Cardiovascular System
Cardiovascular System
• Two divisions
Cardiovascular System
• Two divisions: pulmonary
Cardiovascular System
• Two divisions: pulmonary & systemic
Cardiovascular System
• Pulmonary Division
–Blood flows from heart
Cardiovascular System
• Pulmonary Division
–Blood flows from heart to alveolar capillaries
Cardiovascular System
• Pulmonary Division
–Blood flows from heart to alveolar capillaries and back to heart
Cardiovascular System
• Systemic Division
Cardiovascular System
• Systemic Division
– Blood flows from heart
Cardiovascular System
• Systemic Division
– Blood flows from heart to all tissue capillaries
Cardiovascular System
• Systemic Division
– Blood flows from heart to all tissue capillaries (except alveolar capillaries)
Cardiovascular System
• Systemic Division
– Blood flows from heart to all tissue capillaries (except alveolar capillaries) and back to heart
• Pulmonary arteries carry blood:
• Pulmonary arteries carry blood:
High in O2, low in CO2
• Pulmonary arteries carry blood:
High in O2
Low in O2 Low in O2 high in CO2
High in O2, low in CO2
• Heart
– Location
• Heart
– Location: mediastinum
• Heart
– Location: mediastinum
• Heart
– Location: mediastinum
– Size?
• Pericardium: protective sac surrounding the heart
• Pericardium: protective sac surrounding the heart
• Pericardium: protective sac surrounding the heart
–Visceral pericardium
• Pericardium: protective sac surrounding the heart
–Visceral pericardium
– Parietal pericardium
• Pericardium: protective sac surrounding the heart
–Visceral pericardium
– Parietal pericardium
• Layers of the heart wall
• Layers of the heart wall
– endocardium
• Layers of the heart wall
– endocardium
– myocardium
• Layers of the heart wall
– endocardium
– myocardium
• Layers of the heart wall
– endocardium
– myocardium
– epicardium
• Layers of the heart wall
– endocardium
– myocardium
– epicardium (same as the visceral pericardium)
• Chambers of the heart
• Chambers of the heart
– Receiving chambers:
• Chambers of the heart
– Receiving chambers: atria
• Chambers of the heart
– Receiving chambers: atria (singular:
• Chambers of the heart
– Receiving chambers: atria (singular: atrium)
• Chambers of the heart
– Receiving chambers: atria (singular: atrium)
• Chambers of the heart
– Receiving chambers: atria (singular: atrium)
–Pumping chambers: ventricles
• Right ventricle
• Right ventricle: pump for the pulmonary circulation
• Right ventricle: pump for the pulmonary circulation
• Left ventricle
• Right ventricle: pump for the pulmonary circulation
• Left ventricle: pump for the systemic circulation
• “Great Vessels” of the Heart
– Aorta
– Pulmonary Trunk
Inferior vena cava
Superior vena cava Pulmonary
trunk
Pulmonary veinsAorta
RPALPA
• Heart valves: ensure one-way flow of blood through heart
– Semilunar valves
– Semilunar valves
• pulmonary semilunar
– Semilunar valves
• pulmonary semilunar
• aortic semilunar
• Atrio-ventricular (AV) valves
• Atrio-ventricular (AV) valves
• tricuspid
• Atrio-ventricular (AV) valves
• tricuspid
• bicuspid
• Atrio-ventricular (AV) valves
• tricuspid
• bicuspid (mitral)
• Atrio-ventricular (AV) valves
• tricuspid
• bicuspid (mitral) Associated with papillary
muscles
• Atrio-ventricular (AV) valves
• tricuspid
• bicuspid (mitral) Associated with papillary
muscles and chordae tendinae
• Skeleton of the heart
– set of 4 fibrous rings near base of heart
• Skeleton of the heart, con’t.
– provides rigidity to prevent the dilation of valves
– provides a point of attachment for valves
• Skeleton of the heart, con’t.
– electrically isolates the atria from the ventricles.
•The A-V bundle (“bundle of His”) is the only electrical connection between the atria and the ventricles
• Path of Blood Flow Through the Heart
http://www.innerbody.com/anim/heart.html
• Heart Sounds
–1st sound (“lub”)
• closing of the AV valves
– 2nd sound (“dup”)
• closing of the semilunar valves
• Heart Sounds
–1st sound (“lub”)
• closing of the AV valves
– 2nd sound (“dup”)
• closing of the semilunar valves
Conduction System of the Heart
Sinoatrial node
Atrioventricular node
AV bundle
Purkinje fibers
Bundle branches
• Blood Vessels
1. Arteries
2. Arterioles
3. Capillaries
4. Venules
5. Veins
• All blood vessels are lined with endothelium
1. Arteries
• Carry blood away from the heart
• Subject to the highest blood pressure
1. Arteries
• Carry blood away from the heart
• Subject to the highest blood pressure
1. Arteries
• Carry blood away from the heart
• Subject to the highest blood pressure
• Located deep
– Structure of Arteries
•Tunica interna
•Tunica media
•Tunica externa
• Types of arteries
– Elastic arteries
• Contain elastic fibers in the tunica media and interna
•Largest arteries
• Types of arteries
– Muscular arteries• Little elasticity• Abundant smooth muscle in tunica media
2. Arterioles
• < 1mm in diameter
• Endothelium and smooth muscle
2. Arterioles
• < 1mm in diameter
• Endothelium and smooth muscle
2. Arterioles
• < 1mm in diameter
• Endothelium and smooth muscle
• Metarterioles regulate flow of blood into capillaries
2. Arterioles• < 1mm in diameter• Endothelium and smooth
muscle • Metarterioles regulate flow
of blood into capillaries • Help regulate blood
pressure
3. Capillaries• Sites of exchange
exchange between blood and tissue cells in systemic caps
exchange between blood and air in pulmonary caps
• Very permeable
4. Veins
• Return blood back towards heart
• Smallest veins: venules
• Veins have 3 layers like arteries
• Differences between arteries and veins
– thinner
– larger diameter
– located both deep and superficial
– veins have valves
Distribution of Blood
• Coronary Circulation
– Blood flow to and from the myocardial capillaries
• Some vessels of the coronary circuit– Right coronary artery– Left coronary artery
• circumflex• anterior interventricular (also: LAD)
– Coronary sinus
• Hepatic Portal Circulation
• Features of fetal heart
– Foramen ovale
– Ductus arteriosus
• Other features of fetal circulation
– Umbilical arteries and veins
– Ductus venosus
• Changes in fetal circulation after birth
– foramen ovale closes
– ductus arteriosus closes
Coronary Artery Disease
• Degenerative changes in coronary arteries
• Often associated with arterial plaques