Transcript Cardiovasular-Heart-2404heart02-22-07

Heart
Figure 22.02b
Heart
Functions of the Heart
Ensures
unidirectional flow
of blood
Pumps blood to
lungs and body
Develops blood
pressure for
nutrient and waste
exchange
Figure 22.01
Heart-Anatomical Location and Orientation
Heart Anatomical Orientation and Location
Chambers of the Heart
• Atria
• (Left and
Right)
• Ventricles
(Left and
Right)
Heart Valves
• Atrioventricular
(AV) valves –
between atria
and ventricles
• Semilumar
Valves– between
ventricles and
great arteries
Valves of the Heart
Heart Valves
Figure 18.8a
Atrioventricular Valves (Open)
Atrioventricular Valves (Closed)
Figure 18.9b
Semilunar Valves (Open vs Closed)
Figure 18.10a, b
Pericardium
Layers of the Heart
Layers of the Heart
Epicardium
Myocardium
Endocardium
Figure 18.3
Cardiac Muscle Cells
Cardiac Muscle Cells
Blood Flow Through the Heart
Figure 22.06ab
Conduction System
• Cardiac muscle tissue has intrinsic ability
to:
• Generate and conduct impulses
• Signal these cells to contract rhythmically
• Conducting system
• A series of specialized cardiac muscle cells
• Sinoatrial (SA) node sets the inherent rate of
contraction
Conducting System
Figure 18.12
Conduction System
Conduction System and ECGs
Conduction System of Heart
Disorders of the Heart
• Coronary artery disease
• Atherosclerosis – fatty deposits
• Angina pectoris – chest pain
• Myocardial infarction – blocked
coronary artery
• Silent ischemia – no pain or warning
Disorders of the Heart
• Heart failure
• Progressive weakening of the heart
• Cannot meet the body’s demands for
oxygenated blood
• Congestive heart failure – heart
enlarges
• Pumping efficiency declines
• Cor pulmonale
• Enlargement and potential failure of
the right ventricle
Disorders of Conduction
• Ventricular fibrillation
• Rapid, random firing of electrical
impulses in the ventricles
• Atrial fibrillation
• Multiple waves of impulses randomly
signal the AV node
• Signals ventricles to contract quickly
and irregularly