Anatomy & Physiology 2 - Heart & Blood Vessels - Exam 3

1. • Serous Pericardium
– Parietal(internal surface)
– Visceral(epicardium)ext
• Left Atrium
– 4 pulm veins transport
oxygenated blood from
lungs to heart
• Coronary Circulation
– Blood carried to
capillaries in
myocardium by coronary
arteries
• Angina pectoris
– Transient spasms of
coronary artery
• Valvular stenosis of
coronary artery may
increase pressure of left
ventricle
• Intrinsic conduction sys
– SA node, AV node, AV
bundle, R/L bundle
branches, Purkinje fiber
• Ectopic Focus
– If AV node depolarzes
quicker than SA the AV
may be come pacemaker
• If AV damaged=heart
block

2. • P-Wave
– atrial depolarization –
occurs just before &
indicates muscular phase
of atrial depolarization
• QRS Wave
– Ventricular depolarizat
• T Wave
– Ventricular repolarizati
• Q-T Interval
– Vent depolarization thru
vent repolarization
• Capillaries
– Greatest cross-sectional
– Slowest blood velocity
• ↑ R wave - ↑ventricle
• Cardiac cycle
– Tricuspid closed during
ventricular systole
– 2nd heart sound end of
ventricular ejection phs
– AV valves closed during
ventricular wall contract
– Blood flows through
atria & open AV valves
during ventriuclar filling
• Stroke Volume Int Fact
– Preload(intrinsic)
– Contractility
– Afterload

3. • If cardiac output low
– ↑ EDV/SV/force of
contractility
• Norepiniphrine
threshold kicks in
quicker
• Heart rate int fact
– Ions, hormones,
epinephrine,
norephinephrine
• Age effects on heart
– Sclerosis, ↓ card . Res.,
fibrosis, atherosclerosis
• Veins
– Thinner walls/large
lumen/valves
– Deoxygenated bld to hrt
• Arteries
– Oxygenated bld from hrt
• Tunics
– Tunica intima(endothel)
– Tunica media(BP)
– Tunica Externa
• Renin, angiotensin II,
ADH all retain water
with dehydration

4. • Venous return
– Resp pump – pressure
changes during
breathing – more blood
towards hrt by squeezing
abd. Veins as thoracic
veins exp
– Musc pump- contraction
of skeletal muscles
– Sympathetic nervous
syst – vasoconstriction
• Aldosterone ↑ BP
• Vasodilators
– Nitric oxide/ANP/alcohol
• Intrinsic control mech
– Metabolic/chemical
– Myogenic/physical
• Precapillary sphincter
– Regulate blood from
arterioles to post
capillary venule
• Duration of cardiac cyc
–
60
𝐵𝑃𝑀
• Normal Stroke Volume
• EDV – ESV = SV
–
120𝑚𝑙
𝑏𝑒𝑎𝑡
−
50𝑚𝑙
𝑏𝑒𝑎𝑡
=
70𝑚𝑙
𝑏𝑒𝑎𝑡

5. • Cardiac Output
– Heart Rate X Stroke Volume = Cardiac Output(HR X SV =
CO)
–
75 𝑏𝑒𝑎𝑡𝑠
𝑚𝑖𝑛
×
70 𝑚𝑙
𝑏𝑒𝑎𝑡
=
5250 𝑚𝑙
𝑚𝑖𝑛
=
5.25 𝐿
𝑚𝑖𝑛
• Pulse pressure is the difference between diastolic &
systolic
–
𝑆
𝐷
=
120
80
= 120 − 80 = 40
• How to calculate MAP(Mean Arterial Pressure)
– Example: BP =
120
80
– Pulse Pressure 120-80=40
– 𝐷𝑖𝑎𝑠𝑡𝑜𝑙𝑒 +
𝑃𝑢𝑙𝑠𝑒 𝑃𝑟𝑒𝑠𝑠𝑢𝑟𝑒
3
= 𝑀𝐴𝑃
– 80 +
40
3
= 80 + 13.3 = 93 𝑚𝑚𝐻𝑔