Chapter 13 Cardiovascular System

Basics of this systemOrgans

Heart Pumps 7k L/day

Blood Vessels ArteriesAtriolesCapilariesVenulesVeins

Two circuitsPulmonarySystemic

Without circulation, what would happen?

Structure of HeartBasics- Heart is a muscular pump.Location

Between 2nd and 5th intercostal spacePericardium

Visceral, ParietalWall of Heart

Epi-,Myo-,Endo- Cardium

Chambers and Valves

Flow of BloodStarting at Right atrium…

Tricuspid valveRight VentriclePulmonary ValvePulmonary ArteryLungsPulmonary VeinsLeft atriumBicuspid valveLeft VentricleAortic valveAorta

The cusps (flaps) of the bicuspid and tricuspid valves are anchored to the ventricle walls by fibrous “cords” called chordae tendineae, which attach to the wall by papillary muscles. This prevents the valves from being pushed up into the atria during ventricular systole.

1. Right Atrium 2. Right Atrioventricular Valve

(Tricuspid Valve) 3. Right Ventricle 4. Left Atrium 5. Left Atrioventricular Valve

(Mitral Valve) 6. Left Ventricle 7. Papillary Muscle 8. Chordae Tendinae

9. Mitral Valve cusps

Cardiac ConductionSA NodeJunctional FibersAV NodeAV BundlePerkinje Fibers

Bruce Protocol

Heart Actions

Heart Actions

Can you identify these parts?

Heart Actions

Heart ActionsDuring one complete heartbeat

Systole- contraction of chamberDiastole- relaxation of a chamber

Cardiac cycleDifference in pressures

Atria Ventricle 70% of blood moved by pressure alone

VentriclesArteries Difference in pressure

Atria fill as ventricles contract

Heart SoundsTwo part sound (use stethoscopes if

available)Lubb-Dupp

Lubb- ventricle contraction Dupp- ventricle relaxation

ECGElectrocardiogram

Recording of the electrical events during a cardiac cycle

P WaveDepolarization of the atria

QRS ComplexDepolarization of ventricles

T WaveRepolarization of the ventricles

Interpreting ECGsAn ECG is printed on paper covered with a grid of squares.Notice that five small squares on the paper form a larger square. The width of a single small square on ECG paper represents 0.04 seconds.  A common length of an ECG printout is 6 seconds; this is known as a "six second strip."

Analyze an ECG

Each one of the figures represents an ECG pattern displaying three types of abnormal rhythms: Tachycardia, Bradycardia, and Arrhymthmia. Identify each.

Regulation of Cardiac CycleVolume of blood pumped changes

ExerciseControlled by Medulla Oblangata

Parasympathetic Impulses decrease heart rate

Sympathetic Increase heart rate and force of contractions

TemperatureBaroreceptors

Cardiac OutputCardiac Output

Stroke VolumeLVEDV-LVESV

Heart Rate

Q=SV x HR

Changes in HR, SV, CO SNS

PNS

Venous Return

Exercise

Elite Athletes

Calcium

HR

BP

Arteries and Veins

Tunica Externa Tunica MediaTunica Interna

VasoconstrictionVasodilation

Capillaries

Blood PressurePressure is highest in arteries, why?

SystolicDyastolic

PulseRecoiling of the arterial walls

Factors Influencing BPStroke Volume

Blood discharged per contraction of ventriclesCardiac Output

SV x HRBlood volume

5 liters in adultPeripheral Resistance

Friction between blood and blood vesselsViscosity

Fluid content

Cardioinhibitor ReflexCardioaccelerator Reflex