肥厚型心肌病患者左心房功能的应变率评价

目的 探讨应变率成像技术评价肥厚型心肌病(HCM)患者左心房功能的价值.方法 根据左室流出道压差将36例HCM患者分为两组:非梗阻性HCM组[左室流出道压差<20 mmHg(1 mm Hg=0.133 kPa)]和梗阻性HCM组(左室流出道压差≥20mmHg).分别采集各受试者的心尖二腔、心尖四腔和心尖左室长轴观TVI图像,测量心室收缩期左心房峰值应变率(LASRs)、心室舒张早期左心房峰值应变率(LASRe)、心房收缩期左心房峰值应变率(LASRa)和心室舒张早期空间隔峰值应变率(LVSRe),计算其平均值(mLASRs、mLASRe、mLASRa和mLVSRe).结果 与对照组比较,非梗阻性HCM组和梗阻性HCM组mLASRs、mLASRe和mLVSRe减低,mLASRa增高,差异均有统计学意义(P<0.05).与非梗阻性HCM组比较,梗阻性HCM组mLASRe和mLVSRe减低,mLASRa增高,差异均有统计学意义(P<0.05).梗阻性HCM组与非梗阻性HCM组的mLASRa和mLVSRc均呈现著负相关(r=-0.67,-0.75;P<0.01,0.01).结论 HCM患者左心房功能发生改变,表现为储蓄功能和管道功能减低,辅泵功能增加.应变率成像技术能够评价左心房功能,为临床提供有价值的信息.

Evaluation of left atrial function in patients with hypertrophic cardiomyopathy by strain rate imaging

Objective To assess the value of strain rate imaging in detecting left atrial function in patients with hypertrophic cardiomyopathy(HCM).Methods Thirty-six patients with HCM were divided into two groups according to the pressure gradients of left ventricular outflow tract:the group of obstructive hypertrophic cardiomyopathy(OHCM)and the group of nonobstructive hypertrophic cardiomyopathy (NHCM).Tissue velocity imaging of all patients and controls were accepted in apical two,four and long axis chamber views.Strain rate imaging was performed on those patients and controls.Peak strain rate was measured at each segment(septal,lateral,posterior,anterior,and inferior walls of left atrium,interventricular septum)and mean peak systolic left atrial SR(mLASRs),mean peak early diastolic left atrial SR(mLASRe),mean peak atrial systolic left atrial SR(mLASRa)and mean peak early diastolic left ventricular SR(mLVSRe)were calculated by averaging data in all segments.Results mLASRs,mLASRe and mLVSRe of OHCM and NHCM were significantly lower than those of controls,while mLASRa of OHCM and N HCM were significantly higher than those of controls(P<0.05).Moreover,compared with NHCM,mLASRs,mLASRe and mLVSRe of OHCM were significantly lower,mLASRa of OHCM was significantly higher.mLASRa correlated inversely with mLVSRe of OHCM and N HCM respectively(r=-0.67,-0.75;P<0.01,0.01).Conclusions The change of left atrial function of HCM presented as reservoir and conduit functions decreased and pump function increased.Strain rate imaging could evaluate the left atrial function and provide important clinical information.