anatomy heart

Pulmonary Circuit

Right Atrium -> Right Ventricle -> Pulmonary Artery -> Lungs -> Pulmonary Veins -> Body Tissue -> Left Atrium

Cardiac Cycle

Ventricular Filling: Mid-to-Late Diastole -> Ventricular Systole

-> Isovolumetric Relaxation: Early Diastole

Pathway of Blood (13 Sites)

1. Superior & Inferior Vena Cava

2. Right Atrium

3. Right A.V. Valve/Tricuspid Valve

4. Right Ventricle

5. Pulmonary Semilunar Valves

6. Right & Left Pulmonary Arteries

7. Lungs

8. Right & Left Pulmonary Veins

9. Left Atrium

10. Left A.V. Valve?Bicuspid Valve

11. Left Ventricle

12. Aortic Semilunar Valve

13. Aorta/Aortic Arch

Intrinsic Conduction System (5)

1. SA Node (Pacemaker)

2. AV Node

3. AV Bundle

4. Bundle Branches

5. Purkinje Fibers

Tricuspid Valve AKA

Right A.V. Valve

Tricuspid Valve connects

Right Atrium to Right Ventricle

Aortic Semilunar Valve connects

Aorta to Left Ventricle

Pulmonary Semilunar Valve connects

Pulmonary Trunk to Right Ventricle

Biscuspid Valve AKA

Left A.V. Valve, Mitral Valve

Bicuspid Valve connects

Left Atrium to Left Ventricle

Atria

Receiving chambers of blood

Ventricles

Pumps blood out of heart

A.V. stands for

Atrioventricular

Semi-Lunar Valves prevent

Backflow into ventricles

Heart beat sounds are made by

1. Atria pumping blood to ventricles (A.V. Valves close)

2. Ventricles pumping blood (S.L. Valves close)

Superior Vena Cava

Connected to Aorta, Blue

Inferior Vena Cava

Bottom of the Heart, Blue

Chordae Tendinae

String-like tendons attached to each A.V. Valve flap, prevents backflow

Systemic Circuit

Left Atria -> Left Ventricle -> Body Tissue -> Vena Cava -> Right Atria

All-or-None Law states

The heart contracts completely or it fails to contract (asystole)

Cardiac Cycle duration

0.8 seconds per Cardiac Cycle

Pulmonary Arteries pump

De-oxygenated blood

Pulmonary Veins pump

Oxygenated blood back to the heart

Heart position

Under the 2nd rib, above the diaphragm

The heart gets rest during the…

Refractory Period

Cardiac Output

The amount of blood pumped out by each ventricle in 1 minute

Cardiac Output Equation

CO=HRxSV

C.O. stands for

Cardiac Output

H.R. stands for

Heart Rate

S.V. stands for

Stroke Volume

Ventricular Fibrillation

Chaotic, irregular ECG deflections, seen in acute heart attack and electrical shock

Longer Refractory Period prevents

Tectanic Contractions

Coronary System

Delivers blood when the heart is relaxed, ineffective when ventricles are pumping

Freshly oxygenated blood is received by the

Left Atrium

Sympathetic Simulation increases

Force of Contraction

Action Potentials are conducted from

cell to cell across myocardium via gap junctions

The Left Ventricular Wall is thicker than the Right because

It pumps blood against greater resistance

Sequence of contraction of the heart chambers

Both Atria followed by both Ventricles

An ECG provides information about

Movement of the excitation wave across the heart

Where is the AV Bundle located

Interventricular System

When SL Valves are open…

A.V. Valves are closed, ventricles are in systole, blood enters Pulmonary Arteries and Aorta

What tells our heart to beat?

Brain Stem