional parameters.Results:The left ventricular mass(LVmass)and global peak wall thickness(GPWT)of HCM patients were greater than those of healthy controls,and the GPWT of HCM patients with myocardial fibrosis increased more significantly than that of HCM patients without myocardial fibrosis[HCM LGE(+)group vs.HCM LGE(-)group vs.healthy control group];[LVmass:157.34(122.24,194.38)g vs.148.29(131.79,189.83)g vs.85.73(73.00,94.02)g;GPWT:20.04(16.76,24.99)mm vs.17.46(16.19,19.99)mm vs.9.47(8.35,10.92)mm](P<0.001);The peak early diastolic mean blood flow velocity(peak E)of HCM patients with myocardial fibrosis was lower than that of HCM patients without myocardial fibrosis,and was lower than that of healthy control group[HCM LGE(+)group vs.HCM LGE(-)group vs.healthy control group:(30.03±11.33)cm/s vs.(38.05±12.03)cm/s vs.(47.44±10.82)cm/s](P<0.001),while there was no significant difference in the peak value of mean blood flow velocity(peak A)in late diastolic period between the three groups,and the E/A value of HCM patients with myocardial fibrosis was significantly lower than that of the healthy control group(1.10±0.61 vs.1.74±0.85)(P<0.05).The mean blood flow velocity at the mitral valve level in early diastolic was negatively correlated with GPWT and LVmass(r=-0.593/r=-0.371,P<0.001/P=0.001).Conclusions:Based on 4D Flow CMR,it can not only accurately measure the blood flow velocity from a three-dimensional perspective,but also quantitatively evaluate the effects of left ventricular diastolic dysfunction and myocardial fibrosis on the left ventricular diastolic function of HCM patients from the hemodynamic aspect.