The auriculo‐ventricular bundle of the human heart

摘要

In a letter contributed to THE LANCET one of us described the initial difficulty in finding and displaying the muscular bundle which unites the auricles and ventricles and which is now regarded as the sole pathway for the passage of the auricular wave of contraction to the ventricles. Since that letter was written we have examined over 130 human hearts and although we failed to find the bundle in some of the earlier specimens we are now confident that our failure was due to our ignorance of certain variations which may occur in its position and relationships. We are now convinced that it is an absolutely constant structure and in the properly prepared heart is big enough to be found and dissected out by knife and forceps alone; its finer structure and exact connexions require the preparation of serial microscopic sections. Through the kindness of Mr. Frank Beddard, F.R.S., prosector to the Zoological Society, and of Principal J. Y. Mackay of University College, Dundee, we have had opportunities of examining the hearts of nearly every mammalian order; in all the auriculo‐ventricular bundle is present, in all it has the same position, the same connexions and distribution. We have found it in the heart of the young human foetus in the position and form described by W. His, jun., so long ago as 1893. In seven out of nine malformed human hearts we were able to dissect out the bundle by means of knife and forceps. In a case of heart‐block, described by Dr. John Hay, we found that the bundle was partially obliterated at the point at which it perforates the central fibrous body of the heart. In another case of heart‐block (Dr. Otto F. F. GrüUnbaum's) we found the bundle involved within a gumms of the septum.