A text book of physiology . le distance from it, the lever will bedepressed during the systole. While at the spot of impulse itself thecontact of the ventricle is increased during systole, away from thespot the ventricle retires from the chest-wall (by the diminution ofits right-to-left diameter), and hence, by the mediastinal attachmentsof the pericardium, draws the chest-wall after it. Endo-cardiac pressure. In order to study more fully the changesgoiug on in the heart during the cardiac cycle, it becomes necessary U2 ENDO-CARDIAC PRESSURE. [Book i. to know something of what is taking place
A text book of physiology . le distance from it, the lever will bedepressed during the systole. While at the spot of impulse itself thecontact of the ventricle is increased during systole, away from thespot the ventricle retires from the chest-wall (by the diminution ofits right-to-left diameter), and hence, by the mediastinal attachmentsof the pericardium, draws the chest-wall after it. Endo-cardiac pressure. In order to study more fully the changesgoiug on in the heart during the cardiac cycle, it becomes necessary U2 ENDO-CARDIAC PRESSURE. [Book i. to know something of what is taking place in the interior of thecavities of the heart. Chauveau and Marey1, by introducing into theright auricle and ventricle respectively of the horse, through thejugular vein, small elastic bags, each communicating with a recordingtambour, were enabled to take simultaneous tracings of all thechanges of pressure occurring in the two cavities. These results areembodied in Fig. 28, of which the upper curve represents the changes I IE. Fig. 28. Teacing of the Vaeiations op Peessuee in the eight Aueicle and Ventei-cle, and of the Cardiac Impulse, in the Hoese. (Aftee Maeey.) To be readfrom left to right2. The tipper curve represents the variation of pressure within the auricle, themiddle curve the variations of pressure within the ventricle ; these two thereforeillustrate changes taking place in the interior of the heart. The lower curve representsthe variations of pressure transmitted to a lever outside the chest and constituting thecardiac impulse. A complete cardiac cycle, beginning at the close of the ventricularsystole, is comprised between the thick vertical lines I and II. The thin vertical linesrepresent tenths of a second, a, the gradual filling of the auricle and ventricle ; b, theauricular systole ; c, the ventricular systole ; d, oscillations of pressure, interpreted byMarey as caused by vibrations of the auriculo-ventricular valves ; e probably marks theclosing of the semiluna
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Keywords: ., bookcentury1800, bookdecade1870, bookpublisherlondo, bookyear1879
