Chilson D A, Peigh P, Mahomed Y, Zipes D P
J Am Coll Cardiol. 1985 Feb;5(2 Pt 1):290-6. doi: 10.1016/s0735-1097(85)80049-8.
The purpose of this study was to test the hypothesis that vagal efferent nerves travel in the left ventricular subendocardium in a base to apex direction. Efferent vagal stimulation during constant background isoproterenol infusion prolonged left ventricular endocardial and epicardial effective refractory periods in a control state and after a left ventriculotomy performed while dogs were supported by cardiopulmonary bypass. After a 2 mm deep endocardial circumferential incision, efferent vagal stimulation still prolonged the effective refractory period at an endocardial site basal to the encircling endocardial incision, but no longer prolonged the effective refractory period at the endocardium or immediately overlying epicardium apical to the incision. Interpretation of these data suggests that efferent vagal fibers travel in the superficial subendocardium of the canine left ventricle in a base to apex direction, penetrating upward to innervate the epicardium. Conceivably, a lesion such as a subendocardial myocardial infarction could selectively interrupt efferent vagal innervation, leaving sympathetic innervation unopposed. This may be a source of some arrhythmias.
本研究的目的是验证迷走神经传出纤维沿左心室心内膜下层由心底向心尖走行这一假说。在持续输注异丙肾上腺素的背景下，迷走神经传出纤维刺激可延长对照组以及在体外循环支持下进行左心室切开术后犬的左心室心内膜和心外膜有效不应期。在心内膜进行2mm深的环形切口后，迷走神经传出纤维刺激仍可延长切口下方心内膜部位的有效不应期，但不再延长切口上方心内膜或紧邻的心外膜部位的有效不应期。对这些数据的解读表明，迷走神经传出纤维沿犬左心室心内膜下层由心底向心尖走行，并向上穿透以支配心外膜。可以想象，诸如心内膜下心肌梗死这样的病变可能会选择性地中断迷走神经传出纤维的支配，使交感神经支配失去拮抗。这可能是某些心律失常的一个原因。
