实时三维超声心动图联合二维斑点追踪成像评价肥厚型心肌病患者左房功能的研究

Evaluation of left atrial function in patients with hypertrophic cardiomyopathy by real-time three-dimensional echocardiography and two-dimensional speckle tracking imaging

目的探讨实时三维超声心动图(RT-3DE)联合二维斑点追踪成像(2D-STI)在评价肥厚型心肌病(HCM)患者左房功能中的应用价值。方法选取肥厚型心肌病患者49例(HCM组)和健康志愿者33例(正常对照组),应用RT-3DE分别测量其左房最大容积(LAVmax)、左房最小容积(LAVmin)、左房收缩前容积(LAVpre),经体表面积矫正,计算出左房容积指数(LAVI)、左房每搏量(LASV)、左房射血分数(LAEF)、左房被动射血分数(LAPEF)和左房主动射血分数(LAAEF)。应用2D-STI获得左房各壁中间段长轴方向的心肌运动应变率曲线,测量左房各壁中间段左室收缩期峰值应变率(SRs)、左室舒张早期峰值应变率(SRe)和舒张晚期峰值应变率(SRa),计算其平均值(m SRs、m SRe、m SRa)。比较两组上述各参数的差异。采用Pearson相关分析法分析LAEF与mSRs、LAAEF与m SRa、LAPEF与mSRe间的相关性。结果与正常对照组比较,HCM组LAVImax、LAVImin、LAVIpre、LASV均增大,LAEF、LAPEF均减小,差异均有统计学意义(均P<0.05);LAAEF较正常对照组减小,但差异无统计学意义。与正常对照组比较,HCM组左房的房间隔、侧壁、前壁、后壁中间段的SRs及mSRs,房间隔、侧壁、前壁、下壁、后壁中间段的SRe、SRa及mSRe、m SRa均减小,差异均有统计学意义(均P<0.05)。mSRe与LAPEF、mSRa与LAAEF、mSRs与LAEF均呈正相关(r=0.608、0.314、0.396,均P<0.05)。结论 RT-3DE联合2D-STI技术可以准确评价HCM患者左房容积增大,左房辅泵功能、管道功能和储蓄功能的相互代偿作用减弱或消失,具有一定的临床应用价值。

Objective To explore the left atrial function in patients with hypertrophic cardiomyopathy （HCM）by real-time three-dimensional echocardiography （RT-3DE）and two-dimensional speckle tracking imaging （2D-STI） .Methods Forty-nine patients with HCM （HCM group）and 33 healthy volunteers （control group）were enrolled in this study.Left atrial maximalvolume （LAVmax）, left atrial minimal volume （LAVmin）, and left atrial presystolic volume （AVpre）were calculated by RT-3DE.Then the left atrial volume index （LAVI）was calculated by dividing the body surface area （BSA）, and left atrial stroke volume（LASV）, left atrial total ejection fraction （LAEF）, left atrial passive ejection fraction（LAPEF）, left atrial active ejection fraction（LAAEF）were calculated.Two-dimensional images were acquired from the apical four chamber view, two -chamber view andapical three-chamber view to retain images for offline analysis.The systolic, early and late diastolic peak strain rate（SRs, SRe,SRa）curves were acquired in each middle segment of left atrium （septal, lateral, anterior, inferior and posterior）by 2D-STI.Andthe average strain rate was calculated （mSRs, mSRe, mSRa）, then the differences of above parameters between the two groups werecompared.Finally, the correlation between LAEF and mSRs, LAAEF and mSRa, LAPEF and mSRe were analyzed by Pearsonanalysis, respectively.Results Compared with normal group, LAVImax, LAVImin, LAVIpre were increased in HCM group,meanwhile LAEF and LAPEF were decreased, the differences were statistically significant （all P〈0.05） .LAAEF was decreased in HCM group, but there was no difference compared with normal group.SRs of left atrial wall except inferior, mSRs, SRe of leftatrial wall, mSRe, SRa of left atrial wall and mSRa were decreased compared with normal group（all P〈0.05） .There werepositive correlation between mSRe and LAPEF, mSRa and LAAEF, mSRs and LAEF （r=0.608, 0.314, 0.396, all P〈0.05） .Conclusion RT-3DE combined with 2D-STI can accurately determine the left atrial volume in patients with HCM, and thecompensatory effects of left atrial pump function, conduit function and reservoir function are weakened or disappeared, which hasagood clinical application value.