瓣膜病围术期左心收缩功能的研究

Study of Left Ventricular Contractility During Valve Replacement

为用不受左室负荷影响的心肌收缩性能指标—收缩末弹性模量（Ｅｅｓ）—研究瓣膜病围术期左心功能，选择风心瓣膜病（ＲＨＤ）组１４例；先心对照（ＣＨＤ）组６例病人。以心外膜超声测左室容积、左室压，暂阻下腔静脉以绘出不同前负荷的左室压—容积环求得手术前后Ｅｅｓ。术中取部分病人乳头肌作电镜检查。结果示术前ＣＨＤ组Ｅｅｓ为０．６５７±０．１０１ｋＰａ／ｍｌ（４．９４±０．７６ｍｍＨｇ／ｍｌ），ＲＨＤ组０．２５４±０．０８９ｋＰａ／ｍｌ（１．９１±０．６７ｍｍＨｇ／ｍｌ）；术后ＣＨＤ组０．８１３±０．０８４ｋＰａ／ｍｌ（６．１１±０．６３ｍｍＨｇ／ｍｌ），ＲＨＤ组０．２７９±０．０５５ｋＰａ／ｍｌ（２．１０±０．４１ｍｍＨｇ／ｍｌ）。电镜显示ＲＨＤ组病人心肌纤维变性、坏死。结论：ＲＨＤ病人手术前后心肌收缩性能均减退且低于ＣＨＤ组（Ｐ＜０．０５）。

Aim:To study left ventricular contractility during valve replacement.Clinical material and method:14 patients with valvular disease(RHD group)and 6 patients with congenital heart disease(CHD)were studied.The loadindependent indexend systolic elastance(Ees) was used to study left ventricular contractility.Epicardial echocardiography was performed to measure the volume and pressure of left ventricule.According to obtained data,The left ventricular pressure volume loop was calculated and Ees was obtained.Result:Before surgery,Ees was 4.94±0.76mmHg/ml for CHD group and 1.91±0.67mmHg/ml for RHD group.After surgery,Ees was 6.11±1.63mmHg/ml for CHD group and 2.10±0.41mmHg/ml for RHD group.Ees was significantly lower in RHD group than that in CHD group pre and postoperatively.In RHD group,degeneration and necrosis of myofibrilla were found by ultrastructural study.Conclusion:Ees is a good and sensitive index in evaluating left ventricular contractility.Dysfunction of myocardial contractility may be attributed to changes of myocardial ultrastructure in RHD patients.