Finsen Alexandra Vanessa, Christensen Geir, Sjaastad Ivar
Institute for Experimental Medical Research, Ullevaal Univ. Hospital, Kirkeveien 166, N-0407 Oslo, Norway.
J Appl Physiol (1985). 2005 Feb;98(2):680-9. doi: 10.1152/japplphysiol.00924.2004. Epub 2004 Oct 8.
Our aim was to establish parameters describing systolic and diastolic function in mice after myocardial infarction (MI) that distinguish MI with pulmonary congestion from MI without congestion. Echocardiography, left ventricular (LV) catheterization, and infarct size measurements were performed on days 3, 5, 7, and 14 after ligation of the left coronary artery in C57BL/6 mice. Sham-operated mice were used as controls (Sham). MI mice with lung weight normalized to tibial length >125% of the average in the corresponding Sham group were considered to have pulmonary congestion (MIchf). MI mice with a smaller increase were called MI nonfailing (MInf). An infarct >40% of total LV circumference measured in two-dimensional long axis distinguished MIchf from MInf on both an average and an individual basis. Mean maximum rate of rise of LV pressure, LV fractional shortening, and posterior wall shortening velocity were significantly lower in MIchf compared with Sham at all time points and to MInf at 7 days. The diastolic parameters mitral flow deceleration velocity, LV end-diastolic pressure, and maximum rate of decline in LV pressure (LVdP/dtmin) discriminated the MIchf groups from Sham at all time points. Mitral flow deceleration velocity and LVdP/dtmin separated MIchf from MInf at 7 days. In addition to distinguishing all the groups on an average basis, left atrial diameter distinguished all MIchf animals from Sham and MInf. In conclusion, significantly increased left atrial diameter and infarct size >40% of total LV circumference may serve as major criteria for heart failure with pulmonary congestion after MI in mice.
我们的目标是建立描述心肌梗死（MI）后小鼠收缩和舒张功能的参数，以区分伴有肺充血的MI和无充血的MI。在C57BL/6小鼠左冠状动脉结扎后的第3、5、7和14天，进行了超声心动图、左心室（LV）导管插入术和梗死面积测量。假手术小鼠用作对照（假手术组）。肺重量与胫骨长度之比归一化后大于相应假手术组平均值125%的MI小鼠被认为有肺充血（MIchf）。增加幅度较小的MI小鼠称为非衰竭性MI（MInf）。在二维长轴上测量的梗死面积大于左心室总周长的40%，无论在平均值还是个体水平上，都能区分MIchf和MInf。与假手术组相比，MIchf在所有时间点的左心室压力平均最大上升速率、左心室缩短分数和后壁缩短速度均显著降低，与7天时的MInf相比也是如此。舒张参数二尖瓣血流减速速度、左心室舒张末期压力和左心室压力最大下降速率（LVdP/dtmin）在所有时间点都能区分MIchf组和假手术组。二尖瓣血流减速速度和LVdP/dtmin在7天时能区分MIchf和MInf。除了在平均水平上区分所有组外，左心房直径还能区分所有MIchf动物与假手术组和MInf。总之，左心房直径显著增加和梗死面积大于左心室总周长的40%可能是小鼠MI后伴有肺充血的心力衰竭的主要标准。
