二维斑点追踪技术对肥厚型梗阻性心肌病患者化学消融术术前及术后左心房功能的评估

Assessment of left atrial function in patients with hypertrophic obstructive cardiomyopathy before and one year after alcohol septal ablation by two dimensional speckle tracking echocardiography

目的应用二维斑点追踪技术对肥厚型梗阻性心肌病(HOCM)患者经皮经冠状动脉室间隔化学消融术(PTSMA)术前及术后1年左心房功能的评估。方法选取2012年11月至2014年12月在浙江大学医学院附属邵逸夫医院行PTSMA手术HOCM患者31例,其中,男性13例,女性18例,年龄22~71岁,平均年龄(51±13)岁。心功能NYHA分级为(2.6±0.7)级。如果靶区域超声造影剂显示正常,通过球囊中心腔向导管腔内缓慢推注无水乙醇增大剂量3.0 ml,保持球囊充盈10 min。以LVOTG下降≥50%作为手术成功的标准。于室间隔化学消融术前及术后1年接受超声心动图检查。测量包括左心室流出道压差(LVOTG),二尖瓣关闭不全(MR)的程度,左心房前后径,左心室射血分数(LVEF)和组织多普勒(TDI)测定二尖瓣环舒张早期峰值速度e'(取室间隔和侧壁)。采用二维斑点追踪技术自动追踪左心房壁,并获取左心房容积曲线,获得左心房最大容积(LAVmax)、左心房最小容积(LAVmin)及左心房收缩前容积(LAVpre-a)。计算出左心房储备功能包括左心房充盈扩张分数(LAEI)及左心房舒张期排空分数(LADEI)、左心房管道功能包括左心房被动排空比(PE)及被动排空指数(PEI)、左心房泵功能包括左心房主动排空比(AE)及主动排空指数(AEI)。PTSMA术前及术后患者心功能NYHA分级、超声心动图测量结果、左心房容积参数之间的比较采用配对t检验。结果 PTSMA术后1年与术前比较,LVOTG、MR的程度、左心房前后径、E/侧壁e'比值、二尖瓣环室间隔e'均下降,差异均有统计学意义[(35±26)mmHg vs(74±35)mmHg(1 mmHg=0.133 k Pa)、0.93±0.35 vs 2.27±0.73、(40±6)mm vs(45±6)mm、12.6±3.8 vs14.6±4.6、(4.3±1.1)cm/s vs(5.0±1.3)cm/s,t=6.55、4.78、2.60、2.84、2.59,P均<0.05];心功能NYHA分级、二尖瓣环侧壁e'、E/室间隔e'比值增加,差异均有统计学意义[1.4±0.5 vs 2.6±0.7、(6.9±2.3)cm/s vs(5.8±1.7)cm/s、20.2±7.1 vs 17.0±5.2,t=-3.32、-2.67、-2.93,P均<0.05]。消融术后1年与术前比较,LAVImax,LAVImin、LAVIpre-a、AE、AEI(%)下降[(32.7±7.1)ml/m^2vs(38.9±9.3)ml/m^2、(16.3±4.4)ml/m^2 vs(20.7±5.5)ml/m^2、(23.1±5.7)ml/m^2 vs(30.5±7.0)ml/m^2、(41.5±8.7)%vs(53.8±10.4)%、(29.4±3.9)%vs(32.1±4.6)%],差异均有统计学意义(t=3.65、3.11、3.38、3.92、2.17,P均<0.05);LAEI(%)、LADEI(%)、PE(%)、PEI(%)增加[(100.1±19.3)%vs(87.9±14.7)%、(50.2±9.8)%vs(46.7±9.1)%、(58.5±11.8)%vs(46.1±9.1)%、(26.9±5.2)%vs(21.6±4.8)%],差异均有统计学意义(t=-2.82、-2.33、-3.89、-2.74,P均<0.05)。结论 HOCM患者室间隔消融术后1年左心房的储备及管道功能得到改善,而左心房泵功能及主动收缩耗能下降。

Objective To assess left atrial（LA） function by two dimensional speckle tracking echocardiography（2DSTE） in patients with hypertrophic obstructive cardiomyopathy（HOCM） before and one year after percutaneous transluminal septal myocardial ablation（PTSMA）.Methods The study included 31 patients with HOCM who underwent PTSMA performed between November 2012 and December 2014 in Sir Run Run Shaw Hospital.Mean age was 51±13 years,and 13 patients were men,18 patients were women.New York Heart Association class was 2.6±0.7 at baseline.If the target region was correctly marked by the injection of the echo contrast agent,ethanol was slowly（0.5 ml/min） injected to a maximum of 3 ml.Ten minutes after the injection of ethanol,the balloon was deflated.A successful procedure was defined as a ≥ 50% reduction in the LV outflow tract peak systolic gradient compared to baseline level.Each patient with HOCM had a complete two-dimensional transthoracic echocardiography assessment before and one year after the PTSMA.The measurements included basal septal thickness,left ventricular outflow tract（LVOT） gradient,mitral regurgitation（MR） grade,left atrial dimensions,left ventricular（LV） ejection fraction and tissue Doppler parameters of lateral mitral annular e＇ and septal mitral annular e＇.The LA wall was tracked on a frame-by-frame basis using 2D-STE,and LA volume waveforms were generated.The maximum LA volume（LAVmax）,minimal LA volume（LAVmin）,and the LA volume before atrial contraction（LAVpre-a） were measured.The LA reservoir function was calculated as left atrial expansion index（LAEI） and left atrial diastolic emptying index（LADEI）.The LA conduit function was calculated as the passive emptying percentage of total emptying（PE） and the passive emptying index（PEI）.The LA booster function was calculated as the active emptying percentage of total emptying（AE） and the active emptying index（AEI）.The comparisons between patient New York Heart Association class,echocardiography and LA function parameter before and after PTSMA were conducted by paired t test.Results Compared with pre-operative values,LVOTG,MR grade,LA end-diastolic size,E/lateral e＇ ratio,septal mitral annular e＇ decreased in patients one year after the PTSMA [（35±26） mm Hg vs（74±35） mm Hg,0.93±0.35 vs 2.27±0.73,（40±6） mm vs（45±6） mm,12.6±3.8 vs 14.6±4.6,（4.3±1.1） cm/s vs（5.0±1.3） cm/s],whereas New York Heart Association class,Lateral mitral annular e＇,E/septal e＇ ratio [1.4±0.5 vs 2.6±0.7,（6.9±2.3） cm/s vs（5.8±1.7） cm/s,20.2±7.1 vs 17.0±5.2] increased（t=6.55,4.78,2.60,2.84,2.59,-3.32,-2.67,-2.93,all P〈0.05）.Compared with pre-operative values,LAVImax,LAVImin,LAVIpre-a,AE,AEI（%） decreased in patients one year after the PTSMA [（32.7±7.1） ml/m^2 vs（38.9±9.3） ml/m^2,（16.3±4.4） ml/m^2 vs（20.7±5.5） ml/m^2,（2 3.1±5.7） m l/m^2 vs（3 0.5±7.0） ml/m^2,（4 1.5±8.7） % vs（5 3.8±1 0.4） %,（2 9.4±3.9） % vs（32.1±4.6）%],（t=3.65,3.11,3.38,3.92,2.17,all P〈0.05）;whereas the LAEI（%）,LADEI（%）,PE（%）,PEI（%）[（100.1±19.3）% vs（87.9±14.7）%,（50.2±9.8）% vs（46.7±9.1） %,（58.5±11.8） % vs（46.1±9.1） %,（26.9±5.2）% vs（21.6±4.8）%] increased（t=-2.82,-2.33,-3.89,-2.74,all P〈0.05）.Conclusions The study showed the improvement in LA reservoir and conduit function,while the reduction in LA booster pump function in patients one year after PTSMA.