Nozawa E, Kanashiro R M, Murad N, Carvalho A C C, Cravo S L D, Campos O, Tucci P J F, Moises V A
Disciplina de Fisiologia Cardiovascular, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
Braz J Med Biol Res. 2006 May;39(5):687-95. doi: 10.1590/s0100-879x2006000500016. Epub 2006 Apr 20.
Although echocardiography has been used in rats, few studies have determined its efficacy for estimating myocardial infarct size. Our objective was to estimate the myocardial infarct size, and to evaluate anatomic and functional variables of the left ventricle. Myocardial infarction was produced in 43 female Wistar rats by ligature of the left coronary artery. Echocardiography was performed 5 weeks later to measure left ventricular diameter and transverse area (mean of 3 transverse planes), infarct size (percentage of the arc with infarct on 3 transverse planes), systolic function by the change in fractional area, and diastolic function by mitral inflow parameters. The histologic measurement of myocardial infarction size was similar to the echocardiographic method. Myocardial infarct size ranged from 4.8 to 66.6% when determined by histology and from 5 to 69.8% when determined by echocardiography, with good correlation (r = 0.88; P < 0.05; Pearson correlation coefficient). Left ventricular diameter and mean diastolic transverse area correlated with myocardial infarct size by histology (r = 0.57 and r = 0.78; P < 0.0005). The fractional area change ranged from 28.5 +/- 5.6 (large-size myocardial infarction) to 53.1 +/- 1.5% (control) and correlated with myocardial infarct size by echocardiography (r = -0.87; P < 0.00001) and histology (r = -0.78; P < 00001). The E/A wave ratio of mitral inflow velocity for animals with large-size myocardial infarction (5.6 +/- 2.7) was significantly higher than for all others (control: 1.9 +/- 0.1; small-size myocardial infarction: 1.9 +/- 0.4; moderate-size myocardial infarction: 2.8 +/- 2.3). There was good agreement between echocardiographic and histologic estimates of myocardial infarct size in rats.
虽然超声心动图已用于大鼠研究，但很少有研究确定其在估计心肌梗死面积方面的有效性。我们的目的是估计心肌梗死面积，并评估左心室的解剖和功能变量。通过结扎左冠状动脉，在43只雌性Wistar大鼠中制造心肌梗死。5周后进行超声心动图检查，测量左心室直径和横截面积（3个横切面的平均值）、梗死面积（3个横切面上梗死弧的百分比）、通过面积分数变化评估收缩功能，以及通过二尖瓣血流参数评估舒张功能。心肌梗死面积的组织学测量与超声心动图方法相似。通过组织学测定的心肌梗死面积范围为4.8%至66.6%，通过超声心动图测定的范围为5%至69.8%，两者具有良好的相关性（r = 0.88；P < 0.05；Pearson相关系数）。左心室直径和平均舒张期横截面积与组织学测定的心肌梗死面积相关（r = 0.57和r = 0.78；P < 0.0005）。面积分数变化范围为28.5±5.6（大面积心肌梗死）至53.1±1.5%（对照组），与超声心动图测定的心肌梗死面积相关（r = -0.87；P < 0.00001），也与组织学测定相关（r = -0.78；P < 0.00001）。大面积心肌梗死动物的二尖瓣流入速度E/A波比值（5.6±2.7）显著高于其他所有动物（对照组：1.9±0.1；小面积心肌梗死：1.9±0.4；中面积心肌梗死：2.8±2.3）。大鼠心肌梗死面积的超声心动图和组织学估计之间具有良好的一致性。
