从离体豚鼠心脏电场电势分布看瞬间心电向量的综合

Evaluation of resultant cardiac vector based on voltage distribution of electrocardial field around ex vivo guinea pig heart

目的探讨豚鼠离体心脏心电瞬间向量综合的可能性。方法采用50只豚鼠随机均分为2组,离体心脏分别浸入蒸馏水和生理盐水中,将参比点置于远离心电场源的零电位,记录3个平面左、右心室侧和与之垂直的前后壁侧,共4个方向上4个不同距离点的心电图。以4个方向各自记录的心电图QRS波形态和振幅来确定心电场电势分布,并以此判断瞬间心电向量的综合情况。结果每一平面4个方向上共16个点在两种电导率不同的溶液中都记录到以正波R(r)为主的心电图。心电场电势均呈一致向外的正相分布,未见心室左右壁或前后壁瞬间心电向量综合的结果。结论离体豚鼠心脏心电场电势分布表明瞬间心电向量综合的可能性存在疑问。

Objective To evaluate the possibility of resultant cardiac vector ofex vivo guinea pig heart. Methods ECGs were recorded in 4 directions on every plane, and in each direction 4 points at different distances from the anterior, posterior, right and left of isolated guinea pig ventricles immersed in normal saline and distilled water. Results Main upward waves of ECGs were recorded at all points in 4 directions at 3 levels in the two media. The voltage distribution of normal electrocardial field of the QRS wave was of all-round outward shape, which did not match the resultant cardiac vectors between the left and right and between the anterior and posterior ventricular walls. Conclusion There are some confusion and contradiction in the resultant cardiac vector based on the voltage distribution ofelectrocardial field around ex vivo guinea pig heart.