Download Heart Notes

CARDIOVASCULAR
SYSTEM
Chapter 15
OVERVIEW

BASIC FUNCTION: Bulk Transport
– Move nutrients and gases to tissue areas
 Nutrients for energy, building materials
 Oxygen for cellular respiration
– Remove wastes from tissue areas
 Urea and other metabolic wastes
 Carbon dioxide

BASIC STRUCTURE: Heart + Vessels
– Heart – force pump
– Pulmonary Circuit – blood to lungs and back to heart
 Pulmonary Artery  alveoli + pulmonary capillaries 
pulmonary veins
– Systemic Circuit – circulation to all parts of body
 Arteries – take blood away from heart
 Capillaries – material exchange
 Veins – take blood towards heart
DIAGRAM
HEART STRUCTURE

Coverings

– Pericardium
 Outer layer
 Serous membrane
– Mycardium – cardiac
muscle tissue
 Thickest
– Endocardium – lines
chambers
 Purkinje fibers
DIAGRAM
Chambers
– Atria – upper (L & R)
 Double layered
 Separated by pericardial
cavity
– Epicardium – visceral
pericardium
INTERACTIVE DIAGRAM
 Auricles – outside flaps
– Ventricles – lower (L & R)
– Ineratrial and interventricle
septums

Valves  one way flow
– Chordae Tendinae and
Papillary muscles
– Tricuspid – b/w R. Atria &
R. Ventricle
– Bicuspid (mitral) – b/w L.
Atria & L. Ventricle
– Pulmonary Semilunar – b/w
R. Ventricle & Pulmonary
Arteries
– Aortic Semilunar – b/w L.
Ventricle & Aorta
VALVE
DIAGRAM
HEART STRUCTURE

Order of Blood Flow
(Deoxygenated Blood)
– Veins from Systemic (Body)
Circuit
– Superior/ Inferior Vena
Cava
– Right Atria
– Tricuspid Valve
– Right Ventricle
– Pulmonary Semilunar Valve
– Pulmonary Arteries
– Lungs (capillaries)
HEART DIAGRAM

Order of Blood Flow
(Oxygenated Blood)
–
–
–
–
–
–
–
–

Lungs (capillaries)
Pulmonary Arteries
Left Atria
Bicuspid Valve
Left Ventricle
Aortic Semilunar Valve
Aorta
Arteries of Systemic Circuit
Heart circulation
– Coronary arteries 
capillaries  cardiac veins
 coronary sinus
CARDIAC CONDUCTION SYSTEM

Specialized tissue to
transmit muscle
impulse for proper
heart contractions
– Functional synctium
– Self-excitatory

Cardiac cycle – 1
complete heartbeat

– Blood through A-V valves
– SA (sinoatrial) node
 Pacemaker
 Transmit impulse to atria

“lub” – “dup”
– 1st sound – A-V
valves
– 2nd sound –
semilunar valves
Atria diastole; Ventricle systole
– AV (atrialventricular) node  AV
bundle (Bundle of His)  purkinje
fibers
– Blood forced through semilunar valves
– “Lub” – AV valves slam shut
– Systole – contraction
– Diastole – relaxation

Atria systole; Ventricle diastole
 Murmur - defect

Atria diastole; Ventricle diastole
– Heart resets
DIAGRAM
EKG AND HEART ACTIONS

Electrocardiogram – graph of
electrical activity of heart during
cardiac cycle
– P wave – depolarization of atria
 Impulse causes atria systole
– P-Q interval – flat line
 Impulse travels from atria to ventricular
fibers
 No contraction
– QRS Complex – depolarization of
ventricles; repolarization of atria
 Ventricular systole
 Atria returning to relaxed state
– T wave – repolarization of ventricles
DIAGRAM
FACTORS AFFECTING
CARDIAC CYCLE

Parasympathetic pathways – inhibit
– Ach
– Vegas Nerve

Sympathetic pathway – excitatory
– Norepinephrine

Controlled by cardiac center (medulla oblongata)
– Baroreceptors in carotid arteries and aorta
– Cerebrum and hypothalamus
 Fainting – slow down
 Anxiety – speed up
– Temperature
– Ions

Arrythmias – irregular heartrate (ECG)
– Clinical Application 15.3 – P. 588 - 589
– Tachycardia, bradycardia, ventricular fibrillation
– ECG interactive tool
LAYERS OF THE HEART
OPERATION OF VALVES
ECG – Depolarization and
Repolarization of cardiac tissue
CORONARY ARTERIES &
CARDIAC VEINS