A manual of the diseases of the heart : their pathology, diagnosis, prognosis and treatment / by Robert Hunter Semple.

  • Semple, R. H. (Robert Hunter)
Date:
1875
Catalogue details

Licence: Public Domain Mark

Credit: A manual of the diseases of the heart : their pathology, diagnosis, prognosis and treatment / by Robert Hunter Semple. Source: Wellcome Collection.

Provider: This material has been provided by University of Bristol Library. The original may be consulted at University of Bristol Library.

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    explained on the supposition that under ordinary circumstances the sensory nerve-filaments in passing through the sympathetic ganglia are deadened in their function by the influence of the latter; while, in morbid conditions, it may be conceived that the sympathetic ganglia are paralysed, and the sensation of the ordinary nerves is thereby allowed to develope itself. In connection with the physiology of the heart, enough has now been adduced to show why its healthy functions are performed without the control or influence of the will, and why the organ itself is desti- tute of ordinary sensibihty. The painful affections of the heart may receive some explanation from the suggestions just thrown out, and the effect of medicines may perhaps be explained by reference to its nerve-supply. Such explanations will be subsequently offered in the course of this work. As it is not my intention to give an historical account of the various theories entertained as to the movements of the heart, and the re- spective periods of their occurrence, I pass over the views expressed on this subject by Haller, Harvey, and Laeunec, only observing that the first physiologist failed to notice any period of repose between the contractions of the auricles and ventricles, or at any rate considered such repose only as an occasional occurrence j-*^ that the second showed that the contraction of the heart constituted only one move- ment, in which both auricles and ventricles take part, and that during the interval between each contraction and its successor the heart is absolutely at rest f and that the third, Laennec, agreed with Harvey in thinking that the heart, far from being in a constant state of movement, presents alternate periods of action and repose, like some other muscles of the animal economy, as the diaphragm and the intercostal muscles.^ Laennec, in fact, roughly calculated, (on the * Post auricularum coustrict,ionem,'^celerrime in calido et sano animale, ali- quanto lentius in frigido et langueute, et nonnunquam satis maguo etiam in calidis tempusculo interposito sequitur veutiiculorum coutractio (Haller, ' Elem. Physiologise,' torn. I, lib. iv, sect. 4). The word nonnunquam seeuis to imply that the interval of rest is not a constant event. ' Primum sese contrahit auricula et in ilia contractione sanguinem contentum in ventriculum cordis conjicit; quo repleto, cor sese erigit, coutinuo omues nervos tendit, contrahit ventriculos, et pulsum I'acit. . . . Isti duo motus, auricularum unus, alter ventriculoruiii, ita per consecutionem fiunt, servata qtiasi harniouia ct rhylhmo, ut ambo sinuil fiaut et unicus tantum motus ap- paret. Harvey, ' Opera omnia,' 1766, p. 33. 3 Laennec, vol iii, p. 53.