Cardiovascular Reviewer PDF

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Summary

CARDIOVASCULAR SYSTEM 4 Chambers: valve: COMPONENTS: atrium (LA) valve between RA and RV Heart Blood vessels Blood FUNCTIONS: 1. Regulates blood supply 2. Generates blood pressure 3. Routes blood 4. Ensures blood flow HEART CHARACTERISTICS: Size atrium (RA) ventricle (LV) ventricle (RV) Coronary sul...

Description

CARDIOVASCULAR SYSTEM

4 Chambers:

-Tricuspid valve:

COMPONENTS:

-left atrium (LA)

-AV valve between RA and RV

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Heart Blood vessels Blood

FUNCTIONS: 1. Regulates blood supply 2. Generates blood pressure 3. Routes blood 4. Ensures 1-way blood flow HEART CHARACTERISTICS: Size

-right atrium (RA) -left ventricle (LV) -right ventricle (RV)

Coronary sulcus -separates atria from ventricles

Orientation -apex (bottom) towards left side

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Upper portion Holding chambers Small, thin walled Contract minimally to push blood into ventricles Interatrial Septum: -separates right and left atria

VENTRICLES    

HEART LAYERS: Epicardium:

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-surface of heart (outside) Myocardium:

Lower portion Pumping chambers Thick, strong walled Contract forcefully to propel blood out of heart Interventricular septum: -separates right and left ventricles

-thick, middle layer composed of cardiac muscle

VALVES

Endocardium:

-structures that ensure 1 way blood flow

-Smooth, inner surface CHAMBERS AND BLOOD VESSELS

-2 cusps 

ATRIA

Location -between lungs in thoracic cavity

-Bicuspid valve (mitral): -AV valve between LA and LV

-size of a fist -weighs less than 1 lb.

-3 cusps

ATRIOVENTRICULAR VALVES (AV) -between atria and ventricles

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Chordae tendineae: -attached to AV valve flaps -support valves Semilunar valves: -Pulmonary: Base of pulmonary trunk -Aortic: Base of aorta

What happens when Bicuspid Valve is Open?   

Blood flows from LA into LV Aortic semilunar valve is closed Tension on chordae tendineae is low

What happens when Bicuspid Valve is Closed?   

Blood flows from LV into aorta Aortic semilunar valve is open Tension on chordae tendineae is high

Blood flow through Heart 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.

RA Tricuspid valve RV Pulmonary semilunar valve Pulmonary trunk Pulmonary arteries Lungs Pulmonary veins LA Bicuspid valve LV Aortic semilunar valve Aorta Body

Electrocardiogram -record of electrical events in heart -diagnoses cardiac abnormalities

-contains P wave, QRS complex, T wave Cardiac Cycle 

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-contraction of atria and ventricles by cardiac muscle cells 

Sinoatrial node (SA node): -in RA -where action potential originates -functions as pacemaker -large number of Ca 2+ channels

Path of Action Potential through Heart 1. SA node 2. AV node (atrioventricular) 3. AV bundle 4. Right and left Bundle branches 5. Purkinje fibers

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-uses electrodes

 Conduction System of Heart

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Heart is 2 side by side pumps: right and left Atria: Primers for pumps Ventricles: power pumps Cardiac cycle -repetitive pumping action which includes contraction and relaxation

Intrinsic Regulation of Heart -Mechanisms contained within heart 

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Heart Sounds 

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Stethoscope is used to hear lung and heart sounds First sound is lubb, second is dupp Sounds results from opening and closing valves Murmurs are due to faulty valves

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Regulation of Heart Function  

Stroke volume: -volume of blood pumped per ventricle per contraction -70ml/beat

Heart Rate: -number of heart beats in 1 min. -72 beats/min. Cardiac Output -volume of blood pumped by a ventricle in 1 min. -5 L/min. CO = SV x HR

Venous return: -amt. of blood that returns to heart Preload: -degree ventricular walls are stretched at the end of diastole Venous return, preload, stroke volume are related to each other Starlings Law of Heart -relationship between preload and stroke volume -influences cardiac output Ex. Exercise increases venous return, preload, stroke volume, and cardiac output After load: -pressure against which ventricles must pump blood

Heart Attack

Thrombus: -Blood clot blocks coronary blood vessels causes heart attack -daily aspirin can prevent by thinning blood 

Infarct -area that dies from lack of O2

Heart Procedures 

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Angioplasty -Procedure opens blocked blood vessels Stent: -Structures inserted to keep vessels open Bypass: -procedure reroutes blood away from blocked arteries...