Hochman J S, Bulkley B H
Am J Cardiol. 1982 Jul;50(1):83-8. doi: 10.1016/0002-9149(82)90012-1.
Left ventricular aneurysms, convex protrusions at sites of transmural scar, are clinically recognized late after myocardial infarction because of their hemodynamic or arrhythmic complications. Whether aneurysms develop from dilation of freshly infarcted myocardium early after myocardial infarction or from late dilation of scar is not known. To investigate this question, the time course of changes in shape of the left ventricle early and late after myocardial infarction was studied. One hundred forty-one myocardial infarcts were produced in rats by coronary ligation, and the animals were killed at time periods of up to 6 weeks. True aneurysms developed as early as 2 weeks and only in rats with a transmural infarct. The percent of rats that manifested "aneurysmal shape changes" (defined as a protrusion of the full thickness of the left ventricular wall) increased from day 1 to day 5, but did not change significantly thereafter. The extent of left ventricular dilation in hearts with early aneurysmal shape changes did not progress significantly up to day 42. Accordingly, in the rat, regional aneurysmal shape alterations are due not to late dilation of scare tissue, but rather to "expansion" of freshly necrotic myocardium within the first 5 days of infarction. Thus, early changes in shape appear to determine late aneurysm formation.
左心室室壁瘤是透壁性瘢痕部位的向外膨凸，由于其血流动力学或心律失常并发症，在心肌梗死后较晚才被临床识别。室壁瘤是在心肌梗死后早期由新鲜梗死心肌的扩张发展而来，还是由瘢痕的晚期扩张发展而来尚不清楚。为了研究这个问题，我们研究了心肌梗死后早期和晚期左心室形状变化的时间进程。通过冠状动脉结扎在大鼠身上制造了141个心肌梗死模型，并在长达6周的时间段内处死动物。真性室壁瘤最早在2周时出现，且仅在透壁性梗死的大鼠中出现。表现出“瘤样形状改变”（定义为左心室壁全层的突出）的大鼠百分比从第1天到第5天增加，但此后没有显著变化。早期有瘤样形状改变的心脏中左心室扩张的程度在第42天之前没有显著进展。因此，在大鼠中，局部瘤样形状改变不是由于瘢痕组织的晚期扩张，而是由于梗死最初5天内新鲜坏死心肌的“扩张”。因此，早期形状变化似乎决定了晚期室壁瘤的形成。
