心肌梗死面积对心肌梗死患者左心房功能改变的影响研究

Study of Relationship between Infarct Area and Left Atrial Function Changes in Patients with Myocardial Infarction

目的评价心肌梗死患者梗死面积大小对左心房功能改变的影响,探讨影响左心房功能的主要因素。方法选择62例心肌梗死患者及28例健康志愿者(对照组)为研究对象。根据美国超声心动图学会(ASE)推荐的16节段法(室壁运动异常阶段数≥4为大面积梗死,<4为小面积梗死),将62例心肌梗死患者分为小面积梗死组(A组,32例)和大面积梗死组(B组,30例)。A、B组及对照组受检者均进行超声心动图检查,比较3组受检者左心房的功能,评价不同梗死面积对左心房功能的影响;分析室壁运动状态〔以室壁运动指数(WMSI)表示〕与左心房功能参数间的相关性;以心肌梗死患者左心房开始收缩时容积指数(VpreI)为因变量,采用多元逐步回归分析心肌梗死后影响左心房功能的主要因素。结果 A、B组患者左心房最大容积指数(VmaxI)、左心房最小容积指数(VminI)、VpreI、左心房主动排空容积指数(AEVI)、左心房射血力指数(EFI)显著高于对照组,且B组上述参数亦显著高于A组,差异有统计学意义(P<0.05);A、B组患者左心房被动排空分数(PEF)及膨胀指数(AEI)显著低于对照组,且B组患者上述两指标亦显著低于A组,差异有统计学意义(P<0.05)。WMSI与VmaxI、VminI、VpreI、AEVI及AEI相关(r值分别为0.758、0.798、0.697、0.529和-0.717,P均<0.01)。以VpreI为因变量,进入回归方程的变量有WMSI、左心室舒张末内径(LVDd)及E/A。结论随着心肌梗死面积的增大,心肌梗死患者的左心房重构加重,左心房"管道"功能及"储器"功能减低,左心房"助力泵"功能增加。室壁运动状态、左心室重构及左心室舒张功能是影响左心房功能的主要因素。

Objective To evaluate the effect of infarct area size on left atrial function changes in patients with myocardial infarction,and to explore major factors affecting the left atrial function.Methods 62 patients with myocardial infarction were divided into large area group（30 cases） and small area group（32 cases）（in accordance with ASE recommended 16-segment method,a large area ＇4 above,a small area＇ 4 below）,and 28 healthy people were selected as normal control group.The left atrial function was compared,the effect of different infarct size on left atrial function was evaluated;the wall motion state（as expressed by wall motion index WMSI） and the correlation between left atrial function and parameters were analyzed.Taking the volume index at the contraction of left atrial as dependent variable,analyze the major factors affecting left atrial after myocardial infarction by stepwise regression.Results Maximum left atrial volume index（VmaxI）,left atrial minimal volume index（Vmi-nI）,VpreI,left atrial active emptying volume index（AEVI）,left atrial ejection force index（EFI） in A and B group were significantly higher than that in control group,and the above indexes were significantly higher in B group than that in A group（P 0.05）.Left atrial passive emptying fraction（PEF） and expansion index（AEI） in A and B group were significantly higher than that in control group,and the two above indexes were significantly higher in B group than that in A group（P 0.05）.the control group,A group,B group in turn reduced（P 0.05）;WMSI and VmaxI,VminI,VpreI,AEVI and AEI had excellent correlation（the value of r were 0.758,0.798,0.697,0.529 and-0.717 respectively,P all 0.01）.Taking VpreI as dependent variable,variables that entered into the regression equation were WMSI,left ventricular end-diastolic diameter（LVDd） and E/A.Conclusion With the increase of infarct area,left atrial remodels heavier,left atrial ＇channel＇ function and ＇storage device＇ function reduce,while the left atrial ＇booster pump＇ function increases.Wall motion status,left ventricular remodeling and left ventricular diastolic function are the main factors affecting the function of left atrial.