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Venous blood with an oxygen concentration of 15 mL/100 mL would therefore lead to typical values of the a-vO 2 diff at rest of around 5 mL/100 mL. During intense exercise, however, the a-vO 2 diff can increase to as much as 16 mL/100 mL due to the working muscles extracting far more oxygen from the blood than they do at rest. [citation needed]
In "retrograde" flow, the flow would reverse (e.g. veins flow away from heart or arteries flow towards the heart). However, "retrograde" flow can be both abnormal or normal. For example, in portal hypertension, there is an abnormal portal venous flow where it flows away from the liver (hepatofugal flow) instead of the normal flow towards liver ...
Note that, for cardiac function curve, "central venous pressure" is the independent variable and "systemic flow" is the dependent variable; for vascular function curve, the opposite is true. It shows a steep relationship at relatively low filling pressures and a plateau, where further stretch is not possible and so increases in pressure have ...
The pumping action of the heart generates pulsatile blood flow, which is conducted into the arteries, across the micro-circulation and eventually, back via the venous system to the heart. During each heartbeat, systemic arterial blood pressure varies between a maximum and a minimum pressure. [33]
Doppler measurements using Doppler effect can show the direction of the blood flow and its relative velocity, and color Doppler is the provision of color to help interpret the image, showing, for example, the blood flow toward the probe in one color and that flowing away in another. While the equipment itself is costly, the procedure is not.
When the arteries are healthy, they are capable of autoregulating themselves to maintain the coronary blood flow at levels appropriate to the needs of the heart muscle. The relatively narrow coronary arteries are commonly affected by atherosclerosis and can become blocked, causing angina or a heart attack .
Blood pressure. Aortic pressure; Ventricular pressure; Atrial pressure; Ventricular volume; Electrocardiogram; Arterial flow (optional) Heart sounds (optional) The Wiggers diagram clearly illustrates the coordinated variation of these values as the heart beats, assisting one in understanding the entire cardiac cycle. [1]
Doppler echocardiography is a procedure that uses Doppler ultrasonography to examine the heart. [1] An echocardiogram uses high frequency sound waves to create an image of the heart while the use of Doppler technology allows determination of the speed and direction of blood flow by utilizing the Doppler effect.