Health Sciences & OccupationsHealth Sciences & Occupations

Anatomy, Physiology and Disease Anatomy, Physiology and Disease

Chapter 12Chapter 12The The CardiovascularCardiovascular System System

IntroductionIntroduction

Cardio-vascular systemCardio-vascular system TransportsTransports nutrientsnutrients & & oxygenoxygen to cells in body to cells in body

while while carbon dioxidecarbon dioxide and and waste productswaste products of cells’ of cells’ metabolism are removed.metabolism are removed.

PumpPump that circulates the transport medium ( that circulates the transport medium (bloodblood) ) is the heart.is the heart.

System OverviewSystem Overview

Components includeComponents include heart, heart, blood, and network of blood blood, and network of blood vessels.vessels.

ArteriesArteries carry blood carry blood aawayway from heart, branch into from heart, branch into smaller vessels called smaller vessels called arteriolesarterioles, which become , which become capilcapillarieslaries, where nutrients , where nutrients are exchanged; capillaries are exchanged; capillaries become become venulesvenules, that enlarge , that enlarge and become and become veinsveins..

System Overview con’tSystem Overview con’t

VeinsVeins differ from differ from arteriesarteries because they carry blood because they carry blood toward hearttoward heart, have valves, and have thinner walls., have valves, and have thinner walls.

The HeartThe Heart Size of your fistSize of your fist: located slightly left of center of : located slightly left of center of

chest.chest. Base isBase is proximalproximal to your head while to your head while apexapex is is distaldistal.. One single organOne single organ but with but with two pumpstwo pumps working working

together.together. Right sideRight side collects blood from body and sends it to collects blood from body and sends it to

lungslungs; ; left sideleft side collects blood from lungs and sends collects blood from lungs and sends it to it to rest of body.rest of body.

Four Chambers in HeartFour Chambers in Heart

SeptumSeptum: seperates heart in right & left half: seperates heart in right & left half Interatrial SeptumInteratrial Septum: seperates right Atrium from : seperates right Atrium from

left Atrium. left Atrium. Interventricular SeptumInterventricular Septum: seperates right & left : seperates right & left

ventricles.ventricles.

Chambers of the Heart con’tChambers of the Heart con’t

Right AtriumRight Atrium: collecting chamber where blood is : collecting chamber where blood is returnedreturned to heart after trip around body. to heart after trip around body.

SuperiorSuperior & & Inferior Vena CavaeInferior Vena Cavae: large veins return : large veins return blood to right atrium.blood to right atrium.

Tricuspid ValveTricuspid Valve ( (atrioventricularatrioventricular)): directs blood : directs blood from rt. Atrium from rt. Atrium toto rt. Ventricle. rt. Ventricle.

Chambers of the Heart con’tChambers of the Heart con’t

Heart contraction occursHeart contraction occurs: when rt. Ventricle is : when rt. Ventricle is full of full of bloodblood..

Tricuspid valveTricuspid valve prevents backflow of blood into prevents backflow of blood into rt. Atrium.rt. Atrium.

Blood flowsBlood flows through pulmonary semilunar valve through pulmonary semilunar valve to “to “pulmonary arteriespulmonary arteries.”.”

Chambers of the Heart con’tChambers of the Heart con’t

Rt. & Lt. Rt. & Lt. ““pulmonary arteriespulmonary arteries”” goes to lungs goes to lungs where vessels get smaller and smaller, ending in where vessels get smaller and smaller, ending in capillaries around each air sac (capillaries around each air sac (alveolusalveolus))

Blood returns to Lt. Atrium via “Blood returns to Lt. Atrium via “pulmonary pulmonary veinsveins.”.”

Chambers of the Heart con’tChambers of the Heart con’t

Mitral Valve (Bicuspid Valve)Mitral Valve (Bicuspid Valve): allows blood flow : allows blood flow from Lt. Atrium to Lt. Ventricle.from Lt. Atrium to Lt. Ventricle.

Left ventricular pressure increases as it fillsLeft ventricular pressure increases as it fills Heart contractsHeart contracts forcing forcing mitral valvemitral valve (Bicuspid (Bicuspid

Valve) closed.Valve) closed. Blood is ejectedBlood is ejected through aortic semilunar valve to through aortic semilunar valve to

ascending aorta, and then out ascending aorta, and then out toto rest of bodyrest of body..

The Route of an The Route of an RBCRBC

The Route of an The Route of an RBCRBC Superior/Inferior vena cavaSuperior/Inferior vena cava Right AtriumRight Atrium Tricuspid valveTricuspid valve Right VentricleRight Ventricle Pulmonary ValvePulmonary Valve Pulmonary ArteryPulmonary Artery LungsLungs Pulmonary Veins Pulmonary Veins Left AtriumLeft Atrium Bicuspid ValveBicuspid Valve Left Ventricle Left Ventricle Aortic ValveAortic Valve AortaAorta

Chambers of the Heart con’tChambers of the Heart con’t

SystoleSystole: : contraction phasecontraction phase when blood is when blood is ejected from the ventricles.ejected from the ventricles.

ContractionContraction: begins at : begins at apex apex and travels and travels upwardupward DiastoleDiastole: : resting periodresting period when chambers refill when chambers refill

with blood.with blood.

Chambers of the Heart con’tChambers of the Heart con’t

Atrial wallsAtrial walls: : thinnerthinner than ventricular walls than ventricular walls

Ventricular wallsVentricular walls:: Lt. ventricle pumps blood to body thus thick wallsLt. ventricle pumps blood to body thus thick walls Rt. Ventricle pumps blood to lungs thus thinner Rt. Ventricle pumps blood to lungs thus thinner

walls.walls.

Coronary ArteriesCoronary Arteries

Right coronary arteryRight coronary artery: : provides blood forprovides blood for right right ventricle, posterior portion of ventricle, posterior portion of interventricular septum, and interventricular septum, and inferior parts of heart.inferior parts of heart.

Left coronary arteryLeft coronary artery: : provides blood toprovides blood to left lateral left lateral and anterior walls of left and anterior walls of left ventricle, and portions of ventricle, and portions of right ventricle and right ventricle and interventricular septum.interventricular septum.

Pathology Problems (Pathology Problems (CHFCHF))

Rt. SideRt. Side Heart FailureHeart Failure:(cor pulmonale) :(cor pulmonale)

Etiology: Etiology: muscles chronically work muscles chronically work harderharder than than normal resulting in large muscle &normal resulting in large muscle & inefficient inefficient pumping; pulmonary embolus, COPD.pumping; pulmonary embolus, COPD.

S/S:S/S: SOB, wheezing, engorged liver & spleen, ankle, SOB, wheezing, engorged liver & spleen, ankle, feet & hand edema, & JVD (feet & hand edema, & JVD (distended neck veinsdistended neck veins))

Dx:Dx: Chest X-ray Chest X-ray

Rx:Rx: O2, diuretics, digitalis, nitrates, thrombolysis O2, diuretics, digitalis, nitrates, thrombolysis

Heart Failure (Heart Failure (CHFCHF))

Formally called Formally called Congestive Heart FailureCongestive Heart Failure ( (CHFCHF))

EtiologyEtiology: heart cannot move blood efficiently. Pump : heart cannot move blood efficiently. Pump cannot overcome resistance in blood vessels.cannot overcome resistance in blood vessels.

S/SS/S: enlarged liver, spleen, JVD, swelling of feet, : enlarged liver, spleen, JVD, swelling of feet, ankles, and/or hands. Dyspnea, SOB, chest pain, ankles, and/or hands. Dyspnea, SOB, chest pain, hypoxia.hypoxia.

DxDx: CXR, ABGs (arterial blood gases): CXR, ABGs (arterial blood gases)

RxRx: diuretics, digitalis: diuretics, digitalis

Rt & Lt Rt & Lt CHFCHF

Myocardial InfarctionMyocardial Infarction ( (MIMI))

EtiologyEtiology:: InfarctInfarct: tissue damage & death that results : tissue damage & death that results from completely blocked blood flow from blood clot from completely blocked blood flow from blood clot in coronary blood arteries (in coronary blood arteries (coronary thrombosiscoronary thrombosis))

Myocardial InfarctionMyocardial Infarction ((MIMI) Cont’d) Cont’d

S/SS/S: CP or heaviness, pain to Lt. shoulder, arm or : CP or heaviness, pain to Lt. shoulder, arm or jaw; N/V, weakness, SOB, clammy-sweaty jaw; N/V, weakness, SOB, clammy-sweaty feeling, dizziness, anxiety, “feeling, dizziness, anxiety, “indigestionindigestion.”.”

Odd S/SOdd S/S: little or no pain; called : little or no pain; called silent MIsilent MI, women , women exhibit “exhibit “non-traditionalnon-traditional” s/s like jaw pain. ” s/s like jaw pain.

DxDx: EKG, CXR, ABGs, CK-MB & Troponin blood : EKG, CXR, ABGs, CK-MB & Troponin blood tests. tests.

RxRx: ASA 162mg PO, O2, sublingual NTG , MS : ASA 162mg PO, O2, sublingual NTG , MS (morphine sulfate IV), anticoagulants Heparin or (morphine sulfate IV), anticoagulants Heparin or clotbusters clotbusters

MeasurementsMeasurements used to diagnose used to diagnose MIMI

CK-MBCK-MB: enzyme creatine kinase in heart muscle : enzyme creatine kinase in heart muscle cells, can be detected in blood within cells, can be detected in blood within 2-6 hours2-6 hours post MI.post MI.

TroponinTroponin: increases in blood approximately : increases in blood approximately 4-64-6 hours after MIhours after MI

Causes of MICauses of MI

ArteriosclerosisArteriosclerosis:: ThickeningThickening of inner layer (“hardening”) of arteries of inner layer (“hardening”) of arteries Vessels become less flexible or brittleVessels become less flexible or brittle, increasing , increasing

risk of rupture & likelihood of hypertension.risk of rupture & likelihood of hypertension.

AtherosclerosisAtherosclerosis:: Fatty depositsFatty deposits called plaques build up on inner called plaques build up on inner

lining of blood vesselslining of blood vessels.. Plaque of cholesterolPlaque of cholesterol; build up can block blood flow; build up can block blood flow Risk FactorsRisk Factors: heredity; diabetes; diet and lifestyle: heredity; diabetes; diet and lifestyle

AtherosclerosisAtherosclerosis

Rx for AtherosclerosisRx for Atherosclerosis

Coronary AngioplastyCoronary Angioplasty: : balloon-tipped catheterballoon-tipped catheter threaded up to large plaque; balloon is inflated, threaded up to large plaque; balloon is inflated, squishing plaquesquishing plaque to side & increasing blood flow. to side & increasing blood flow.

Rx for Atherosclerosis 2 of 3Rx for Atherosclerosis 2 of 3

Intracoronary stent placementIntracoronary stent placement: stents are : stents are wirewire devices that hold blood vessel devices that hold blood vessel openopen after after angioplasty; can preventangioplasty; can prevent re-occlusion re-occlusion of blood of blood vessel.vessel.

Rx for Atherosclerosis 3 of 3Rx for Atherosclerosis 3 of 3

Coronary artery bypass graftCoronary artery bypass graft ( (CABGCABG): surgical ): surgical procedure where procedure where healthy blood vesselshealthy blood vessels from from another part of body are used to another part of body are used to replacereplace clogged clogged coronary arteries.coronary arteries.

The Heart’s Electrical SystemThe Heart’s Electrical System

Cardiac muscle is Cardiac muscle is autorhythmicautorhythmic Specialized cardiac cells that create & distribute Specialized cardiac cells that create & distribute

electrical current that causes electrical current that causes myocardial contractionsmyocardial contractions..

Nodal Cells, or Nodal Cells, or Pacemaker Pacemaker CellsCells

Specialized cellsSpecialized cells that not only create electrical that not only create electrical impulse, but create impulses at regular interval.impulse, but create impulses at regular interval.

Divided into 2 groupsDivided into 2 groups, , SinoatrialSinoatrial ( (SASA) node & ) node & AtrioventricularAtrioventricular ( (AVAV) node. ) node.

Sinoatrial (Sinoatrial (SASA) node) node

Located in wall of right atriumLocated in wall of right atrium near entrance of near entrance of superior vena cava.superior vena cava.

Generates electrical impulseGenerates electrical impulse at approximately at approximately

70–8070–80 impulses per minute. impulses per minute.

Atrioventricular (Atrioventricular (AVAV) node) node LocatedLocated at point where atria & ventricles meet at point where atria & ventricles meet GeneratesGenerates electrical impulse at rate of electrical impulse at rate of 40–60 40–60 beats beats

per minute.per minute. Acts as a “Acts as a “back-upback-up” if SA node fails” if SA node fails

Factors that affect Heart RateFactors that affect Heart Rate

EmotionEmotion FeverFever Blood/water lossBlood/water loss Ions, hormonesIons, hormones Gender: Gender: MalesMales = 64-72, = 64-72, FemalesFemales = 72-80 = 72-80 HypokalemiaHypokalemia: Low K+ = weak heartbeat: Low K+ = weak heartbeat HypercalcimiaHypercalcimia: High calcium can prolong heart : High calcium can prolong heart

muscle contractions to point where heart can stop muscle contractions to point where heart can stop beating.beating.

PQRSTPQRST

P WaveP Wave::

AtrialAtrial Contraction Contraction QRS complexQRS complex::

VentricularVentricular contractions. contractions. T WaveT Wave::

VentricularVentricular repolarization repolarization

Pathology ConnectionPathology Connection

ArrhythmiaArrhythmia ( (dysrhythmiadysrhythmia): ): AbnormalAbnormal heartbeat heartbeat Due toDue to electrical problem, electrolyte or fluid electrical problem, electrolyte or fluid

imbalance or trauma, drug overdose.imbalance or trauma, drug overdose.

Electrical Pathway of the HeartElectrical Pathway of the Heart

Normal Sinus RhythmNormal Sinus Rhythm ( (NSRNSR))

P wavesP waves present, consistent & regular present, consistent & regular R wavesR waves regular regular RateRate = 60-99 bpm = 60-99 bpm

Sinus BradycardiaSinus Bradycardia

P wavesP waves present, consistent & regular present, consistent & regular R wavesR waves regular regular RateRate = 40-60 bpm = 40-60 bpm Can be Can be normalnormal if athletic if athletic

Sinus TachycardiaSinus Tachycardia

P wavesP waves present, consistent & regular present, consistent & regular R wavesR waves regular & fast regular & fast RateRate = 100-150 bpm = 100-150 bpm

EtiologyEtiology NormalNormal: athletic activity: athletic activity AbnormalAbnormal: Fever, hemorrhage, hypoxia, fear, drugs: Fever, hemorrhage, hypoxia, fear, drugs

Premature Atrial Contractions Premature Atrial Contractions ((PACsPACs)) P wavesP waves present, consistent & regular present, consistent & regular R wavesR waves irregular and premature irregular and premature RateRate = varies = varies

Etiology:Etiology: NormalNormal: usually, not life threatening: usually, not life threatening AbnormalAbnormal: stress, fear, dieting, hypoxia : stress, fear, dieting, hypoxia

RX:RX: Remove emotional Remove emotional

or physical cause.or physical cause.

Junctional Rhythm (JR) Junctional Rhythm (JR) P wavesP waves absent absent R wavesR waves regular regular RateRate = 40 + = 40 +

Etiology:Etiology: Sinoatrial (SA) node failure, MI, CHF, hypoxia, drugsSinoatrial (SA) node failure, MI, CHF, hypoxia, drugs

RX:RX: O2O2 Atropine sulfateAtropine sulfate ExternalPacerExternalPacer Internal PacerInternal Pacer

Atrial FlutterAtrial Flutter P wavesP waves multiple & frequent @ rate of 230-380 bpm multiple & frequent @ rate of 230-380 bpm R wavesR waves regular & fast regular & fast Ventricular rateVentricular rate = varies & usually fast = varies & usually fast

Etiology:Etiology: Sinoatrial (SA) node failure, Sinoatrial (SA) node failure, hypertension, ,

coronary artery disease, and , and cardiomyopathy))

RX:RX: DrugsDrugs CardioversionCardioversion AblationAblation

Atrial Fibrillation Atrial Fibrillation ((A-FibA-Fib)) P wavesP waves very rapid & uncoordinated very rapid & uncoordinated R wavesR waves irregular & fast or slow irregular & fast or slow Ventricular rateVentricular rate = varies usually 80-100 bpm = varies usually 80-100 bpm

Etiology:Etiology: Sinoatrial (SA) node failure, Sinoatrial (SA) node failure, hypertension, ,

coronary artery disease, and , and cardiomyopathy))

RX:RX: DrugsDrugs CardioversionCardioversion AblationAblation

Unifocal Premature Ventricular ContractionsUnifocal Premature Ventricular Contractions ((PVCsPVCs))

P wavesP waves absent absent R wavesR waves irregular & wider than normal irregular & wider than normal Ventricular rateVentricular rate = irregular = irregular

Etiology:Etiology: Ischemia, MI, drugs, myocarditis, smoking, caffeine Ischemia, MI, drugs, myocarditis, smoking, caffeine

RX:RX: Remove causeRemove cause Drugs Drugs Oxygen Oxygen

Multifocal PVCsMultifocal PVCs

P wavesP waves absent absent R wavesR waves both positive & negative deflections both positive & negative deflections Ventricular rateVentricular rate = irregular = irregular

Etiology:Etiology: Ischemia, MI, drugs, myocarditis, smoking, caffeine Ischemia, MI, drugs, myocarditis, smoking, caffeine

RX:RX: Remove causeRemove cause Drugs Drugs Oxygen Oxygen

Ventricular Tachycardia Ventricular Tachycardia ((VTVT)) P wavesP waves absent absent R wavesR waves irregular & wider than normal irregular & wider than normal Ventricular rateVentricular rate = irregular = irregular Life threatening emergencyLife threatening emergencyEtiology:Etiology: a a tachycardia that originates in one of the that originates in one of the ventricles of the of the

heart RX:RX: Remove causeRemove cause Oxygen Oxygen Drugs Drugs Electrical or Electrical or chemicalchemical cardioversioncardioversion CPR if LOC orCPR if LOC or no pulseno pulse! ! !! ! !

Ventrical Fibrillation Ventrical Fibrillation ((V-FibV-Fib))

P wavesP waves absent absent R wavesR waves absent absent Ventricular rateVentricular rate absent absent Life threatening emergencyLife threatening emergency No pulseNo pulse

Etiology:Etiology: No coordinated atrial or ventrical contractionsNo coordinated atrial or ventrical contractions RX:RX: DefibrillationDefibrillation CPRCPR Drugs Drugs Oxygen Oxygen

PEAPEA: : Pulse-less Electrical ActivityPulse-less Electrical Activity P wavesP waves present, regular or irregular present, regular or irregular R wavesR waves regular or irregular regular or irregular RateRate = varies fast or slow = varies fast or slow

Etiology:Etiology: there is electrical activity, but the there is electrical activity, but the

heart does not contract.heart does not contract. results in an insufficient results in an insufficient cardiac output to generate a pulse to generate a pulse

and supply blood to the organsand supply blood to the organs..

Rx: Rx:

CPR with IntubationCPR with Intubation

Epinephrine, Atropine, Vasopressin

External Pacer

AsystoleAsystole

Etiology:Etiology: No cardiac electrical activity at allNo cardiac electrical activity at all No cardiac perfusion at allNo cardiac perfusion at all

Rx:Rx: CPRCPR Intubation O2Intubation O2 Drugs: Epinephrine, Atropine, VasopressinDrugs: Epinephrine, Atropine, Vasopressin prayer prayer

11stst Degree AV Block Degree AV Block

11stst Degree AV Block Degree AV Block

P P waves: present, but prolonged PR interval : present, but prolonged PR interval >.20 seconds>.20 seconds

R wavesR waves: present and regular: present and regular There is a delay between atrial depolarization There is a delay between atrial depolarization

and ventricular depolarization.and ventricular depolarization. EtiologyEtiology: enhanced vagal tone (for example in : enhanced vagal tone (for example in

athletes),athletes),myocarditis, MI, electrolyte , MI, electrolyte disturbances and medicationsdisturbances and medications

RXRX: treat cause, not a life-threatening : treat cause, not a life-threatening dysrhythmia dysrhythmia

22ndnd Degree AV Block: Type 1 Degree AV Block: Type 1

22ndnd Degree AV Block: Type 1 Degree AV Block: Type 1

P wavesP waves: “march out”; PR interval : “march out”; PR interval gradually lengthen in successive cycles gradually lengthen in successive cycles and the last P wave fails to conduct to the and the last P wave fails to conduct to the ventriclesventricles

R wavesR waves: irregular because there is a : irregular because there is a dropped QRS complex dropped QRS complex

Also known as Also known as WenckebachWenckebach

22ndnd Degree AV Block: Type 1 Degree AV Block: Type 1

EtiologyEtiology: parasympathetic excess (inhibits : parasympathetic excess (inhibits AV node), MI, myocarditis, and drugsAV node), MI, myocarditis, and drugs

RXRX: IV Atropine or Isoproterenol if : IV Atropine or Isoproterenol if symptomatic, tx causesymptomatic, tx cause

22ndnd Degree AV Block Type 2 Degree AV Block Type 2

Known as Mobitz 2Known as Mobitz 2 P wavesP waves: intermittently nonconductive, no : intermittently nonconductive, no

PR interval prolongation, can progress to PR interval prolongation, can progress to complete heart block, can be 2:1 block, complete heart block, can be 2:1 block, 3:1 block, or more (ratio: P waves to QRS)3:1 block, or more (ratio: P waves to QRS)

R wavesR waves: less present than P waves, only : less present than P waves, only present when there is conduction through present when there is conduction through AV nodeAV node

22ndnd Degree AV Block:Type 2 Degree AV Block:Type 2

EtiologyEtiology: MI, cardiomyopathy : MI, cardiomyopathy

RXRX: trancutaneous pacing, possible : trancutaneous pacing, possible implantable pacemakerimplantable pacemaker

http://lifeinthefastlane.com/wp-content/uploads/2011/04/Mobitz_II.gif

33rdrd Degree Heart Block Degree Heart Block

33rdrd Degree AV Block Degree AV Block

Complete heart blockComplete heart block No electrical impulses reach ventricles, No electrical impulses reach ventricles,

ventricles will occasionally fire on their ventricles will occasionally fire on their ownown

P wavesP waves: present, but not in sync with : present, but not in sync with QRSQRS

R wavesR waves: present, but not in sync with P : present, but not in sync with P waves, “ventricular escape beats” waves, “ventricular escape beats”

33rdrd Degree Heart Block Degree Heart Block

EtiologyEtiology: MI, cardiomyopathy, drugs, valve : MI, cardiomyopathy, drugs, valve abnormalitiesabnormalities

RXRX: definite internal pacemaker: definite internal pacemaker

BloodBlood

Fluid form of connective tissueFluid form of connective tissue Usually Usually 44 toto 66 liters of blood or liters of blood or 9 to 139 to 13 units units 7 to 9%7 to 9% of your total body weight of your total body weight Men have more than womenMen have more than women

3 Functions3 Functions TransportationTransportation RegulationRegulation ProtectionProtection

Blood TypingBlood Typing

AntigensAntigens Substance thatSubstance that stimulates stimulates immune system to immune system to

produce produce antibodiesantibodies..

AgglutinationAgglutination When antigens When antigens stick together stick together in little clumpsin little clumps

Type AType A Very commonVery common; about ; about 41%41% of American population of American population Type Anti-B antibodies presentType Anti-B antibodies present to fight the blood to fight the blood

Type BType B Plasma containsPlasma contains anti-A antibodies anti-A antibodies If person with type B blood was givenIf person with type B blood was given type A blood, type A blood,

anti-A antibodies would anti-A antibodies would attackattack donated red blood donated red blood cells and destroy them.cells and destroy them.

Antibodies cause agglutinationAntibodies cause agglutination, resulting in serious , resulting in serious harm & even harm & even deathdeath..

agglutination

Type ABType AB Contain bothContain both A and B self antigens A and B self antigens Neither A or BNeither A or B antibodies in plasma antibodies in plasma Type AB blood are called Type AB blood are called universal recipientsuniversal recipients

because they can accept because they can accept any typeany type of blood type of blood type transfusiontransfusion

Type OType O RBCs contain noRBCs contain no A or B antigens, but its plasma A or B antigens, but its plasma

contains both A & B antibodies.contains both A & B antibodies. can be givencan be given to anyone to anyone universaluniversal donor donor