Cardiovascular SystemCardiovascular System

•Organs and Cells Organs and Cells

•Organization and FunctionsOrganization and Functions

•Cardiovascular Health as a Cardiovascular Health as a Multifactorial Trait Multifactorial Trait

Heart Chambers and Valves

LeftLeftVentricleVentricle

RightRightAtriumAtrium

Right VentricleRight Ventricle SemilunarSemilunarValvesValves

Left AtriumLeft Atrium

AtrioventricularAtrioventricularValveValve

AtrioventricularAtrioventricularValveValve

Tissues of the HeartTissues of the HeartEndocardium- liningEndocardium- lining

Myocardium- muscleMyocardium- muscle

Pericardium- outsidePericardium- outside

Layers of Heart TissueLayers of Heart Tissue

FibrousFibrouspericardiumpericardium

Visceral Visceral pericardiumpericardium

The Cardiac CycleThe Cardiac Cycle

Atria ContractAtria Contract

DeoxygenatedDeoxygenatedblood from bodyblood from body

OxygenatedOxygenatedblood from lungsblood from lungs

Ventricles ContractVentricles Contract

DeoxygenatedDeoxygenatedblood to lungsblood to lungs

OxygenatedOxygenatedblood to bodyblood to body

Heart Relaxes;Heart Relaxes;atria fill passivelyatria fill passively

Flow of Blood to Lungs and BodyFlow of Blood to Lungs and Body

VentriclesVentricles

LungLungCapillariesCapillaries

Body CapillariesBody Capillaries

AtriaAtria

Control of Heartbeat

Sinoatrial (SA) Sinoatrial (SA) NodeNode

Atrioventricular Atrioventricular (AV) Node(AV) Node

ExcitableExcitableFibersFibers

SA Node = pacemaker

AV Node receives signals from SA node, sends signal through excitable fibers for ventricles to beat simultaneously

Connecting Vessels AortaAorta

Descending AortaDescending Aorta(to lower body)(to lower body)

Inferior Vena CavaInferior Vena Cava(from lower body)(from lower body)

SuperiorSuperiorVena CavaVena Cava(from upper body)(from upper body)

Pulmonary ArteryPulmonary Artery(to right lung)(to right lung)

Pulmonary Artery Pulmonary Artery (to left lung)(to left lung)

Pulmonary VeinsPulmonary Veins(from right lung)(from right lung)

Pulmonary VeinsPulmonary Veins(from left lung)(from left lung)

Blood Vessels of the HeartBlood Vessels of the Heart

Coronary arteries (red) Coronary arteries (red) and cardiac veins (blue) and cardiac veins (blue) serve heart muscleserve heart muscle

Imaging methods can Imaging methods can detect blockages in detect blockages in coronary arteries coronary arteries

Applying Your KnowledgeApplying Your Knowledge

A.A. Which structure receives blood returning Which structure receives blood returning from the lungs? from the lungs?

B.B. Which structure prevents blood from flowing Which structure prevents blood from flowing back into the ventricles?back into the ventricles?

C.C. Which structure pumps blood to the body Which structure pumps blood to the body capillaries?capillaries?

1.1. Left VentricleLeft Ventricle2.2. Semilunar ValveSemilunar Valve3.3. Right AtriumRight Atrium4.4. Left AtriumLeft Atrium5.5. Atrioventricular valveAtrioventricular valve

Heart Heart FunctionFunction

Heartbeat Heartbeat visualized visualized with ECGwith ECG

Atria Contract

VentriclesRelax

Atria RelaxVentriclesContract

AtrioventricularValves Close“lubb” sound

SemilunarValves Close“dup” sound

Irregular heart rhythmIrregular heart rhythm

ArteryArtery

VeinVein

ArterioleArteriole

CapillariesCapillaries

VenuleVenule

EndotheliumEndothelium

ConnectiveTissueConnectiveTissue

MuscleMuscle

ConnectiveConnective Tissue Tissue

Structures and Interconnections of Blood Vessels

--Arteries carry blood away from the heart--Veins carry blood back to the heart--Capillaries allow blood to reach tissues

Blood Return Through Veins Blood Return Through Veins

• Skeletal muscles Skeletal muscles help return blood help return blood to the heartto the heart

• Valves prevent Valves prevent back-flowback-flow

Blood PressureBlood Pressure

Blood pressure =Blood pressure =

Systolic pressureSystolic pressure

Diastolic pressureDiastolic pressure

Systolic: pressure during Systolic: pressure during ventricular contractionventricular contraction

Diastolic: pressure during Diastolic: pressure during ventricular relaxationventricular relaxation

Blood ComponentsBlood Components

Red blood cellsRed blood cellscarry oxygencarry oxygen

White blood cellsWhite blood cellsdefend against invadersdefend against invaders

Platelets initiatePlatelets initiateblood clottingblood clotting

Plasma is the fluid portion of Plasma is the fluid portion of blood that transports nutrients, blood that transports nutrients, gases, hormones and waste.gases, hormones and waste.

Lipid Carriers distributeLipid Carriers distributetriglycerides and cholesterol.triglycerides and cholesterol.

LDL = low density lipoproteinLDL = low density lipoprotein delivers cholesterol delivers cholesterol

HDL= high density lipoproteinHDL= high density lipoprotein returns cholesterol to returns cholesterol to liver for destruction liver for destruction

Applying Your KnowledgeApplying Your Knowledge

A.A. Which one transports nutrients? Which one transports nutrients?

B.B. Which one fights foreign invaders?Which one fights foreign invaders?

C.C. Which one carries oxygen?Which one carries oxygen?

1.1. PlasmaPlasma

2.2. Red blood cellsRed blood cells

3.3. White blood cellsWhite blood cells

Multifactorial and Multifactorial and Polygenic TraitsPolygenic Traits

• Multifactorial Trait: Phenotype is influenced by Multifactorial Trait: Phenotype is influenced by the environmentthe environment– Heritability: measure of genetic contribution to the Heritability: measure of genetic contribution to the

phenotypephenotype

• Polygenic Trait: Phenotype is determined by the Polygenic Trait: Phenotype is determined by the activities of more than one geneactivities of more than one gene– Show a range of phenotypesShow a range of phenotypes– Likely to also be Multifactorial TraitsLikely to also be Multifactorial Traits

Multifactorial Polygenic Trait: Multifactorial Polygenic Trait: Heart HealthHeart Health

Heart health depends on Heart health depends on

1.1. Blood pressureBlood pressure

2.2. Lipid metabolismLipid metabolism

3.3. Blood clottingBlood clotting

4.4. Tendency for white Tendency for white blood cells to adhere blood cells to adhere to blood vessel wallsto blood vessel walls

Genes Involved in Cardiovascular Health

Rare allelesrelated to risk for cardiovascular diseases