Heart and Lung Function and Disease Flashcards
Pericardium
-fibrous sac around heart
-Serous layers: Parietal (outer), visceral (on heart and contains fluid within space)
-Innervated by Phrenic Nerve (sensory)
Diastole
-Relaxation
-Filling
Systole
-contraction
-ejection
Afterload
pressure needed to expel blood from the heart
-synonymous with BP
Myocardium
Cardiac muscle fiber
-actin-myosin complex
-Automaticity: contract w/o external stimuli
-Rhythmicity: contract with rhythm
-Conductivity: nerve impulses from one cell to the other due to intercalated discs
-Intercalated disc junctions: Desmosomes (adhesion) and Connexins (conductivity)
Endocardium
-Smooth muscle, innermost layer
Pulmonary Artery
-only artery to carry deoxygenated blood
Pulmonary vein
-only vein to cary oxygenated blood
Right Coronary Artery
-Supplies right ventricle, AV node and SA node
-Right posterior descending
-Right marginal
Left Coronary Artery
-supplies left ventricle, L atrium, septum, SA node
SA Node
-sets heart at pace of >100 without other input
-Susceptible to disease due to pericarditis, occulsion
Sympathetic NS
-increase
-norepinephrine
Inotropic
-strength of contraction
Chronotropic
-speed of contraction
Parasympathetic NS
-decrease
-vagus nerve
-acetylcholine
-60-90 bpm
AV Node
-receive from SA
-to Bundle of His to bundle branches to perkinjie fibers
-40-60 bpm without exernal stimuli
-0.04s to contract Vs
Susceptible to disease due to RCA occlusion
P Wave
atrial depolarization
PR interval
-travel of impulse to Vs
QRS Complex
ventricular depolarization
T Wave
ventricular repolarization
QT Internal
Ventricular systole
Low K
Harder to depolarize, slower heart rate
High K
Easier to depolarize as myocardium is excitable, higher heart rate
Cardiac Output
-CO= HR x SV
-5-6L at rest, can increased 4-7x with exercise
-Effects systolic BP
Blood Pressure
BP=HR x SV x Total peripheral Resistance
TPR affects diastolic BP
Mean Arterial Blood Pressure
-average pressure in the systemic system
MAP= DBP + 1/3 (SBP-DBP)
-Normal: 93 mmHg
-assess peripheral functions of CV
-cautions <60mmHg
Determined By:
-BV, CO, Peripheral resistance, distribution of blood in veins
Pulse Pressure
SBP-DBP, difference
Effect of Posture on BP
Standing: lower BP, blood pools in legs
Laying: blood evenly in veins, higher BP
BP Normal
<120/<80
BP Elevated
120-129/<80
High BP Stage 1
130-139/80-89
High BP Stage 2
> 140/>90
Hypertensive Crisis
> 180/>120