Certain clinical features of cardiac disease / by G. A. Gibson.

  • Gibson George Alexander, 1854-1913.
Date:
1908
Catalogue details

Licence: In copyright

Credit: Certain clinical features of cardiac disease / by G. A. Gibson. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    [363] views. A heart which was shown to me the other day by Pro- fessor Adami and Dr. Klotz, of Montreal, concerning which the entire facts will be published by Professor Martin, in whose care the patient was, will certainly, to some extent, re- open the questions involved. It is probable that a block may take place higher up—at the sino-auricular junction. Hering, Wenckebach, and Hirsch- felder have already expressed their belief in such a pos- sibility, and one of the tracings which has just been shown, and which was previously published by Ritchie and myself, seems most easily explicable on the supposition that certain of the smaller waves which occur amongst, but do not accord with, the rhythm of the auricular impulses, are produced by [364] the sinus contraction. It is an interesting fact that the move- ments of the auricles in such cases are remarkably regular; when we find other waves appearing irregularly amongst them we must seek for some other cause, and this is most likely to be found in a pulsation of the sinus which has not been fol- lowed in the normal manner by the auricular systole. An abnormal increase in the rate of pulsation commonly known in modern times as tachycardia may apparently be produced by neurotic, toxic, or degenerative infiuences, but our comprehension of the subject is not yet so advanced as in the case of the conditions which have already been discussed. From the tracings which have been shoAvn, you will readily accept the statement that the increased rate is largely depend- ent upon the presence of premature systoles. Whether the origin of this change may be in part due to diminished infiu- ence of the inhibitory, or to increased activity of the accelera- tor nerves is uncertain, but we may assume in all such cases an increased production of the rhythmic stimulus at the sino- auricular junction of Keith, which must be regarded as the pace-maker for the whole heart, except in those cases where the impulses are blocked. There is, however, nothing now more certain than the fact that the ventricle may initiate a rhythm of its own, and one of the tracings which has just been brought before you shows most distinctly contractions of the ventricles in the total absence of all auricular movement.