Cardiovascular System

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Cardiovascular System
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The Cardiovascular System

• A closed system of the heart and blood vessels
• The heart pumps the blood.
• Blood vessels allow blood to circulate to all
  parts of the body.
• The function of the cardiovascular system is to
  deliver oxygen and nutrients and to remove carbon
  dioxide and other waste products.
• Your heart has special pacemaker cells that
  control the pumping action of the heart with an
  electrical signal.

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Pace maker cells
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The Heart

• Location
• In the chest between the lungs.
• Orientation
• The pointed tip is directed toward left hip.
• About the size of your two fiststogether.

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The Heart

• The heart is surrounded by a layer of tissue that
  protects it from damage and bacteria.
• The walls of the heart are 3 layers thick
• Epicardium (Outer Layer)
• Myocardium (Middle Layer) cardiac muscular
  layer
• Endocardium (Inner Layer)

Myocardium
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Four Chambers of the Heart

• Left and right refers to persons right and left
  sides, not yours.
• Right/Left Atrium (Atria plural)
• Receives blood into the heart
• Right/Left Ventricle
• Pumps blood out of heart

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Internal Anatomy and Organization

• What separates the right side from the left side
  of the heart is the septum, in the heart oxygen
  rich and oxygen poor blood do not mix.
• To control the blood flow through the heart there
  are valves that control the movement of blood
  through the chambers and out of the heart.
• Atrioventricular (AV) valves open and close to
  move blood from the atria to the ventricles.
• Semilunar valves open and close to permit blood
  out of the heart.

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Pathway of Blood

• Blood arrives at the heart in the atriums
• Blood leaves the heart from the ventricles
• In from body to the Right Atrium (deoxygentated)
• Right atrium to right ventricle (deoxygentated)
• Right ventricle out to lungs (becomes oxygenated)
• Back from lungs to left atrium (oxygenated)
• Left atrium to left ventricle (oxygenated)
• Left Ventricle to body (oxygenated)

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Circulation

• Blood that has just picked up oxygen from the
  lungs comes into the heart and goes through the
  atrium and ventricles.
• Blood leaves the heart throughthe aorta which
  takes bloodout to the body.
• The aorta is the largest bloodvessel in the body.

Aorta
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Circulation

• When blood leaves the heart and goes to the lungs
  to pick up oxygen then returns to the heart this
  is known as the pulmonary circulation.
• When blood leaves the heart through the aorta and
  goes out to the body to drop off the oxygen and
  pick up waste products then returns it is known
  as the systemic circulation.

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Overview of the Cardiovascular System
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Introduction to Cardiovascular System

• Oxygen rich blood that is leaving the heart is
  carried through the arteries.
• Arteries carry blood away from the heart.
• Oxygen poor blood is carried in the veins from
  the body towards the heart.
• Veins carry blood towards the heart
• Capillaries network of blood vessels that
  connects the arteries and veins.
• Heart ? Artery ? Capillaries ? Veins ? Heart

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Blood Vessels

• The pressure in the blood vessels is highest in
  the arteries and lowest in the veins.
• To cause changes in the blood vessels pressure
  the vessels expand and contract.
• Using smooth muscle contractions.
• Muscles that cant be voluntarily controlled
  (organs)
• Veins also use a skeletal pump
• When muscle contractions push blood through the
  veins.
• Used to return blood from legs

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Blood Pressure

• Measurements by health professionals are made on
  the pressure in large arteries
• Systolicpressure during a heart contraction.
• Diastolicpressure when heart is relaxed
• Write systolic pressure first and diastolic last
  (120/80 mm Hg)
• Pressure in blood vessels decreases as distance
  from the heart increases.

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Blood Pressure

• Website

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Variations in Blood Pressure

• Normal human range is variable
• Normal
• 140110 mm Hg systolic
• 8075 mm Hg diastolic
• Hypotension
• Low systolic (below 110 mm HG)
• Often associated with illness
• Hypertension (High blood pressure)
• High systolic (above 140 mm HG)
• Can be dangerous if it is chronic

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High Blood Pressure

• When there is build up of fatty material in the
  blood vessels it causes the vessels and heart to
  have to work harder, and increased pressure in
  the vessels.
• This is a disease known as Arthrosclerosis
• If this type of blockage occurs in the blood
  vessels that supply oxygen to the heart muscles
  it can cause a Heart Attack.

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Stroke

• If a blockage occurs from a blood clot in the
  brain a stroke can occur.