Cardiovascular
I.	Heart
A.	Location
B.	Function – pump blood to cells; maintenance of perfusion
C.	Structure
1.	chambers
2.	valves
3.	musculature
a.	layers 
Frank Starling Law – helps to adjust to demands of the body
b.	unique properties of cardiac cells
1)	excitability (respond to stimulus)
2)	conductivity (speed  via intercalated discs)
3)	automaticity (generate own stimulus)
4)	contractility

c.	 sensitivity to catecholamines (epi, norepi, dopamine)
D.	Conduction System
1.	brain controls via autonomic nervous system, hormones of endocrine 
system, and the heart tissue
2.	Structures

E.	Regulation of function
1.	 sensitivity to catecholamines
a.	enhance efficiency of cardiac function
2.	baroreceptors
a.	sense changes is pressure (within heart, vessels)
3.	chemoreceptors
a.	sense changes in chemical composition of blood
4.	via
a.	chronotropic = rate
b.	dromotropic = conduction
c.	inotropic = strength of contraction
5.	sympathetic nervous system
a.	+ chronotropic, inotropic
b.	norepi  causes vasoconstriction
c.	epi  causes chronotropic, inotropic, dromotropic
6.	electrolytes (responsible for initiating, conducting impulses)
electrical potential = polarized state, resting net - charge
a.	Na+ > outside (more +) (movement into = depolarization)
b.	K+ > inside (less +)
c.	Ca++ slow influx propagates electrical current, leaks out to aid in muscle contraction
d.	Repolarization = return to net – charge (K flows out, Na actively pumped out; K actively pumped in)
e.	Refractory period
a.	absolute (high ion concentration will not accept stimulus)
b.	relative (stronger than normal stimulus could trigger)
F.	ECG
G.	Cardiac Cycle
Def: repetitive pumping process beginning with onset one muscle contraction, ending with beginning of next pressure changes cause blood to move
1.	systole – ventricular contraction
2.	diastole – ventricular relaxation
a.	BP as a function of
3.	afterload
4.	cardiac output – amount of blood pumped/min (L/min)
CO = SV x HR