The major function of the cardiovascular system is transportation. Using blood as the transportvehicle, the system carries oxygen, nutrients, cellawastes, hormones, and many other substances vital.for body homeostasis to and from the cellsThe force to move the blood around the body isprovided by the beating heart and by bloodpressure.

+A hollow, cone-shaped organ,approximately the size of aperson's fist and weighs less than apound +It is enclosed within the medialsection of the thoracic cavity ormediastinum (inferior)

directed toward the left hip and rests on thediaphragm, approximately atthe level of the fifth intercostal faces

points toward theright shoulder and liesbeneath the second rib

a sac enclosingthe heart

protects and anchors the heart to the diaphragm and sternum

inner covering of the heart

protectsand anchors the heart to the Visceralpericardiuma diaphragm and sternum

what part of tge serous pericardium lines the interior aspect of the heart

parta of a serous pericardiym which is the part of the heart wall

Lubricating serous fluid is produced by theserous pericardial membranes and collectsin the pericardial cavity between theseserous layers

Inflammation of the pericardium that oftenresults in a decrease in the amount of serousfluid. This causes the pericardial layers toruh, bind and stick to each other, formingpainful adhesions that interfere with theheart movements.

+The heart walls are composed of three (3) layers

(visceral layer of Visceralpericardium serous pericardium)

consists of thick.Myocardium Bundles of cardiac muscle; Endocardium contracting layer

part of an heart wall that lines the heartchambers

+ The heart has four (4) hollow cavities or chambers:

j

receiving chambers

discharging chambers

divides theatria

divides the ventricles

divides atria and ventricles

great heart vessels

carryingof blood for gas exchange oxygenation of blood

main artery thatcarries blood away from yourheart to the rest of the body

transport of oxygenated bloodfrom left ventricle through thebody tissues and back to theright atriuma

flap or cusp that acts as one-way inlet for blood coming into a ventricle andone-way outlet for blood leaving a ventricle

The heart is equipped with four (4) valves:

"heart strings"; tinywhite cords that anchor the cusps to thewalls of the ventricles

tricuspid & mitral + prevent backflow into the atriawhen the ventricles contract

+Prevents arterial blood from reentering the heart Pulmonary & aortic

Condition when valve cusps become stiffaand does not close properly to backflowa

due to repeatedbacterial infection of the endocardium + Workload of heart increases = heartfailure

Functional blood supply of themyocardium is provided by the rightand left Coronary Arteries. Coronary arteries branch from thebase of the aorta and encircles theheart at the atrioventricular groove.

Marginal artery + Posterior Interventricular Artery

Anterior Interventricular Artery Circumflex Artery

return ondrain deoxygenated bloodfrom the myocardiumback to the right atrium.Most venous bloodreturns via the CoronarySinus.

Death of oxygen-deprived heartcells + Myocardium receives an inadequate blood supply when the heart beats at a very rapid rate

Crushing chestpain due to an oxygen-deprivedmyocardium; WARNING SIGN forMyocardial Infarction (MI) or heartattack

one day, the heartpumps approx.

built intohearttissue and sets its basic rhythm.

act like brakes and gapedalsto decrease or increase the heart, depending on which division isactivated

This system causes heart muscledepolarization in only one direction - from the atria to the ventricles.

pacemaker of the heart; starts Bundle branches each heartbeat

Atrioventricular (AV) node + Atrioventricular (AV) bundle(bundle of His) a +Bundle branches + Purkinje fibers

This transport of impulse results in a "wringing" contraction of theventricles that begins at the heart apexmoves toward theatria + This contraction effectively ejects blood superiorly into the largearteries leaving the heart

block" is a damage to the AV nodewhich blocks the SA node from controlling the ventricles;beating of heart becomes slower

medical device that is surgicallyinstalled in the body to generate electrical impulses toreplace and/or regulate the function of the SA Node or theconducting system.

lack of adequate. Blood supply to the heart muscle

rapid, uncoordinated quivering of theventricles; causes the heart to not be able to pump any blood and so is a major cause of death from heart attack in adults

rapid heart rate (over 100 beats per minute)

slower heart rate than normal (less than 60beats per minute)

Normal (N) Heart Rate:

+The events of one complete heartbeat, during which both atriaand ventricles contract and relax +Average Heart Rate: 75 beats per minute (60s) +Length of Cardiac Cycle: 0.8 seconds

heart contraction

heart relaxation

cycle is composed of events occurring five (5) periods:

Pressure in the heart is low + AV Valves are open, SL valves closed + Blood passively flowsthrough the atria into theventricles

increasingatrial pressure and completingventricular filling while theventricles are relaxed

+also known as "active ventricularfilling"

Atrial systole ends, andventricular systole begins AV valves closed - caused byincreased intraventricular pressure SL valves closed

Ventricles continue to contract,intraventricular pressure increased - SL valves open + Blood is ejected out from theventricles + Atria are again relaxed and filled withblood

Intraventricular pressure fails Ventricular diastole begins SL valves closed

When using stethoscope, you can hear two distinct sounds duringeach cardiac cycle. These heart sounds are often described by thtwo syllables "lub" and "dup/dub"

in what heart sound is closing of AV valves

in what heart sound SL valves close at the end of ventricular systole

Abnormal or unusual heart sounds when bloodflow becomes turbulent; usually.e to valve problems; common andnormal in young children with perfectly healthy hearts.

Blood circulates inside theblood vessels, which form aclosed transport systemcalled the

There are three (3) maintypes of blood vessels:

The walls of blood vessels have three (3)layers:

outermost layer composed largely offibrous connective tissue and functions to support and projectvessels

bulky middle layer made up of smooth muscle andelastic fibers; controlled bysympathetic nervous system (changing the diameter of thevessels)

lines the lumenthe interior of the vessels; form aslick surface that decrease friction asblood flows through

Walls of arteries are much_____than those veins, especially thetunica media. Arteries must be ableto expand as blood is forced intothem

Lumens of veins tend to be ____ than arteries and thicker tunicaexterna

Larger veins have ___ thatprevent backflow of blood likethose in the heart

- largest artery ofthe body

(R) Coronary Artery + (L) Coronary Artery+Supplies the heart

caused by plaque buildup in the wallsof the arteries that supply blood to theheart (called coronary arteries) andother parts of the body

is made up of deposits ofcholesterol and other substances in theartery. Plaque buildup causes theinside of the arteries to narrow overtime, which can partially or totallyblock the blood flow. This processcalled atherosclerosis.

Brachiocephalic Trunk + Common Carotid Artery

supplies the brain + External Carotid Artery - skinand muscles of head and neck

supplies thecerebellum, brainstem, spinal cord

Brachial Artery

Radial Artery

Ulnar Artery

an anatomical a structure that providesconnection betweenarteries of the brain.

Arteries for trunk muscles, lungs, esophagusand diaphragma

Arteries for internal organs (stomach, live intestines, kidneys, gonads) and abdomen andalower trunk muscles Arteries for bladder and rectum and for theentire leg.

Compared to arteries located indeep areas, veins are moresuperficial and some are easilyseen or palpated.

- upperbody (head & arms)

lowerbody

superficial drainageof the lateral aspect of the arm andempties into the axillary vein

superficial drainage ofthe medial aspect of the arm andempties into the brachial vein

cephalichand basilic join at the elbow (oftenchosen as the site for withdrawingblood for the purpose of blood

receivesvenous blood from the skin andmuscles of the head

large veinsthat receive venous drainage from thesubclavian, vertebral, and internaljugular veins to form the SVC

longest veins in the body;superficial drainage of theleg

formed by the union ofexternal and internal iliacvein to form the IVC