PUMP IT UPNCSO Coaches Clinic

THE HEART

ANATOMY OF THE HEART

Base - Superior endApex - Inferior pointed end (left ventricle); rests on the diaphragm

• Pericardium – tough serous (connective tissue) membrane surrounding the heart

ANATOMY OF THE HEART

• Three layers:–Epicardium/ Visceral pericardium•Outer connective tissue layer (protection)

HEART WALL

–Myocardium:• Thick middle layer•Cardiac muscle: contracts to pump blood

–Thin inner layer composed of simple squamous epithelium - reduces friction for easier blood flow

ENDOCARDIUM

• Left & Right Atrium (Atria): Receiving chambers– Smaller with less muscle

• Left & Right Ventricles: discharging chambers– Left has thicker muscle layer than

right

HEART CHAMBERS

HEART VALVES

• Valves open as blood is pumped through• Close to prevent backflow• Two types are structurally different

• Right AV- Tricuspid Valve- three cusps of endocardium

• Left AV – Bicuspid/ Mitral valve – two cusps of endocardium

ATRIOVENTRICULAR (AV) VALVES

Right AV Valve Left AV Valve

• Hold the AV valves in place• Also called the “heart strings”

CORDAE TENDINAE

SEMILUNAR VALVES

• AORTIC - junction of left ventricle and aorta

• PULMONARY - junction of right ventricle and pulmonary arteries

• Produces the “lub-dup” sounds of a heartbeat

• “lub” = closing of AV Valves

• “dup” = closing of semilunar valves

THE CARDIAC CYCLE

• Pulmonary Circulation: between heart and lungs

• Systemic Circulation: between heart and capillary beds

BLOOD PATHWAY THROUGH THE HEART

• Deoxygenated blood from body enters right atrium via the superior/ inferior vena cava

• R. Atrium R. AV valve R. Ventricle pulmonary semilunar valve pulmonary trunk branches into left and right pulmonary arteries (4 total) to the lungs

BLOOD PATHWAY THROUGH THE HEART

While in the lungs CO2 diffuses out of the blood and oxygen diffuses into the blood and is transferred to RBC’s

• L&R Pulmonary veins (4 total) deliver oxygenated blood to the left atrium

• L. Atrium L. AV valve L. Ventricle aortic semilunar valve oxygenated blood to the body via the aorta

BLOOD PATHWAY THROUGH THE HEART

BLOOD COMPOSITION• Hematocrit –volume percentage (%) of

red blood cells • Plasma - 46-63%• Formed elements – 37-54%

PLASMA

• Non – living fluid matrix– 92% water– 7% plasma

proteins– 1% other solutes

• pH 7.35 to 7.45 – slightly alkaline

RED BLOOD CELLS (ERYTHROCYTES)

• About 1/3 of all body cells are RBC’s•Outnumber WBC’s 1000 to 1•One drop of contains ~ 260 million •Males have higher numbers than females – androgens promote RBC production

RBC STRUCTURE• Small size and “doughnut” shape

provide large surface area to volume ratio– Increases gas transport and

diffusion rate–Flexibility to squeeze through

capillaries• Lack organelles – cannot undergo cell division– Life span about 120 days

RBC FUNCTION

- Contain ~ 250 million hemoglobin molecules – iron bearing protein that transports the bulk of the oxygen

WHITE BLOOD CELLS (LEUKOCYTES)

–Account for less than 1% of total blood volume–Contain a nucleus–Defend against bacteria, viruses,

parasites and cancer cells

WBC CHARACTERISTICS

–Diapedesis - ability to slip in and out of blood vessels–Positive chemotaxis – ability to

locate areas of tissue damage and infection by responding to chemicals diffused from the damaged cells

WBC TYPES

Granular leukocytes

Agranular leukocytes

Most numerous

Least numerous

Found in lymphoid tissue

Numbers increase during prolonged infections

PLATELETS(THROMBOCYTES)

• Needed for blood clotting• Megakaryocytes - platelets break off from the larger cell• Typical platelet count ~ 300,000/mm3

RED BLOOD CELLS (ERYTHROCYTES)

• About 1/3 of all body cells are RBC’s•Outnumber WBC’s 1000 to 1•One drop of contains ~ 260 million

• Small size and “doughnut” shape provide large surface area to volume ratio– Increases gas transport and diffusion rate– Flexibility to squeeze through capillaries

RED BLOOD CELLS

• Lack organelles – cannot undergo cell division–Life span about 120 days

• Contain ~ 250 million hemoglobin molecules – iron bearing protein that transports the bulk of the oxygen

• Genetic disorder• Highest incidence in

people of African descent• Evolutionary adaptation

for surviving malaria –RBC’s have shorter life span, less flexible, can’t carry as much oxygen, “sickle shaped”

• People are generally tired and have painful attacks

• Limited activity

SICKLE CELL ANEMIA

WHITE BLOOD CELLS (LEUKOCYTES)

–Account for less than 1% of total blood volume–Contain a nucleus–Defend against bacteria, viruses,

parasites and cancer cells

WBC CHARACTERISTICS

–Diapedesis - ability to slip in and out of blood vessels–Positive chemotaxis – ability to

locate areas of tissue damage and infection by responding to chemicals diffused from the damaged cells

Most numerous

Least numerous

Found in lymphoid tissue

Numbers increase during prolonged infections

PLATELETS(THROMBOCYTES)• Needed for blood clotting• Megakaryocytes - platelets break off from the larger cell• Typical platelet count ~ 300,000/mm3

TYPES OF BLOOD VESSELS

Arteries: Vessels that carry blood away from the heart

*High pressureVeins: Vessels that return blood to the heart

*Valves to prevent backflow*Low pressure

TYPES OF BLOOD VESSELS• Arterioles – branch off arteries–Provide blood to more than 10

million capillaries• Venules – formed as capillaries join

together as they leave the tissues

TYPES OF BLOOD VESSELS

• Capillaries – ~ diameter of one RBC–Capillary beds supply tissues of the

body with gases & nutrients

• Build up of cholesterol as a plaque in artery/ arteriole walls

• May lead to heart attack or stroke/ high blood pressure

ATHERSCLEROSIS

• Lack of blood flow through coronary arteries causes death of heart tissue

MYOCARDIAL INFARCTION (HEART ATTACK)

RESPIRATORY FUNCTION

• Oxygenates blood for delivery to the cells

• Removes carbon dioxide (waste product) from blood

FUNCTIONAL ANATOMY OF

• The Nose – only externally visible part of the system

• Nostrils (external nares) – air enters the body

TRACHEA• Also called the windpipe• Lined with ciliated mucosa to propel

mucus loaded with dust and other foreign bodies away from the lungs and to the throat

• Rigid walls enforced with C – shaped rings of hyaline cartilage• Keeps trachea open during the

pressure changes that occur during breathing

• Relatively large organs which occupy the thoracic cavity

• Soft and spongy• Apex – located near

clavicle• Base – rests on the

diaphragm

LUNGS

• Only site of gas exchange in the lungs

• Structures include the alveoli, alveolar ducts, alveolar sacs and respiratory bronchioles

RESPIRATORY ZONE

MECHANICS OF BREATHING

RESPIRATORY MEMBRANE

• Also called the air-blood barrier

• Gas flows past one side and blood past the other

• Gas exchange occurs by diffusion through this membrane

• Oxygen passes from the alveolar air into the RBC’s and carbon dioxide enters the alveoli from the blood

COPD - (CHRONIC OBSTRUCTIVE PULMONARY DISEASE)

COPD – COMMON FEATURES

• History of smoking • Dyspnea – labored breathing that gets

progressively worse• Coughing/ frequent pulmonary infections• Ultimately develop respiratory failure

EMPHYSEMA

• Lung tissue weakened and destroyed

• Air spaces become larger• More difficult for air to

be exchanged in the lungs

• Lungs become less elastic

• Over time it becomes more difficult to release carbon dioxide and to obtain oxygen.

CHRONIC BRONCHITIS• Cough – 3 months to 2 yrs• Increased mucus in lumen• Chronic inflammation• Chronic thickening of the bronchial walls• Narrowed passageways

ASTHMA

• Chronically inflamed, hypersensitive bronchial passages

• Respond to multiple irritants with coughing, wheezing and dyspnea (labored breathing)

• Defective gene causes mucus secretions to become thick and sticky disrupting breathing & digestion

CYSTIC FIBROSIS

• Most preventable (over 70% of cases are caused by smoking)

• High mortality rate after diagnosis

LUNG CANCER