Heart-beat and pulse-wave / by C.S. Roy and J.G. Adami.

  • Roy, Charles Smart, 1854-1897.
Date:
1890
Catalogue details

Licence: Public Domain Mark

Credit: Heart-beat and pulse-wave / by C.S. Roy and J.G. Adami. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    64/94
    to tli« HEART-BEAT AND PULSE-WAVE. BY C, S. ROY, M.D. F.R.S., Professor of Pathology, AND J. G. ADAMI, M.A., MB,, Demonstrator of Pathology, in the University of CamhrOge. [From the Oavibridge Pathological Laboratory.] SECTION VI.—Continued. THE NORMAL PULSE-WAVE. We have now to consider what is the meaning of each of the chief features of the normal pulse-curve. With regard, first of all, to the up-stroke : it is of course due to the correspondingly rapid rise of pressure in the artery, which commences at the root of the aorta at the moment of opening of the aortic valve. This is opened when the pressure within the ventricle exceeds that within the aorta. If the mean pressure in thj aorta be high, the valve opens at a later period of the cardiac systole than would otherwise be the case, and vice versd; on the other hand, the quantity of blood in the heart at the end of diastole, and the force of the ventricular contraction, influence the rapidity with which the intraventricular pressure is raised during the earlier part of systole, and in this way also may cause a change in the time-relation between the commencement of the ventricular contraction and the opening of the valve. It must be kept in mind then that at the root of the aorta the beginning of the pulse-wave does not bear a constant relation in time to the beginning of the ventricular systole, a fact which is of considerable importance in influencing the form of the pulse-wave. bj measuring the Ji^tai drawDbjtlierecoKliDg ment of tk up-stroke ilso m[\ the rapidity lliis (juestion vie im meiiiiliig of tk supei of tbese. I'- is of special im] spijgmoffrapliic curv( '^■n tie ventricle, ^y^simuitaneou , ^^^fdiuQiis,