Cardiovascular System

Anatomy and Physiology

Circulatory System

• Maintains the distribution of blood flow through out the body• Includes: The Heart, blood vessels, Arteries, Capillaries, and

veins• Has two parts: The Pulmonary Circulation and The Systemic

Circulation• The Pulmonary Circulation: transports deoxygenated blood

between the heart and lungs• The Systemic Circulation: transports oxygenated blood away

from the heart to tissues and cells, and returns oxygen back to the heart

• Collects waste from the body and cells• Carbon dioxide is transported by the circulatory system from

lungs, liver, kidneys• Has Four Valves

The Heart

• Is made up of cardiac muscle• The heart has four chambers• Average beat is 60-100 bpm, 100,000 times daily• Each time the cardiac muscle contracts, blood

pushes through the body within blood vessels• The heart is locate in the mediastinum( center of the

chest cavity)• About the size of a fist, shaped like an up-side-down

pear• The lower edge of the heart is called the apex• The wall of the heart has three layers

Layers of the Heart

1. Endocardium: Inner layer of the heart• Lines the chambers of the heart• Reduces friction as the blood passes through the chambers2. Myocardium: The middle layer• Contractions help develops the pressure needed to pump

blood through blood vessels3. Epicardium: The outer layer • This layer is double-layer pleural-sac called pericarium• The visceral pericardium: Inner layer• The Perietal Pericardium: Outer layer• Fluid between the layers helps the sacs reduce friction as the

hearts beats

Pulse and Blood Pressure

• Blood Pressure is a measurement of the force exerted by blood against the wall of a blood vessels.

• A Ventricular Systole: the blood is under a lot of pressure from contracting

• Systolic Pressure is the highest blood pressure reading

• Diastolic Pressure is the lowest blood pressure reading

• Pulse is the surge blood caused by the heart contraction

Chambers of the heart

• Two atria( upper chambers) receiving chambers• Two ventricles( lower chambers) pumping chambers • Both have a thick myocardium and contracts, ejects blood out of the

heart into the arteries• Interatrial Septum( right side)• Interventricular Septum( left side)

Valves of the Heart

• Four valves • Restrains and controls

the direction of flow of the blood

• They allow the blood to flow forward in direction “only”, by blocking the previous chamber

Valves

• Pulmonary Valve

(semi lunar valve)• Located between the

right ventricle and the pulmonary artery

• Prevents the blood from returning to the right ventricles as it relaxes

• The Tricuspid (atrioventricular valve)

• Controls the opening between the right atrium and right ventricle

• Once the blood enters the right ventricle, it cannot go back

• Has three leaflets

Valves( continued)

• Mitral Valve

(bicuspid valve)• Has two cusps• Blood flows through the

atrioventricular valve and keeps it from returning through the left atrium

• Aortic Valve

(a semi lunar valve)• Located between the

left ventricle and aorta• Blood leave the left

ventricle and cannot return

Blood Vessels( three types)

• Arteries: large, thick-wall vessels Carries blood away from the heart Muscles can contract and relax to change size of the arterial lumen Coronary arteries provides blood to capillaries• Capillaries: thin-wall vessels Has network of tiny vessels called capillary beds Allows diffusion of the oxygen and nutrients from the blood into the body tissues Blood flow does not flow as quick as the arteries and veins• Veins: thin-wall vessels Carries blood back to the heart Can collapse easily Prevents blood from back-flowing Ensure the blood flows toward the heart

Blood Flow Through the Body

1. Deoxygenated blood pumps to the right atrium( the superior vena cava and Inferior vena cava

2. From the right atrium to the tricuspid valve3. To the right ventricle4. Blood pumps to the pulmonary valve 5. From the pulmonary valve to the pulmonary

artery( this carries oxygen to the lungs)6. To the left atrium( where it receives blood)7. Returns blood to the heart, to the relaxed

atrium( from the four pulmonary valves)8. Left atrium contracts blood, sends blood to the

mitral valve, and relaxed in the left ventricle9. From the left ventricle to the aortic valve, to the

aorta, and through out the rest of the body

Pathologies of the Heart

• Hypertension: Blood pressure above the normal range

• Hypotension: Decrease in blood pressure

• Thrombophlebitis: Inflammation of the vein, from blood clots in the vein

• Varicose Veins: swollen veins

Diagnostic Procedures

• Clinical Laboratory Tests: cardiac enzymes, serum lipoprotein level

• Diagnostic Imaging: angiography, cardiac scan, venography

• Cardiac Function Tests: Cardiac Catheterization, Electrocardiography, Holter Monitor, Stress testing

Therapeutic, Surgical Procedures

• Defibrillation• Cardiopulmonary

resuscitation• Extracorporeal

Circulation• Pacemaker Implantation• Aneurysmectomy• Arterial Anastomosis• Embolectomy• Heart Transplantatiion• Valve Replacement

Conclusion

The Circulatory System is essential for the human body. It helps transport nutrients and oxygen through out the body. The heart alerts us that we are alive by contracting( beats). This is why we must take care of ourselves. By not smoking, drinking plenty of water, and get plenty of exercise to keep the heart strong