PhysiologyWeb Logo  Search
PhysiologyWeb Loading...

Glossary of Physiology Terms
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Search

There are 2 glossary search results for:   Aorta




Definition:
The large blood vessel (artery) that receives the output of the left ventricle of the heart. The aorta is the first and largest (in diameter) artery of the systemic circulation.

Following ventricular contraction (systole), hydrostatic pressure within the ventricle exceeds the pressure in the aorta, which forces blood out of the left ventricle, through the aortic semilunar valve, and into the aorta. As the ventricle relaxes during diastole, the pressure within the left ventricle drops to a level below that in the aorta. At this point, the aortic semilunar valve closes, which prevents the backflow of blood from the aorta to the left ventricle.



Definition:
Pulse pressure is defined as the arithmetic difference between the systolic pressure (the highest blood pressure) and the diastolic pressure (the lowest blood pressure) recorded at any point along the vascular bed. Therefore:

Pulse pressure = Systolic pressure - Diastolic pressure

Pulse pressure values can be reported at any point along the vasculature starting from the left ventricle and aorta all the way to the vena cava and the right atrium. As with systolic and diastolic pressure values, pulse pressure is typically reported in mm Hg (millimeters of mercury). A typical arterial pulse pressure is 40 mm Hg (120 - 80 = 40 mm Hg). This value decreases as one proceeds along the vascular bed from arteries to arterioles, capillaries, venules, and veins. The most significant drop occurs along the arterioles.

See also:
Mean Arterial Pressure Calculator









Posted: Sunday, March 31, 2013
Last updated: Friday, August 28, 2015