心肌梗塞范围与心功能关系的实验研究

本文报导大鼠心肌梗塞后第9天心功能与梗塞范围(IS)关系的研究结果。应用容量和压力负荷应激确定左室最大泵血和收缩能力。IS用周长法测定。在IS小于46％的大鼠,基础状态泵功能可保持正常。基础状态心功能指标与IS相关并不理想,而负荷状态的泵功能和收缩性指标在各IS组均明显异常,且与IS高度显著性相关,提示心脏储备功能指标能较可靠地反映心室功能受损程度和IS。IS越大,Frank—Starling机制在维持泵功能中的作用越重要。泵功能曲线和心指数增加速率在评定泵功能储备力和左室收缩性能、估计IS中有一定价值。

Experimental Study on the Relationship Between Myocardial Infarct Size and cardiac Function

The relationship between infarct size (IS)' and cardiac function 9 days after myocarial infarction was studied in rats. The maximum pump and contractile ability of the left ventricle (LV) were determined by volume loading stress or pressure loading stress, ISwasdetermined by measuring the circumferences of serial sections of LV.In rats with IS less than 46％,the pump function was normal in baseline state,and the baseline functional indices had unsatisfactory relations to IS.However,the pump and contractility indices obtained during stress were critically damaged in infarcted rats and there were strong and sifnificant relations between the indices reflecting the cardiac reserve and IS. The results suggested that cardiac reserve indices could reflect cardiac dysfunction and IS better than baseline indices.The larger the IS,the more important the Frank-Starling mechanism in the maintainance of pump function.The reserve of pump function curve and the increasing-rate of cardiac index during volume loading.