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Arterial Pressure

CARDIOVASCULAR PHYSIOLOGY

Cardiac output

I

Mean arterial pressure (MAP)

t

Peripheral

resistance

MAP = P,_rwsl +

( Piyit. PdlaU. >

3

ime

t

Arterial

compliance

J. Perkins o MSI

Figurę 4.14 Arterial Pressure-

The mean arłerial pressure <MAP) is ihe average pressure in the arteries averaged over limę. Il is determined by the < ardiar oulptil (CO) and ihe total peripheral resistance (TPR) as: MAP = CO x TPK. As described in Figurę 4.10, CO is determined by the stroke volume <SV> and hearl ratę <HR) as: CO = SV X HR. Blood volumc is an importanl determinant of SV. The sympathetic nervous system and a number of hormones (see Figurę 4.15) determme vascular resistance As a result of the heart's rhythmic pumping, the arterial pressure is pulsatile. The pulse pressure depends on the SV (large SV irw/eases the pulse prev surę) and the compli3nce of the artenal wali (decreased compliance mereases pulse pressure). With normal aging, compliance of the arterial wali iiKreasos and rosults in an inerease in the pulse pressure.

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