CARDIAC OUTPUT IN MAN BY A DIRECT FICK METHOD: Effects of Posture, Venous Pressure Change, Atropine, And Adrenaline

The ear oximeter; its use clinically and in the determination of cardiac output

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Orthostatic factors in pulsus alternans

Ventricular alternans was present in three cardiac patients only in the erect or semierect position and disappeared with recumbency. The phenomenon which was regularly reproduced in the standing posture was prevented or minimized by exercise, digitalis, infusions of blood and norepinephrine and by application of external vascular support. Ventricular alternation in the supine patient was noted only after phlebotomy, or venous pooling combined with Valsalva maneuvers. The observations suggest that in the mechanism of this type of pulsus alternans there is an important peripheral hemodynamic factor which exerts its effect by changes in diastolic length of an injured ventricular muscle.

The effect on the human third heart sound of variations in the rate of filling of the heart

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Effect of blood and saline infusion on ventricular end diastolic pressure, stroke work, stroke volume and cardiac output in the open and closed chest dog

Left and right ventricular end diastolic pressure, stroke work, stroke volume, and cardiac output were measured in open and closed chest dogs infused with blood and/or saline. The methods employed permitted repeated determinations of these factors during short time intervals. For nonfatigued hearts in the open chest preparation point to point correlation of end diastolic pressure with the other three variables was very good, but in closed chest animals a number of non-correlations occurred. Sufficient variation was seen to indicate that factors other than those measured in this study will have to be known before cardiac performance in the intact animal can be fully assessed.