The irregular pulse : its value in prognosis ; Stokes-Adams disease : report of a case / by John Hay.

  • Hay, John, 1873-1959.
Date:
1906
Catalogue details

Licence: In copyright

Credit: The irregular pulse : its value in prognosis ; Stokes-Adams disease : report of a case / by John Hay. 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.

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    possesses five properties:—Excitability—the power to respond to a stimulus; conductivity—the power to conduct that stimulus from one point to another; tonicity; contractility; and, lastly, rhythmicity. This latter function is the one which mostly concerns us to-night. By rhythmicity we mean the power of the heart to produce rhythmically its own stimulus, independently altogether of the nervous system. The portions of the heart in which this power is most developed are chiefly the junction of the large veins with the auricles, to a less degree the junction of the auricles and ventricles, and the conus of each ventricle. We know that as a rule the stimulus arises where the large The upper tracing is from the neck, and shows a small wave (a) from the jugular vein and due to the systole of the right auricle preceding the large carotid wave. veins open into the auricles; but we must not forget that every portion of the heart muscle possesses in some degree the power to initiate a contraction by the production of a stimulus. It is the irregular action of the heart due to its response to abnormal stimuli which I wish to consider. Your hand is on your patient’s pulse; the wave is regular in force and frequency. As you keep your finger on the wrist, you notice that a beat is missed—the pulse intermits, but its rhythm is not interfered with ; the dropping of the beat has not spoilt your counting. Or instead of there being a complete pause, you are conscious of a small pulse wave which occurs earlier than you anticipated, and this is followed by a long
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