Papp L, Alló G, Szabó Z, Juhász-Nagy A
Acta Morphol Hung. 1985;33(1-2):123-42.
Acute ischaemia of the left ventricular apical region has been produced by occluding for 60 min the upper mid-portion of the left anterior descending (LAD) coronary artery in the exposed heart of anaesthetized dogs. The decrease of the blood supply to this region was associated with characteristic morphologic patterns of the subepicardial temperature distribution which has been visualized with the aid of telethermography using an AGA 750 thermovision equipment. The thermographic cardiac images recorded during the progressive development and the restitution of the ischaemic events were evaluated with a new computer-assisted method developed by the authors and the results were described in composite histograms. The validity of the assumption that subepicardial cooling and warming in a particular region could be ascribed to a decrease and increase, respectively, of local flow, was substantiated by computerized simulation of myocardial heat transfer. In both the intact and the ischaemic (collateral-dependent) portions of the heart the issues of the quantitative evaluation of experimental data were indicative of important dynamic factors that elicit, depending upon some partially known individual characteristics, either compensatory adjustments in the entire myocardium (generalized vasodilation) or a demarcation of the infarct (selective flow decrease). Proofs obtained in additional experiments by administering exogenous catecholamines suggest that ischaemically transformed adrenoceptor mechanisms may play a significant role in the latter process. It was concluded that the quantitative thermographic technique developed by the authors is suitable, due to its considerable temporal and spatial resolution, for concurrent analysis of the time course and the gross morphologic details of cardiac ischaemia in vivo.
在麻醉犬的开胸心脏中，通过阻断左前降支（LAD）冠状动脉上中部60分钟，造成左心室心尖区域急性缺血。该区域血液供应的减少与心外膜下温度分布的特征性形态模式相关，借助AGA 750热成像设备的远红外热成像技术可观察到这种模式。利用作者开发的一种新的计算机辅助方法，对缺血事件进展和恢复过程中记录的心脏热成像图像进行评估，并将结果绘制成复合直方图。通过心肌热传递的计算机模拟，证实了特定区域心外膜下冷却和升温分别可归因于局部血流减少和增加这一假设的正确性。在心脏的完整部分和缺血（依赖侧支循环）部分，实验数据定量评估的结果都表明存在重要的动态因素，这些因素根据一些部分已知的个体特征，要么引发整个心肌的代偿性调整（全身性血管舒张），要么导致梗死区域的界定（选择性血流减少）。通过给予外源性儿茶酚胺进行的额外实验获得的证据表明，缺血转化的肾上腺素能受体机制可能在后者过程中起重要作用。得出的结论是，作者开发的定量热成像技术，由于其具有相当高的时间和空间分辨率，适用于同时分析体内心脏缺血的时间进程和大体形态细节。
