Download PowerPoint - Delmar

Chapter 13
HEART
FUNCTIONS OF THE
CIRCULATORY SYSTEM
• Heart pumps and circulates blood to
all parts of the body
• Blood vessels circulate blood
between heart and cells
• Blood carries oxygen and nutrients
to cells and carries away wastes
• Lymph system returns excess fluids
from tissues and makes lymphocytes
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
ORGANS OF THE
CIRCULATORY SYSTEM
•
•
•
•
•
•
Heart
Arteries
Veins
Capillaries
Blood
Lymphatic system
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
MAJOR BLOOD CIRCUITS
• Blood leaves the heart through
arteries and returns to the heart
from veins
• The general (systemic) circulation
carries blood throughout the body
• Cardiopulmonary circulation carries
blood from the heart to lungs and
back
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
THE HEART
• The heart is the main organ
responsible for circulating the
blood throughout the body
efficiently
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
THE HEART
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
STRUCTURE OF THE HEART
• The heart is a hollow, muscular,
double pump
– Pericardium - double layer of fibrous
tissues surrounding heart
– Myocardium - cardiac muscle tissue
– Endocardium - Smooth inner lining
– Septum - Muscular wall separating
heart into two halves
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
STRUCTURE OF THE HEART
• Structures leading to and from the
heart:
– Vena cava
• superior and inferior
– Coronary sinus
– Pulmonary artery
– Pulmonary veins
– Aorta
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
STRUCTURE OF THE HEART
• Four chambers of the heart
– Right atrium
– Left atrium
– Right ventricle
– Left ventricle
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
STRUCTURE OF THE HEART
• Four valves permit blood flow in
only one direction
– Tricuspid valve
– Bicuspid (mitral) valve
– Pulmonary semilunar valve
– Aortic semilunar valve
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
STRUCTURE OF THE HEART
• Two major functions occur with
each heart beat
– Right heart: Blood is taken to the
lungs for oxygen
– Left heart: Blood is taken from lungs
to be circulated throughout body
• The heart receives its blood supply
from the coronary artery
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
STRUCTURE OF THE HEART
• Stroke volume:
– Number of heart beats per minute
– The heart at rest beats between 72
and 80 times per minute
• Cardiac output:
– The amount of blood ejected from
heart per minute
– Between 60 and 80 ml of blood on
average
© 2004
Delmar Learning, a Division of Thomson Learning, Inc.
STRUCTURE OF THE HEART
• Lubb dupp sounds - Sounds made by
the valves during the cardiac cycle
– Lubb - sound made when the tricuspid
and bicuspid valves close between the
atria and ventricles
– Dupp - Caused by semilunar valves in
the aorta and the pulmonary artery
closing
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
CONTROL OF HEART
CONTRACTIONS
• Pacemaker (sinoatrial node)
– Conducting cells found at the opening
of the superior vena cava that control
heart muscle contractions
– Sends out electrical impulses that
begin and regulate the heart
• Electrocardiogram (ECG or EKG)
– Records electrical activity of heart
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
DIAGNOSTIC TESTS FOR HEART
AND CIRCULATORY FUNCTION
• Cardiac catheterization is the
insertion of a catheter into the
femoral artery or vein
– Dye is inserted and pictures are taken
as fluid moves through the heart
• Stress tests determine how
physiological stress and exercise
affect the heart
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
DISEASES OF THE HEART
• Common symptoms of heart disease
– Arrhythmia
– Bradycardia
– Tachycardia
– Murmurs
– Mitral valve prolapse
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
DISEASES OF THE HEART
• Coronary Artery disease (CAD)
– Narrowing of the arteries that supply
oxygen and nutrients to the heart
– Angina pectoris - severe chest pain
from inadequate oxygen to heart
– Myocardial infarction (heart attack) caused by lack of blood supply to
heart
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
DISEASES OF THE HEART
• Infectious diseases of the heart
– Pericarditis
– Myocarditis
– Endocarditis
– Rheumatic heart disease
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
DISEASES OF THE HEART
• Prevention of heart disease
– Not smoking
– Regular exercise
– Maintaining ideal weight
– Estrogen replacement therapy
– Reduction of triglyceride and
cholesterol levels
– Maintaining normal blood pressure
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
DISEASES OF THE HEART
• Congestive heart failure is similar
to heart failure but includes edema
in lower extremities
• Rhythm/Conduction defects
– Heart block
– Premature contractions
– Fibrillation
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
TYPES OF HEART SURGERY
•
•
•
•
Angioplasty (balloon surgery)
Coronary bypass
Cardiac stints
Transmyocardial laser
revascularization (TMR)
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.
HEART TRANSPLANTS
• Heart transplant is needed when
individual’s heart can no longer
function properly
• Organ rejection may occur even
when tissue type is matched
• Immunosuppressants are drugs
used to suppress recipient’s immune
system from rejecting donor organ
© 2004 Delmar Learning, a Division of Thomson Learning, Inc.