Heart*Anatomy of the Heart with 2D animation Note: by moving the mouse over the heart students will be able to hear the pronunciations. http://www.nucleuscatalog.com/cardiovascular-system/search?search_category=3556

In a particular hospitals Intensive Care Unit, patients always died in the same bed, on Sunday morning, at about 11:00 a.m., regardless of their medical condition. This puzzled the doctors and some even thought it had something to do with the supernatural. No one could solve the mystery as to why the deaths occurred around 11:00 a.m. on Sunday, so a Worldwide team of experts was assembled to investigate the cause of the incidents.

The next Sunday morning, a few minutes before 11:00 a.m., all of the doctors and nurses nervously waited outside the ward to see for themselves what the terrible phenomenon was all about. Some were holding wooden crosses, prayer books, and other holy objects to ward off the evil spirits.

Just when the clock struck 11:00, Pookie Johnson, the part-time Sunday sweeper, entered the ward and unplugged the life Support system so he could use the vacuum cleaner.*

CIRCULATORY SYSTEMFUNCTIONS:

Transport (nutrients, wastes, oxygen, CO2, hormones)Immunity (leukocytes, antibodies)Temperature regulation (when you are cold, blood vessels constrict; when hot, they dilate)Penile erection

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COMPONENTS OF CIRCULATORY SYSTEM

HeartBloodBlood vessels (arteries, capillaries, veins)Lymph vessels and nodes

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THE HEARTThe heart is the simplest organ in the body. It does only one thing: pumps blood. It beats 42 million times a year. Its about the size of your clenched fist. Some of you have big fists, some have smaller fists.Its location is deep to the sternum. Take your left fist and place it on the sternum, then angle the bottom of your wrist to the left. When you say the Pledge of Allegiance, your hand is not over your heart. Its not on the left, its in the center.*

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Location of the Heart in the ThoraxThe heart is located in the MEDIASTINUM, which is the central compartment of the thoracic cavity. *

Layers of tissues around the heart:

Parietal pericardiumVisceralpericardiumPERICARDIUM1) Parietal pericardium2) Pericardial cavity3) Visceral pericardium

HEART1) Epicardium (same as visceral pericardium)2) Myocardium3) Endocardium*

PERICARDIUMSurrounds the heart (like a heart in baggie).The function is to lubricate the heart, so as it beats, it wont rub against anything.The pericardium is divided into two layers with a space between them filled with fluid:PARIETAL PERICARDIUM PERICARDIAL CAVITY VISCERAL PERICARDIUM

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PARIETAL PERICARDIUMThis is actually the outermost layer of thoracic cavity. Two layers:SEROUS LAYER (simple squamous epithelium). Watery fluid.FIBROUS LAYER (moderately dense fibrous connective tissue)*

VISCERAL PERICARDIUM (aka EPICARDIUM) Outermost layer of heart. It also has two layers:SEROUS LAYERFIBROUS LAYER

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Layers of tissues around the heart:

Parietal pericardiumVisceralpericardiumPERICARDIUM1) Parietal pericardium2) Pericardial cavity3) Visceral pericardium

HEART1) Epicardium (same as visceral pericardium)2) Myocardium3) Endocardium*

Structure of the Heart Figure 18.3Parietal pericardium

Visceral pericardiumPericardial cavityMyocardium of heartEndocardium of heartInside chamber of heart*

MYOCARDIUMThe heart muscle itself (myocardium) is made of what tissue? Cardiac muscle.

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ENDOCARDIUMThe lining on the inside of the heart. Has two layers:ENDOTHELIUM (simple squamous epithelium that provides a smooth surface for the blood to pass by).If there are any irregularities in the smoothness of the endothelium (from inflammation or infection), a platelet could catch on it and start a blood clot.Loose connective tissue (deep to the endothelium)

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PERICARDITISInflamed outer layer of heart. Fluid accumulates in pericardial cavity, putting pressure on heart.Pericarditis can also be caused by damage to the blood vessels blood leaks into pericardial cavity pressure. Pericarditis can lead to pericardial friction rub, adhesions, and additional excess fluid in the pericardial cavity. It does NOT lead to a myocardial infarct (heart attack).*

PERICARDITISCARDIAC TAPENADE: In severe cases of pericarditis, for example if there is a stab wound to the heart wall that causes fluid to exude into the pericardial cavity so much that the excess fluid compresses the heart and diminishes the hearts ability to pump and it causes an irregular heart beat. An irregular heart beat is called arrhythmia. But dont get this confused with arrhythmia that is caused from a problem with the SA or AV node. The irregular heart beat from cardiac tapenade is caused from fluid entering the pericardial cavity and putting pressure on the heart. Treatment is to stick a needle in the pericardial cavity and drain the fluid. http://catalog.nucleusinc.com/generateexhibit.php?ID=68030&ExhibitKeywordsRaw=&TL=&A=2

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ENDOCARDITISMore serious: Bacteria enter bloodstream from a break in the skin (dental procedures, IV drug abuse, catheter) damage to lining and valves blood clots.Those who already have damaged heart valves need prophylactic antibiotics before any procedure, even teeth cleaning.Dont get endocarditis (bacterial infection) mixed up with pericarditis, which can lead to cardiac tapenade.*

THE HEART IS TWO PUMPS: LEFT AND RIGHT LEFT PUMP:From lungs to bodyRIGHT PUMP: From body to lungs*

The Pulmonary and Systemic CircuitsFigure 18.1*

Heart ChambersEach pump has two types of chambers: ATRIUM and VENTRICLELeft AtriumLeft VentricleRight AtriumRight Ventricle*

Blood FlowDeoxygenated blood from body enters the RA through the superior and inferior vena cava.It pours through the TRICUSPID (RIGHT AV) VALVE into the right ventricle.Right atrium contracts, pushes blood into the right ventricle ventricle expands, then contracts with force. To prevent the blood from going back up into the atrium, need a valve.*

Blood FlowBlood comes from the superior or inferior vena cava, into the right atrium, past the tricuspid valve, into the right ventricle. It then goes past the pulmonary semilunar valve, and into the pulmonary arteries.IVCPulmonary arteriesSVCRARVTricuspid valvePulmonary Semilunar valve*

VALVESValves are like a swinging door that can only open one direction. But you can push against this door, since its only tissue. But if you tie a rope to the doorknob, it wont be able to go the wrong way. The ropes are called CHORDAE TENDONAE, (heart strings) which are anchored to pieces of myocardium called PAPILLARY MUSCLES.The contraction of the papillary muscles pulls on the chordae tendonae to close the valves, preventing a PROLAPSED VALVE (turned inside out).*

Figure 18.9aValves*

Function of the Atrioventricular ValvesFigure 18.9b*

Heart Valves Valve StructureFigure 18.8a*

Trabeculae carneae (spongy meat)Trabeculae carnae are masses of irregular spongy tissues which project from the inner surface of the right and left ventricles.The purpose of the trabeculae carneae is to prevent suction that would occur when the ventricles contract and their inside surfaces touch each other. If the surface was flat, it would stick and impair the heart's ability to pump efficiently.The trabeculae carneae also serve a similar function to papillary muscles in that their contraction pulls on the chordae tendineae, preventing prolapsed mitral (bicuspid) and tricuspid valves.

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Trabecula Carnae*

What is an artery?An artery is a vessel that carries blood AWAY from the heart. It does not matter if it is oxygenated or deoxygenated blood.A vein is a vessel that carries blood TOWARD the heart. It does not matter if it is oxygenated or deoxygenated blood.*

Blood FlowWith the ventricular contraction, blood can go only one way: into the PULMONARY ARTERY (one of the few arteries with deoxy blood). When the ventricles relax, the PULMONARY SEMILUNAR VALVE closes to prevent blood from going from the pulmonary artery back into the right ventricle.

IVCPulmonary arteriesPulmonary veinsSVCRARVTricuspid valvePulmonary semilunar valve*

Function of the Semilunar ValvesFigure 18.10a, b*

Blood FlowWhen the ventricles relax, the PULMONARY SEMILUNAR VALVE closes to prevent blood from going from the pulmonary artery back into the right ventricle. Do the semilunar valves have a chordae tendonae? No; the blood is not being forced back (with a contraction), it just falls back with gravity, so theres not as much pressure.*

Blood FlowBlood then goes into lungs, gets oxygenated, and returns on the left side through the PULMONARY VEINS (one of the few veins with oxy blood), into the LEFT ATRIUM.LALVPulmonary arteriesPulmonary veinsTricuspid valveBicuspid (mitral) valve*Lungs

Blood FlowFrom the LEFT ATRIUM, it goes through the MITRAL VALVE (BICUSPID VALVE) into the LEFT VENTRICLE(there are also chordae tendonae here), which contracts. Therefore, the left ventricle is the chamber which is responsible for generating the largest pressure upon contraction.LALVPulmonary arteriesPulmonary veinsTricuspid valveBicuspid (mitral) valve*Lungs

Mitral ValveThe mitral valve gets its name from being the shape of a Bishops hat, called a mitre.

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Blood FlowThe blood then goes past the AORTIC SEMILUNAR VALVE, into the AORTA, and out to the body.*LALVIVCPulmonary arteriesAortaPulmonary veinsSVCRARVTricuspid valveBicuspid valvePulmonary semilunar valveThe semilunar valves are located between the ventricles and the great arteries.

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VALVES: Try before you BuyTRICUSPID VALVEBICUSPID VALVE (MITRAL VALVE) PULMONARY SEMILUNAR VALVE AORTIC SEMILUNAR VALVE

Structures associated with tricuspid and bicuspid valvesCHORDAE TENDONAEPAPILLARY MUSCLES

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Blood FlowDeoxy blood sup/inf vena cava R atrium tricuspid valve R ventricle pulmonary semilunar valve pulmonary artery lungs pulmonary veins Left atrium mitral (bicuspid) valve Left ventricle aortic semilunar valve aorta rest of body.*LALVIVCPulmonary arteriesAortaPulmonary veinsSVCRARVTricuspid valveBicuspid valvePulmonary semilunar valveAortic semilunar valve

Heart ChambersFigure 18.5e*

Heart ChambersFigure 18.5b*

Inferior View of the HeartFigure 18.5d*

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ApexRight atriumInterventricular septumLeft atriumRight ventricleLeft ventricleAtrial septum*

Mitral (bicuspid) valveCordae tendonaePapillary musclesAortic semilunar valveTrabeculae carnae*

Mitral Valve Stenosis If there is stenosis (blockage) of the mitral valve, where will the blood back up into?Answer: the pulmonary circulation. This is one disorder where the patient might cough up blood.LALVPulmonary arteriesPulmonary veinsTricuspid valveBicuspid (mitral) valve*Lungs

HEART BEATSThe pressure of blood against blood vessel walls is called blood pressure.Blood pressure is recorded systole over diastole. Normal resting blood pressure is said to be 120/80. When blood pressure is too high, it is called HYPERTENSION.The sound your heart makes when it is beating is the sound of the blood hitting the valves after they are closed.The heart normally beats at a rate of 60-80 beats per minute. A faster (tachycardia) or slower (bradycardia) heart rate is an indication of a problem.*

HEART BEATSAll four chambers cannot contract at the same time. Only two at a time can contract.The left and right ventricles contract at the same time = SYSTOLE.When the ventricles are relaxed = DIASTOLE.At which stage do the atria contract? Diastole.*

HEART BEATSSYSTOLE: Ventricles contract Atria relaxDIASTOLE:Ventricles relaxAtria contract*

HEART BEATSStart of Systole: Closing of valves (tricuspid and mitral) causes blood to hit the valves, making a sound. Systole of the ventricle means that this chamber is contracting.End of Systole: Closing of semilunar aortic and pulmonary valves causes blood to hit the valves, making a sound*

HEART BEATSLub-Dub is the sound of the blood hitting the closed valves. Start of Systole: Closing of the large valves (tricuspid and mitral) = LUB sound from blood hitting them. End of Systole: Closing of semilunar valves (aortic and pulmonary)= DUB sound (Dub) from blood hitting them.*

Heart SoundsFigure 18.11*

Valve ProblemsHEART MURMUR If the valve leaks, it doesnt close all the wayLub-squirtMost murmurs are benign; fairly common, esp. in babies and some adults.

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Abnormal Heart SoundsFriction rubsGallopsMurmurs

http://www.wilkes.med.ucla.edu/intro.html

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Valve ProblemsPROLAPSED VALVE is more serious. The valve turns all the way inside out.Mitral valve is most likely to prolapse because it pumped the hardest. See how much thicker the left ventricle is? Mitral Valve Prolapse is the most common heart valve disorder. Might need artificial valve.*

Artificial ValveThe Sapien Transcatheter Heart Valve (THV) is made of cow tissue and polyester supported with a stainless steel mesh frame. To replace the diseased valve, the Sapien THV is compressed into the end of a long, thin, tube-like device called a delivery catheter, which is slightly wider than a pencil, and inserted into the femoral artery through a small cut in the leg and threaded to the site of the diseased valve.*

Porcine (Pig) Valve *

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What controls the heart beat?There is a small region in the right atrium = SA NODE (Sino-atrium node) = pacemaker of the heart. Its job is to speed up or slow down the heart rate as needed. SA node sends an electrical signal (action potential) to the AV NODE (atrio-ventricular node) atrium contraction then the signal pauses before the signal is transmitted to both ventricles (atria are now relaxing) sends the action potential to all parts of the ventricles so they can contract.*

Conducting SystemFigure 18.12PLAYIntrinsic Conduction System*

Heart BeatsThe heart does not need a nerve to stimulate it to contract; rather, specialized heart cells can spontaneously start an action potential that spreads to depolarize the rest of the cardiac muscle cells. These are the specialized cells:A. SA nodeB. AV nodeC. Bundle of His (AV bundle)D. left and right bundle branchesE. Purkinje fibers

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Heart BeatsThis is the order in which these specialized cells function:

First the Sinoatrial (SA) node starts an action potential which causes the atria to depolarize. This depolarization will then reach the AV node at the bottom portion of the right atrium and there is a delay here because these cells are so small in diameter. Another delay in the transmission of the depolarization at the bundle of His (AV bundle) because these special heart cells travel through the atrioventricular septum which is non-conductive fibrous connective tissue. The Bundle of His slows down the electrical pathway to give the atria a chance to finish contacting.Next, the depolarizing event travels through the left and right bundle branches, found in the interventricular septum, to finally arrive at the Purkinje fibers in the lateral walls of the myocardium of the ventricles.

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Conducting SystemFigure 18.12PLAYIntrinsic Conduction System*

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Impulse PathwaySA nodeAV nodeBundle of His (conduction slows down here because this area is fibrous connective tissue, not muscle cells. This gives the atria time to contract before the ventriclesRight and left bundle branches on the IV septumPurkinje fibers on the lateral wall of the ventriclesnow they contracthttp://www.phschool.com/science/biology_place/biocoach/cardio1/electrical.html*

EKG*

ProblemsARRHYTHMIA Problem with the SA or AV node improper heart beat. Treatment is medicines or a pacemaker.*

FibrillationFIBRILLATION is when the heart beat is not really presentit just vibrates. A heart in fibrillation does not contract rhythmically; it just quivers without pumping blood.The ventricles are unable to pump blood efficiently due to rapid, random contraction of cardiac muscle fibers. The muscle doesnt contract as a unit.*

FIBRILLATIONTreatment is defibrillate with electric shock closes down heart maybe it will restart. This machine is never used when someones heart is beating with a lub-dub sound, even if it is irregular, because it causes the heart to stop. Whatever caused the fibrillation in the first place is not treated, so it may not work, but its worth a try! Most large public facilities have them. There are several on most college campuses. Disneyland has one every 100 yards.

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Fun FactIf someone with a pacemaker dies, does their heart keep beating?No. A pacemaker can only stimulate an irregularly beating heart, not a dead one. The pacemaker would almost certainly be triggered, since it would detect the absence of a regular heartbeat, but it would be to no avail. *

THE HEART NEEDS ITS OWN BLOOD/O2 The endocardium gets plenty of O2 from the blood cells that touch this layer as they travel through the heart, but the oxygen does not diffuse all the way into the myocardium, which is a deeper layer. *

THE HEART NEEDS ITS OWN BLOOD/O2 Therefore, the myocardium needs its own blood supply by CORONARY ARTERIES and VEINS. They are on the surface of the heart, and there are four of them. *

Coronary VesselsRight coronary arteryThe left one is too short to be counted2) Circumflex artery3) Anterior Interventricular artery4) Posterior Interventricular artery

The coronary sinus is a collection of veins joined together to form a large vessel that collects blood from the myocardium of the heart and delivers it into the right atrium.*

Heart Chambers*Figure 18.5b

Inferior View of the Heart*Figure 18.5d

THE HEART NEEDS ITS OWN BLOOD/O2 The more you do aerobic exercise, the more branches of these arteries are formed between themselves (anastomosis), and the better the blood supply to the heart. When blood vessels fuse together where they meet it is said that they ANASTOMOSE. This is a safety mechanism that allows blood to get through if one of the vessels gets clogged. People who exercise have the same number of heart attacks as those who dont, but they tend to survive them because they have more anastomoses.

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THE HEART NEEDS ITS OWN BLOOD/O2 If one of the four coronary arteries becomes clogged, ISCHEMIA (lack of oxygen) to part of the heart muscle will result. This is a painful condition, and the pain of it is called ANGINA (heart pain). If nothing is done immediately to increase the blood flow, the myocardial tissue can die; this condition is called a myocardial infarct (HEART ATTACK). VIDEOhttp://www.dnatube.com/video/1966/Myocardial-Infarction

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Diagnosis of MIAbnormally high cardiac enzymes in the blood is evidence of a heart attack.The most commonly tested cardiac enzyme is creatinine phosphokinase (CPK isoenzymes test).Creatinine phophokinase is present in heart, brain, and skeletal muscle, so having it elevated may only mean the person was physically active recently.However, these enzymes can be detected as separate types:CPK-BB (CPK-1) - concentration in the brain and lungs (caused by stroke, or lung injury)CPK-MM (CPK-3) - found mostly in the skeletal muscle. CPK-MB (CPK-2) - found mostly in the heart (also called Troponin-I )CPK-2 level increases after three to six hours following a heart attack, peak within 12- 24 hours (or longer depending on the severity of the heart attack) and return to normal level 12 - 48 hours after tissue death. Confirmation of heart attack when CK-MB is elevated and the ratio of CK-MB to total CK (relative index) greater than 2.5 - 3. 9 A hospital patient can be diagnosed with a normal electrocardiogram but have elevated creatinine phosphokinase (CPK-MB) elevation indicating a heart attack. *

Angina AttackPeople who have an angina attack can take nitroglycerine as a tablet under the tongue that dissolves quickly. This medicine will dilate the blood vessels. *

Weird ER StoryA 28-year old male was brought into the ER after an attempted suicide. The man had swallowed several nitroglycerine pills and a fifth of vodka. When asked about the bruises about his head and chest he said that they were from him ramming himself into the wall in an attempt to make the nitroglycerine explode.

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Coronary BypassWhen a person has their first angina attack, the doctor will order an ANGIOGRAM to look for a narrowing in an artery, especially in one of the coronary arteries. *

ANGIOGRAMAn ANGIOGRAM is a procedure to inject dye into the arteries and x-ray to see if there is narrowing (sclerosis) of a vessel. This can be done anywhere in the body that is of interest, but frequently it is done to check the coronary arteries. *

Angiogram*

ANGIOPLASTYIf an artery is too narrow, an ANGIOPLASTY can be performed to open it up. This involves sticking a balloon into the artery and inflating it, causing the vessel to enlarge a little to increase blood flow. This can be done anywhere in the body, but is frequently done in coronary arteries.*

Angioplasty*Stent Video 1Stent Video 2

http://www.the-scientist.com/?articles.view/articleNo/34766/title/Mimicking-Mussels/Scientists develop a gel that mimics mollusc glue to coat the insides of blood vessels.*

Coronary BypassIf a coronary artery is found to have a severe blockage, they can do a CORONARY BYPASS. In this procedure, the doctor takes another blood vessel graft (from the greater saphenous vein in the thigh) and sews it in around the blockage.For double or triple bypasses, thats how many vessels are affected. *

Blood Supply to the HeartFigure 18.14*

Superior vena cavaR. Coronary arteryAortaPulmonary trunkPulmonary veinsLeft subclavian arteryLeft common carotid arteryBrachiocephalic trunkR. subclavian arteryR. common carotid arteryL. Coronary arteryL. Pulmonary arteryAnterior interventricular artery Circumflex arteryAuricle (ear-shaped flap on the right atrium*

TERMSANGINA: heart pain, usually caused from not enough oxygen to the myocardium (ischemia)ISCHEMIA: lack of blood/oxygenMYOCARDIAL INFARCTION: heart attack (cardiac tissue death) from a clot in coronary artery, causing ischemia (lack of oxygen), which causes angina (heart pain).*

HEART ATTACKNot enough blood to the hearts myocardium layer MILD ISCHEMIA severe pain: ANGINA (angina pectoris)Treatment is nitroglycerine to open arteriesComplete blockage not enough O2 to that area = SEVERE ISCHEMIA that part of heart muscle dies = MYOCARDIAL INFARCTION. Heart muscle never regenerates. If a large area dies, person will die.*

HEART ATTACKWhat are symptoms of a heart attack? Chest pain, pain down left arm, shortness of breath, nausea, tight pressure in chest. A common symptom is death. 50% of first heart attacks are fatal within 2 hours. If a person receives good treatment in the first 2 hours, they are more likely to survive. About million people die each year from heart attacks.*

HEART ATTACKA drug that can stop heart attacks in progress by dissolving clots is t-PA (also used to dissolve clots that are causing a stroke)Angioplasty is a surgical procedure to clean out a clogged artery.A beta blocker is a drug that slows down the heart rate (used for tachycardia)Aspirin reduces blood clot formationNitroglycerine dilates the coronary arteries so more blood can get in.*

Fun FactIf a person takes an aspirin once a day to prevent clots or a heart attack, they should take it at NIGHT.Aspirin has a half life of 24 hours, so its effect is strongest in the morning.Most heart attacks occur in the morning!*

Bayer has new Quick Release crystals that dissolve faster in your mouth.*

Heart Medicinest-PA (dissolves blood clots)Beta-blockers (slows heart rate)Aspirin (prevents blood clots)Nitroglycerine (dilates coronary arteries)*

FUN FACTS ABOUT THE HEART--According to German researchers, the risk of heart attack is higher on Monday than any other day of the week; there is more stress on that day.--A Giraffes heart is 2 feet across.--Heart disease is a big killer, but what animal causes the most human deaths?Sharks kill 10 people per year.100 people die each year from being stepped on by cows. *

*--But a cow is not the worlds most deadly animal, which kills the most people.

What IS the worlds most deadly animal?

*--The whitetail deer causes the most deaths because of all the traffic accidents they cause.

Blue Whale Heart Size*

VideosHeart 5 minsCapillaries 3 mins*

CIRCULATORY DISEASE CONDITIONS The leading cause of untimely death in the Western countries of the world is cardiovascular disease.There are several hereditary factors that influence whether a person will get cardiovascular disease: 1. family history of heart attack2. gender (males are high risk)3. race/ethnicity (African Americans high risk)*

CIRCULATORY DISEASE CONDITIONSWhether or not you have a hereditary factor, there are some things you can do to prevent heart disease with diet and exercise. Included in this is knowing your cholesterol level, lowering your LDL intake, use olive and canola oil rather than butter/cream. Some studies also suggest that antioxidant vitamins (A, E, and C) may help, but remember that too much vitamin A and E cause a lot more harm to the liver than good to the circulation.*

Causes of High Blood PressureBoth arteriosclerosis and atherosclerosis cause high blood pressure. ARTERIOSCLEROSIS (hardening of the arteries): caused by a build-up of calcium deposits in the artery wall; artery cannot expand with blood surges. The blood vessel becomes hard like a rock; it cant expand or contract, causes increase in blood pressure. Tends to be hereditary.Diet and exercise dont help this much. *

Areteriosclerosis*

Causes of High Blood PressureATHEROSCLEROSIS (a build-up of fat in the arteries): caused from eating fatty food narrowing of artery Spasm shut or blood clot. *

Atherosclerosis*

EMBOLISMWhen fat builds up in a lump in one place, it is called a PLAQUE. It causes the lumen to narrow, restricting blood flow. If this fatty plaque breaks off and travels in the bloodstream, it is now called an EMBOLISM. An embolism can also be made of blood instead of fat.*

How a thrombus becomes embolismIf a platelet catches on a piece of this fat, it can start a blood clot (thrombus). If a piece of the clot (thrombus) breaks off and enters the circulation, it is now called an embolism, it can lodge in a smaller blood vessel and block the oxygen to all the tissue past that point, and the tissue dies.*

A thrombus can become an embolismA thrombus is made of BLOOD. It is a blood clot that is located on the inside wall of a blood vessel (usually a vein but not always) and it has not moved anywhere (yet).An embolism can be made of FAT or BLOOD. It is either a build up of fat in a vessel (usually an artery but not always) that has broken off a piece or a blood clot (usually in a vein but not always) that has broken off a piece. It travels and gets lodged in a smaller vessel somewhere.*

Blockage of blood vesselIf the embolism lodges in the coronary arteries myocardial infarct (Heart attack).If the embolism lodges in an artery in the brain strokeIf the embolism lodges in the lungs pulmonary embolism*

Pulmonary Embolism*

VENTRICULAR FIBRILLATIONEven a small clot can be a problem. If it happens to enter the interior of the heart and lodge in the wall of the atrium, it can block the conduction of the signal of the AV node VENTRICULAR FIBRILLATION.*

ANEURYSM High blood pressure is due to high pressure of blood against the walls of the blood vessels; the blood vessels compensate by developing a thicker wall. The vessels can no longer expand during systole, so the vessel gets thicker and thicker, and the blood pressure goes up more. If the blood pressure gets too high, an ANEURYSM can form, which is a weakening in the wall of the blood vessel, causing it to expand like a balloon. *

ANEURYSM Thus, an aneurysm is a sac-like outpouching of an artery. If it ruptures, its very dangerous. The aorta is the first artery that leaves the heart. It is under high pressure, so it is susceptible to getting aneurysims that can easily rupture; youll be dead in three heart beats. Can also get aneurysms in the brain that can rupture and causes stroke. Aneurysms often have no symptoms.*

Coronary artery disease termsCoronary artery diseaseAtherosclerosis fatty depositsAngina pectoris chest painMyocardial infarction blocked coronary arterySilent ischemia lack of blood flow that happens to not cause any pain or other symptoms until it hits a critical threshold; leads to an unexpected heart attack.Stroke ruptured blood vessel or blood clot in the brain. The proper medical term for a stroke is a Cerebral Vascular Accident (CVA)*

Clarification of TerminologyA blocked artery can occur anywhere in the body.A blocked CORONARY artery is what causes a heart attack. The coronary arteries are those that supply the myocardium of the heart. Ischemia is a lack of oxygen from lack of blood flow. It can occur anywhere in the body. When there is ischemia in your leg from sitting on it wrong, it is from lack of blood flow to the muscles of your leg. it gives you a pins and needles feeling but it will repair itself when you restore the blood flow. *

Clarification of TerminologyWhen there is ischemia in the heart, it is from a lack of blood flow to the myocardium of the heart (the actual muscle tissue of the heart). The only arteries that supply the heart are the coronary arteries. Therefore, ischemia in the heart can only be caused by some blockage in at least one coronary artery. In this case, a heart attack will ensue because ischemia in the heart causes permanent damage quickly. Fortunately. there are four coronary arteries, so many people can survive a heart attack if not all of them are blocked. That's why some heart attacks are called "mild heart attacks"; only a small piece of the myocardium died off and the heart is able to keep beating properly.*

Predictors of Heart AttackHigh Blood PressureHigh Cholesterol Large Waist Size*

Predictors of Heart AttackNormal blood pressure is 120/80. Pre-hypertension is 120 to 139 (systolic) and/or 80 to 89 (diastolic). Hypertension also known as high blood pressure -- is 140 or higher (systolic) and 90 or higher (diastolic). One in three adults in the U.S. has high blood pressure or pre-hypertension. *

Predictors of Heart Attack:Cholesterol levels you DONT wantTriglycerides of greater than 150 mg/dL.Total cholesterol higher than of 200 mg/dL. HDL ("good" cholesterol) lower than 50 mg/dL (females) or 40 mg/dL (males). LDL (bad cholesterol) higher than 100Unless you have other major risk factors, like diabetes, you want your LDL closer to 70. The new standards are to look at the ratio of Total Cholesterol to HDL; it should be less than 5. Example: 200/50 = 4 (healthy).Estrogen in women contributes to higher HDL levels, which decrease after menopause.Is your boss watching your cholesterol?http://fxn.ws/RwNGS1

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Left = NormalRight three = 44 years old, total cholesterol of 464, triglycerides are 3500*

Predictors of Heart AttackFEMALES: waist size more than 35 inches MALES: waist size more than 40 inchesMeasure around your belly button.If patients lose even 1 inch off their waist, there are improvements in all the other heart health numbersIf they gain even 1 inch, there is a worsening in those numbers. It's a much better indicator of heart health than weight.*

Other Heart ConditionsCongestive Heart failureProgressive weakening of the heartBlood backs up into lungs (may cough up blood)Cannot meet the bodys demands for oxygenated bloodHypertrophic cardiomyopathyCongenital condition where the walls of the left ventricle are so thick that the lumen is too small to hold much blood. *

Disorders of ConductionVentricular fibrillation Rapid, random firing of electrical impulses in the ventricles of the AV nodeAtrial fibrillation Rapid, random firing of electrical impulses of the SA node*

Most Common Heart Problems AtherosclerosisVentricular fibrillationCongestive heart failure Hypertrophic cardiomyopathy*

FUN FACTCan you die from laughing?It's certainly possible to die while laughing -- probably by choking on something. But laughing is actually very good for you. According to the Indiana University School of Medicine, laughing helps relax tense muscles, lowers blood pressure, and even burns calories. People with heart disease are 40% less likely to laugh in a given situation than people without heart disease. The key here seems to be stress reduction; stress impairs the production of endothelial cells, which form a protective lining in our blood vessels. A weak endothelium can lead to hardened arteries and, quite literally, a hardened heart.*

EMBRYONIC DEVELOPMENT OF THE HEARTThe heart is the most common site for congenital defects (those one is born with).During fetal life, the mother provides the oxygen and nutrients through the placenta. If there is a problem with the babys heart, it is not a problem until birth, although it can be detected by ultrasound.*

EMBRYONIC DEVELOPMENT OF THE HEART The earliest heart chambers

Figure 18.16a, b*

The Heart Throughout LifeFigure 18.16ce*

EMBRYONIC DEVELOPMENT OF THE HEARTAt 28 days (two weeks after a woman misses her period), the human heart first starts to beat and pump blood in the embryo (at the end of the fourth week).You have to stop smoking and drinking before you get pregnant. By the time you know youre pregnant, its too late for the babys heart.*

Fetal HeartWhere is the fetus getting the oxygen during the nine months in the womb? The mother, not the lungs of the fetus. So theres no sense in sending half of the fetuss bodys blood to the lungs for oxygen. *

Fetal Blood VesselsWhen oxygenated blood from theplacentais carried to thefetusby theumbilical vein, where does it go? About half of this blood enters theinferior vena cava of the fetus, while the other half enters theliver of the fetus. The blood in the inferior vena cava empties into the right atriumof theheart, and then moves directly into the left atrium instead of going to the lungs. Blood moves from the right atrium to the left atrium by going through a hole called the foramen ovale.Thus, blood bypasses the pulmonary circulation (does not go to the lungs of the fetus). *

missinglink.ucsf.edu*

FORAMEN OVALEThere is a foramen ovale in the skull and another one in the heart, between the two atria. The foramen ovale in the heart normally closes shortly after birth, and is then called the FOSSA OVALIS.A blue baby has low oxygen levels in the blood that may be due to failure of the foramen ovale to close at birth.When the foramen ovale fails to close, it is called a patent foramen ovale.Patent (Pay-tent) means open*

Foramen Ovale kardiol.com*

Fetal CirculationNot all of the blood in the right atrium goes through the foramen ovale to bypass the pulmonary circulation, because the lung tissue needs some oxygen. Therefore, some of thebloodentering the right atrium does not pass directly to theleft atriumthrough theforamen ovale, but enters theright ventricle(same as an adult) and is pumped into the pulmonary artery and goes to the lungs.*

Fetal CirculationHowever, the lung tissue of the fetus do not need that much blood, so there is a special connection between thepulmonary arteryand theaorta in the fetus, which directs most of this blood away from the lungs and back to the aorta.This connecting blood vessel is called theductus arteriosus.*

AdultFetuskvitters.comDuctus arteriosus*

Changes at BirthAt birth, there is an immediate change. Half of the blood needs to go to the lungs.At the first breath, a flap closes over the foramen ovale, and a muscle around the ductus arteriosus constricts, causing instant closing, and seals shut permanently.The foramen ovale is now called the fossa ovalis, and the ductus arteriosus is now called the ligamentum arteriosum.*

Ductus Arteriosus (fetus only)*

Ligamentum arteriosum (after birth)*

Patent Foramen OvaleWhen a baby has not started walking, it doesnt need as much oxygen, so a patent foramen ovale might not be noticed until they start to walk and run at age 2-3.However, every time the baby cries, it might turn blue.A patent foramen ovale can be surgically closed by going through the blood vessels without cutting into the heart tissue. A patent foramen ovale in an adult is just a tiny opening and can be heard as a heart murmur.You can also have a patent ductus arteriosus, which also requires surgery. *

Heart DeformitiesMore significant problems: interventricular septal defect (between right and left ventricle). Requires open heart surgery.*

Congenital Heart DefectsFigure 18.17a, b*

Artificial HeartIf heart is totally deformed, need transplant.

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Fetal CirculationIn the fetus, there is a branch off the internal iliac artery, called the umbilical artery.When blood from the aorta reaches the internal iliac artery, some blood goes into theumbilical arteries and re-enters theplacenta, wherecarbon dioxideand other waste products from the fetus are taken up by the maternal circulation.*

chw.org*

The Heart in Adulthood and Old AgeAge-related changesHardening and thickening of valve cuspsDecline in cardiac reserveSympathetic control over heart is less efficientLess severe in the physically activeFibrosis of cardiac muscle tissue Lowers the amount of blood the heart can pump*

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