二维斑点追踪技术评价初发型心绞痛患者的左房节段功能

目的应用二维斑点追踪显像（speckle tracking imaging，STI）技术评价初发型心绞痛患者的左房壁各节段功能。方法选择50例明确诊断为初发型心绞痛患者及40名正常人测定其左房被动射血分数（LAPEF）和左房主动射血分数（LAAEF）,应用STI技术测定左房壁各节段（后侧壁、房间隔、侧壁、前壁、下壁）应变及应变率曲线，获取左室收缩期左房壁各节段峰值应变（Ss）及应变率（SRs），左室舒张早期左房壁各节段峰值应变率（SRe），左室舒张晚期左房各节段峰值应变率（SRa）。结果心绞痛组较正常对照组，左房存储功能指标：各节段Ss均减低，SRs减低，左房最小容积（LAVmin）显著增大；左房管道功能指标：SRe、LAPEF显著减低；左房辅泵功能指标：左房前壁及下壁SRa显著减低。LAAEF及余左房壁SRa无统计学差异。结论初发型心绞痛患者左房管道功能明显减低，存储功能增强，泵功能部分受损。二维斑点追踪技术可以评价初发型心绞痛患者左房壁各节段的功能。

Assessment of Each Segment of Left Atrial Function by Two-dimensional Speckle Tracking Imaging in Patients with Initial Onset Angina Pectoris

Objective To evaluate each segment of left atrial function by two-dimensional speckle tracking imaging（STI） in patients with initial onset angina pectoris. Methods 50 patients with initial onset angina pectoris and 40 age-matched normal individuals were included in this study, and were examined by conventional echocardiography to measure left atrial passive ejection fraction（LAPEF） and left atrial active ejection fraetion（LAAEF）.Strain and strain rate（SR）was measured at each segment of left atrium（inferolateral,septal,lateral,anterior, inferior wall） by STI,including a peak positive LA Strain and SR（Ss and SRs） at the beginning of LV systole,peak negative SR（SRe）at the beginning of LV diastole and peak negative SR（SRa） during LA contraction. Results Compared with health subjects,the index of left atrial reservoir function in patients：Ss and SRs of each segment reduced significantly, minimal volume of left atrium（LAVmin） increased significantly;the index of left atrial conduit function：SRe and LAPEF reduced significantly;the index of left atrial pump function：SRa（anterior and inferior） reduced significantly, SRa（inferolateral, septal, lateral）and LAAEF revealed no significant difference. Conclusions Left atrial conduit function is serious reduced,reservoir function is increased,and pump function is moderate reduced in patients with initial onset angina pectoris.STI is a new tool that can be used to evaluate left atrial function of these patients.