Circulatory System PDF

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THE CARDIOVASCULAR SYSTEM-transport of oxygen and nutrients needed by the cells -closed system of the heart and blood vesselsFunction: deliver oxygenand nutrients remove carbon dioxideand other waste products BLOOD VESSELS-allow blood to circulate to all parts of the bodyTwo Main Parts:1 CIRCULATORY...

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circulatory.system.midterms.reviewer.2019_aremti202x

THE CARDIOVASCULAR SYSTEM -transport of oxygen and nutrients needed by the cells -closed system of the heart and blood vessels Function: - deliver oxygen and nutrients -remove carbon dioxide and other waste products BLOOD VESSELS -allow blood to circulate to all parts of the body

A. VISCERAL PERICARDIUM -Next to heart B. PARIETAL PERICARDIUM -Outside layer PERICARDIAL CAVITY -space bet. Parietal and visceral serous pericardium SEROUS FLUID(100ml) -fills the space between the layers of pericardium called pericardial cavity PERICARDIAL SAC -gives ample space for heart during relaxation

Two Main Parts: 1.BLOOD CIRCULATORY SYSTEM -heart and blood vessels

PERICARDITIS -inflammation of the pericardium -decreased amounts of serous fluid

2.LYMPHATIC SYSTEM -lymphatic organs and lymph vessels

CARDIAC TAMPONADE -increased amounts of serous fluids

Circulations:

THE WALL OF THE HEART

CIRCULATORY SYSTEM -invloved in hemeostasis -ensures continues supply of blood to all body cells -rapid response to changes TWO SYSTEMS COMMUNICATE WITH EACH OTHER THROUGH:

EPICARDIUM -Outside layer - visceral pericardium -Connective tissue layer -thick

PULMONARY CIRCULATION -absorbs oxygen; gives CO2

MYOCARDIUM -Middle layer -Mostly cardiac muscle -thin

SYSTEMIC CIRCULATION -supplies oxygen; removes waste products -aorta to different parts of the body

ENDOCARDIUM -Inner layer -Endothelium (smooth surface) CHAMBERS OF THE HEART

THE HEART -pumps blood -acts as a pump Location: thorax (chest cavity) behind sternum specifically the middle mediastinum Weight: Male: 280-340 grams Female: 230-280 grams Shape: Conical shape with base (broader) Apex (pointed) directed toward left hip *the diaphragm is located at the 5th intercostal space THE HEART: COVERINGS PERICARDIUM -a double serous membrane -membranous covering of the heart

L&R ATRIUMS: receiving chambers L&R VENTRICLES: pumping/ chambers

discharging

Circluations: LA & LV: systemic to pulmonary RA& RV: pulmonary to systemic *Blood in the heart chambers does not nourish the myocardium VALVES -Allow blood to flow in only one direction -open as blood is pumped through -closed to prevent backflow -Held in place by chordae tendineae (“heart strings”)

circulatory.system.midterms.reviewer.2019_aremti202x

Four valves: ATRIOVENTRICULAR VALVES -between atria and ventricles L: Bicuspid valve R: Tricuspid valve SEMILUNAR VALVES -between ventricle and artery RV to Pul. Trunk: Pulmonary semilunar valve Bet LV & Aorta: Aortic semilunar valve BLOOD FLOW IN THE HEART

SUPERIOR/ INFERIOR VENA CAVA ↓ RIGHT ATRIUM ↓ TRICUSPID VALVE ↓ RIGHT VENTRICLE ↓ PULMONARY SEMILUNAR VALVE ↓ PULMONARY TRUNK ↓ PULMONARY ARTERY ↓ LUNGS ↓ PULMONARY VEINS ↓ LEFT ATRIUM ↓ LEFT VENTRICLE ↓ AORTIC VALVE ↓ AORTA

CORONARY CIRCULATION -nourishing circulatory system L&R CORONARY ARTERIES -branches that supplies the heart -branches of ascending aorta CORONARY SINUS - where blood lood empties into the right atrium -Main venous drainage of the heart CONDUCTING SYSTEM OF THE HEART INTRINSIC CONDUCTION SYSTEM/ NODAL SYSTEM -Heart muscle cells contract, without nerve impulses, in a regular, continuous way -automatically stimulated to contract w/o the need for a nerve supply from brain SINOATRIAL NODE (SA NODE/ PACEMAKER) -specialized cells -initiates impulses more rapidly than other groups of neuromascular cells ATRIOVENTRICULAR/ AV NODE -stimulated by impulses that sweep over the atrial myocardium -can stimulate impulses but slower than SA Node ATRIOVENTRICULAR BUNDLE -mass of specialzied fibers -Purkinje fibers NERVE SUPPLY TO THE HEART AUTONOMIC NERVES VAGUS NERVES SYMPATHETIC NERVES

MEDULLA OBLONGATA PARASYMPATHETIC SYMPATHETIC (increases heart rate)

circulatory.system.midterms.reviewer.2019_aremti202x

HEART CONTRACTIONS

CARDIAC OUTPUT = HEART RAT RATE E x STROKE VOL VOLUME UME

CONTRACTION -initiated by the SA node

HR is 80 beats/ minute = cardiac output is 5600 ml/min.

SEQUENTIAL SIMULATION -occurs at other auto-rhythmic cells

*Can be increased through to meet demands of exercise to much as 35 l/min in athletes (CARDIAC RESERVE)

CARDIAC CYCLE -events of one complete heart beat -where the heart contracts then relaxes

Starling’s law of the heart -the more that the cardiac muscle is stretched, the stronger the contraction

(”SIZ” *stressed) SYSTOLE= contraction (”DIE” *rest in peace) DIASTOLE = relaxation

Changing heart rate -most common way to change cardiac output FACTORS AFFECTING HEART RATE

60 to 80: Normal no. Of cardiac cycles per minute Each cycle consists of:   

ATRIAL SYSTOLE VENTRICULAR SYSTOLE COMPLETE CARDIAC DIASTOLE

Mid-to-late diastole -blood flows into ventricles Ventricular systole -blood pressure builds before ventricle contracts, pushing out blood

 Autonomic NS  Circulating chemicals -catecholamines, thyroxine, increased heart rate  Activity and Exercise -increase  Emotional States -excitement’ fear and anxiety  Gender -faster rater in women  Age -faster in babies and children  Temperature -increased in warm temp.

Early diastole -atria finish re-filling, ventricular pressure is low HEART SOUNDS

REGULATION OF HEART RATE INCREASED HEART RATE:

“lub dub” Lub -closure of tricuspid and bicuspid valves Dub -closure of aortic & pulmonary valves

 Sympathetic nervous system -Crisis, Low blood pressure  Hormones -Epinephrine, Thyroxine  Exercise  Decreased blood volume DECREASED HEART RATE:

ELECTROCARDIOGRAPH -machine used ELECTROCARDIOGRAM (ECG) -tracing

  

Parasympathetic nervous system High blood pressure or blood volume Decreased venous return BLOOD PRESSURE

CARDIAC OUTPUT - amount of blood ejected from heart -duration: 1 minute STROKE VOLUME - volume/ liters/ minute of blood pumped by each ventricle in one contraction Healthy adult at rest: Approx. 70ml

-force or pressure -blood exerts on the walls of the blood vessels SYSTOLIC BLOOD PRESSURE -LV contracts and pushes blood to aorta DIASTOLIC BLOOD PRESSURE -pressure within arteries when heart is resting

circulatory.system.midterms.reviewer.2019_aremti202x

Human normal range is variable Normal 120 mm Hg systolic 80 mm Hg diastolic Hypotension Low systolic (below 110 mm HG) Often associated with illness

 RADIAL ARTERY -wrist  FEMORAL ARTERY -upper inguinal sulcus  POPLITEAL ARERY -back of knee joint  DORSALIS PEDIS ARTERY -dorsum of foot BLOOD VESSELS

Hypertension High systolic (above 140 mm HG) Can be dangerous if it is chronic

-system of channels or passageway of circulating medium: blood

SYSTOLIC --------------DIASTOLIC

Three layers: 1. TUNICA INTIMA -Endothelium

Blood pressure effects of factors:

2. TUNICA MEDIA -Smooth muscle Controlled by sympathetic nervous system

TEMPERATURE -Heat has a vasodilating effect Cold has a vasoconstricting effect

3. TUNICA EXTERNA -Mostly fibrous connective tissue

CHEMICALS -Various substances can cause increases or decreases

ARTERY -carry blood away from heart -from aorta, it becomes smaller and smaller

DIET

VEIN -carry blood toward heart -from thinnest venules, they become bigger until the Vena Cava

Instruments used in getting bp: -SPHYGMOMANOMETER -STETHOSCOPE

ARTERIOLES -samllest arteries; less than 0.5 mm

PULSE -wave of distension and elongation -delt in an artery wall -contraction of LV -Monitored at “pressure points” where pulse is easily palpated Average no. of pulse beats per minute: Average 60-80/ minute (heart rate)

VENULE -smallest veins CAPILLARIES -diffuse network of thin tubules that connects one another -interchange of blood and tissues -connects arteries to the smalles veins DIFFERENCE OF ARTERY AND VEIN

factors that increases the pulse rate:     

POSITION AGE GENDER EXERCIS EEMOTION ARTERIES COMMONLY ASSESSED FOR PULSE

 CAROTID ARTERY -neck; sternocleidomastoid  BRACHIAL ARTERY -cubital fossa (anterior of elbow joint)

ARTERY Thick wall Away from heart Circular lumen pulsating Blood spurts

VEIN Thin wall Towards heart Oval/ collapsed lumen Not pulsating Blood oozes

CIRCULATION CIRCULATORY SYSTEM -invloved in hemeostasis -ensures continues supply of blood to all body cells -rapid response to changes

circulatory.system.midterms.reviewer.2019_aremti202x

PULMONARY CIRCULATION -absorbs oxygen; gives CO2 -heart to the pulmonary trunk

Thrombosis and Embolism -blood cloth

SYSTEMIC CIRCULATION -supplies oxygen; removes waste products -aorta to different parts of the body

 VARICOSE VEINS -dilated vein -valves do not close to prevent backflow of blood -vein that lost elasticity -elongated and tortuous

PORTAL CIRCULATION -capillaries of spleen and abdominal portion of gastrointestinal tract to the capillaries of the liver then to IVC to the heart -portal vein

Sites: 1. Legs 2. Hemorrhoids 3. Esophagus 4. Scrotum

FETAL CIRCULATION -temporary circulation seen during fetal life -has single umbilical vein and two umbilical arteries COMMON CLINICAL CONDITIONS

 SHOCK -inadequate flow of blood; hypoxia; accumulation of waste products Types: Hypovolemic -blood volume is reduced by 15-25% Cardiogenic -occurs in acute heart disease Septic -severe infection -endotoxins are released

HEART DISEASES  ANGINA PECTORIS -angina of effort -increased cardiac output -ischemic pain in chest arms, neck and jaw  MYOCARDIAL INFARCTION -infarct (dead area of tissue due to lack of oxygenated blood) -severe crushing chest pain behind sternum -continues even at rest  CARDIAC ARRHYTHMIAS -disorder of heart rate Normal sinus rhythm: 60-100 Sinus bradycardia: below 60 bpm Sinus tachycardia: above 100bpm

Anaphylactic -severe allergic reaction

 ASYSTOLE -no electrical activity in ventricles -no cardiac output -cardiac arrest

 ATHEROMA -narrows the lumen; MI

 FIBRILLATION -contraction of cardiac muscle fibers

 THROMBUS -intravascular clot

Atrial fibrillation -contraction of atria

 EMBOLUS mass of any material

Ventricular fibrillation -disruption of ventricular function

 ARTERIOSCLEROSIS – degenerative condition  ANEURYSM -dilatations of arteries Hemmorrhage -ruptured aneurysm; sudden death or disability Pressure -swelling

DISORDERS OF BLOOD PRESSURE  HYPERTENSION -BP that is sustained higher than normal level 20 years = 140/90 mmHg 50 years = 160/95 mmHg 75 years = 170/105 mmHg  HYPOTENSION -low blood pressure than normal -inadequate blood supply to brain -postural hypotension syncope (fainting)

circulatory.system.midterms.reviewer.2019_aremti202x

Developmental Aspects of the Cardiovascular System

 A simple “tube heart” -develops in the embryo and pumps by the fourth week  The heart becomes a four-chambered organ -by the end of seven weeks  Few structural changes occur -after the seventh week

REFERENCES:



Powerpoint Presentation of Dr. Valera



Lecture Guide and Laboratory Manual in Anatomy and Physiology 2nd Edition

NORMAN V. VALERA M.D. Department of Human Structural Biology FEU-Dr. Nicanor Reyes Medical Foundation Regalado cor. Dahlia Sts., West Fairview, Q.C., Phil....