Review: Exam II

Cardiovascular Anatomy and Physiology

PED 205

Exam Format:Chapters: 12-13Multiple Choice: 30 Identification:

Intrinsic Conduction System, Blood flow through heart, Blood Vessel Cross Section

Short Answer: 5Select One Essay Question

Cardiac Anatomy:Pericardium: Visceral / ParietalEpicardium: Also visceral

pericardiumMyocardium: Cardiac muscle layerEndocardium: Connective Tissue

Heart Valves + Epithelium

Chambers and Valves:R. Atrium Tricuspid ValveR. Ventricle Pulmonary ValvePulmonary Artery LungsPulmonary Vein L. AtriumL. Atrium Mitral (Bicuspid) V.L. Ventricle Aortic ValveAorta

Coronary Arteries:Left Coronary Artery:

Origin: Left side of AORTASupplies: Anterior/Left Heart

Right Coronary Artery:Origin: Rt. Side of AORTASupplies: Right Heart

Coronary Artery Disease: CADNarrowed Coronary arteriesThrombus: Clot formsMyocardial InfarctionAngina PectorisCoronary Bypass CAB), angioplasty,

stents are treatments for CAD

Intrinsic Conduction System:SA Node: 90-100 bpmAV Node: Slows the message

downAV Bundles: (also His):L./R. Bundle Branches:Purkinje Fibers:

Cardiac Muscle Cells:Striated, Branched, Intercalated

DiscsSlower Action Potential than

nerve or skeletal muscle cellsVoltage Gated Ca++

Channels!

Electrocardiogram: ECG

P: Atrial Depolarization/contractionQRS: Ventricular Depol/ContractionT: Ventricular Repolarization

Cardiac Cycle:Ventricular Diastole:

Ventricles relax, fillPulmonary/Aortic Valves closeSecond Heart Sound: “Dupp”

Ventricular Systole:Ventricles Contract – eject bloodTri/Bicuspid valves closeFirst Heart Sound: “Lubb”

Cardiac Output: HR X SVCO = HR X SV“Emergencies”

SNS Autonomic NSIncrease HR/SV = Increase CO

“Relaxing”:PSNS Autonomic NSDecrease HR = Decrease CO

Baroreceptors: Pressure Emergencies Increase CO = Increase Systolic BPEmergency 1: Decreased Press

Increase SNS: Increased HR X SV = Increased CO

Problem 2: Increased PressDecrease SNS: Decrease HR =

Decreased CO

Chemoreceptors: Metabolism EmergenciesEmergency 1: Increased Metabolic Rate:

Increased CO2, H+ (decreased pH) Increased SNS …CO

Problem 2: Decreased Metabolic Rate: What’s the Problem?Decreased CO2/ H+ (increased pH)Decreased SNS …CO

Intrinsic Regulation of the Heart: Starling’s LawIncreased Venous Return

Increased cardiac muscle stretchIncrease contraction forceIncreased SV = Increased CO

Occurs without SNS/PSNS involvement

Exercise….

Blood Vessels And Circulation

Arteries and VeinsElastic, Muscular and

ArteriolesCapillaries:

Exchange/Diffusion/ OsmosisVenules, Veins

Three Tunics:Tunica Adventitia (Externa):

Fibrous connective tissueTunica Media: Smooth Muscle

and elastic connective tissueTunica Intima: Endothelium

(forms the valves in veins

Arterial Blood PressureCardiac Output: Systolic blood

pressureVascular Resistance: Diastolic

PressureVessel DiameterBlood ViscosityVessel Length

Pressure and Resistance

Increased Resistance = Increased Pressure

Increased Resistance = Increased Work of the Heart

Measurement: 120/80 mm Hg

Vasoconstriction:Decreases Vessel DiameterIncreases ResistanceIncreases Diastolic BP

Increases Work of HeartIncreases SBP later

SNS, Cold, Hemorrhage etc cause vasoconstriction to “rescue” vital organs

Vasodilation:Increases Vessel DiameterDecreases ResistanceDecreases Diastolic PressurePSNS, Heat, Local Exercise

Demand cause vasodilation to perfuse skin, muscles for special situations

Arteriosclerosis

Limits VasodilationIncreases ResistanceIncreases PressureRisk Factors:

Obesity, Cholesterol, Inactivity, Smoking, Aging, Heredity

Systolic and Diastolic BP:Systolic: Ventricular Systole

Greatest Arterial PressureReflects CO and heart’s contribution to BP

Diastolic: Ventricular DiastoleLowest Arterial PressureReflects the resistance of the vessels to

CO

Essay Choices:Exercise and the Heart/VesselsChronic Hypoxic Vasoconstriction

of the Pulmonary ArteriesThe effect of Nitroglycerin on

peripheral resistance, work of the heart, BP