Download Cardiovascular System Cardiovascular System The Heart The Heart

2/20/2016
Cardiovascular System
• Blood
• Heart
• Blood vessels
The Cardiovascular System
Part 1
Cardiovascular System
The Heart
• Functions
• Four separate chambers in humans
–Transport gases, wastes, food, hormones, blood cells
– Also other mammals, birds
• Systems affected
• Double pump
• 5 L/minute
–Respiratory
–Urinary
–Digestive
–Musculoskeletal
–Immune system
Capillary beds
of lungs where
gas exchange
occurs
Pulmonary
Circuit
Pulmonary arteries
Venae cavae
The Heart
• Symmetrical in design, but not in position
Pulmonary veins
Aorta and branches
– 2/3 of mass to the left of midline
– 1/3 to right
Left atrium
Left ventricle
Right atrium
Right ventricle
Oxygen-rich,
CO2-poor blood
Oxygen-poor,
CO2-rich blood
two closed circuits
Heart
Systemic
Circuit
Capillary beds of all
body tissues where
gas exchange occurs
Figure 18.5
1
2/20/2016
Located within mediastinum
Midsternal line
2nd rib
Sternum
Diaphragm
Point of
maximal
intensity
(PMI)
(a)
Superior
vena cava
Aorta
Parietal
pleura (cut)
Pulmonary
trunk
Left lung
Pericardium
(cut)
Apex of
heart
Diaphragm
(c)
Figure 18.1a
Pericardium
–Membrane surrounding and protecting the heart
• Confines while still allowing free movement
Pericardium
Figure 18.1c
Pericardium
–Double walled organ
• Fibrous pericardium
• Serous pericardium
Pericardium
–Double walled organ
–Double walled organ
• Fibrous pericardium
• Fibrous pericardium
• Serous pericardium
–Fibrous connective tissue
–Prevents overstretching, protection, anchorage
• Serous pericardium
–Serous epithelium
–Double layer
» Parietal layer
* Epithelial cells
* Secrete serous fluid (thin mucus)
* Fused to fibrous pericardium
» Visceral layer (epicardium)
* Thin connective tissue
* Forms surface of heart
2
2/20/2016
Pericardium
• Pericardial cavity
–Between visceral and parietal serous pericardium
–Scant amount of serous fluid – accumulation may cause…
• Pericarditis
–Inflammation of pericardium
–Sharp, stabbing chest pain
–May be caused by viral
infection, heart attack
–Begins suddenly but
resolves quickly
Muscular Wall of the Heart
Pulmonary
trunk
Pericardium
Myocardium
Fibrous pericardium
Parietal layer of
serous pericardium
Pericardial cavity
Epicardium
(visceral layer
Heart
of serous
wall
pericardium)
Myocardium
Endocardium
Heart chamber
• Three layers
–Epicardium
• Also called the…
–Myocardium
–Endocardium
Figure 18.2
Muscular wall of the heart
Pulmonary
trunk
Pericardium
Myocardium
Fibrous pericardium
Parietal layer of
serous pericardium
Pericardial cavity
Epicardium
(visceral layer
Heart
of serous
wall
pericardium)
Myocardium
Endocardium
Heart chamber
• Epicardium
– Serous membrane
– Typicially infiltrated
with fat in the elderly
Figure 18.2
3
2/20/2016
Muscular wall of the heart
Muscular wall of the heart
• Myocardium
• Myocardium
–Primarily cardiac muscle
–Bulk of heart
–Variable thickness
–Branching cardiac muscle cells
–Connected to one another by crisscrossing connective tissue
fibers
• Non-excitable – limits the spread of action potentials to specific
pathways in the heart
• Ventricles thicker than atria
• Left ventricle thicker than right
–Arranged in spiral or circular bundles
–Bundles interlace and effectively link all parts of the heart
together
– Inner surface raised into fingerlike projections
• Papillary muscles
Myocardium
Muscular wall of the heart
• Endocardium
–Squamous epithelium
• Smooth, white
Cardiac
muscle
bundles
–Continuous with
endothelial linings
of large blood
vessels
entering/exiting
the heart
Figure 18.3
Muscular wall of the heart
• Endocardium
Anatomy of the Heart
• Chambers
–Endocarditis – inflammation of the endocardium
–Common in IV drug users
– Leads to valve damage, emboli
4
2/20/2016
Anatomy of the Heart
Anatomy of the Heart
• Chambers
• Chambers
–Right and left atria
–Right and left ventricles
• Separated by interatrial septum
• Coronary sulcus (atrioventricular groove) encircles the junction of the
atria and ventricles
• Separated by interventricular septum
– Blood vessels that supply the myocardium rest inside
• Auricles
– Atrial appendages
– Increase atrial volume
Anatomy of the Heart
• Ventricular septal
defect (VSD)
Left
ventricle
Right
ventricle
Interventricular
septum
Figure 18.6
Major Vessels of the Heart
Major Vessels of the Heart
Brachiocephalic trunk
Superior vena cava
• Numerous blood vessels are associated with the
heart…
Right pulmonary
artery
Ascending aorta
Pulmonary trunk
Right pulmonary
veins
Left common carotid
artery
Left subclavian artery
Aortic arch
Ligamentum arteriosum
Left pulmonary artery
Left pulmonary veins
Auricle of
left atrium
Circumflex artery
Right atrium
Right coronary artery
(in coronary sulcus)
Anterior cardiac vein
Left coronary artery
(in coronary sulcus)
Left ventricle
Right ventricle
Right marginal artery
Small cardiac vein
Inferior vena cava
(b) Anterior view
Great cardiac vein
Anterior interventricular
artery (in anterior
interventricular sulcus)
Apex
Figure 18.4b
5
2/20/2016
Major Vessels of the Heart – Entering Right Atrium
Atria
Brachiocephalic trunk
The Receiving Chambers
Superior vena cava
Right pulmonary
artery
Ascending aorta
Pulmonary trunk
• Vessels entering right atrium
– Superior vena cava
– Inferior vena cava
– Coronary sinus
Right pulmonary
veins
Left common carotid
artery
Left subclavian artery
Aortic arch
Ligamentum arteriosum
Left pulmonary artery
Left pulmonary veins
Auricle of
left atrium
Circumflex artery
• Vessels entering left atrium
Right atrium
Right coronary artery
(in coronary sulcus)
Anterior cardiac vein
– Right and left pulmonary veins
Left coronary artery
(in coronary sulcus)
Left ventricle
Right ventricle
Right marginal artery
Small cardiac vein
Inferior vena cava
(b) Anterior view
Great cardiac vein
Anterior interventricular
artery (in anterior
interventricular sulcus)
Apex
Figure 18.4b
Major Vessels of the Heart – Entering Right Atrium
Major Vessels of the Heart – Entering Right Atrium
Aorta
Aorta
Left pulmonary
artery
Superior vena cava
Left pulmonary
veins
Auricle of left
atrium
Left atrium
Great cardiac
vein
Right pulmonary veins
Posterior vein
of left ventricle
Left ventricle
Apex
Superior vena cava
Right pulmonary artery
Right pulmonary
artery
Pulmonary trunk
Right atrium
Right atrium
Right pulmonary
veins
Fossa ovalis
Pectinate muscles
Inferior vena cava
Coronary sinus
Right coronary artery
(in coronary sulcus)
Posterior
interventricular
artery (in posterior
interventricular sulcus)
Middle cardiac vein
Right ventricle
(d) Posterior surface view
Tricuspid valve
Right ventricle
Chordae tendineae
Trabeculae carneae
Inferior vena cava
Left pulmonary
artery
Left atrium
Left pulmonary
veins
Mitral (bicuspid)
valve
Aortic valve
Pulmonary valve
Left ventricle
Papillary muscle
Interventricular
septum
Epicardium
Myocardium
Endocardium
(e) Frontal section
Figure 18.4d
Major Vessels of the Heart – Entering Left Atrium
Brachiocephalic trunk
Superior vena cava
Right pulmonary
artery
Ascending aorta
Pulmonary trunk
Right pulmonary
veins
Major Vessels of the Heart – Entering Left Atrium
Left common carotid
artery
Left subclavian artery
Aortic arch
Ligamentum arteriosum
Left pulmonary artery
Left pulmonary veins
Left coronary artery
(in coronary sulcus)
Left ventricle
Right ventricle
Small cardiac vein
Inferior vena cava
(b) Anterior view
Right pulmonary
artery
Pulmonary trunk
Right pulmonary
veins
Fossa ovalis
Pectinate muscles
Circumflex artery
Right marginal artery
Aorta
Superior vena cava
Right atrium
Auricle of
left atrium
Right atrium
Right coronary artery
(in coronary sulcus)
Anterior cardiac vein
Figure 18.4e
Great cardiac vein
Anterior interventricular
artery (in anterior
interventricular sulcus)
Apex
Tricuspid valve
Right ventricle
Chordae tendineae
Trabeculae carneae
Inferior vena cava
Left pulmonary
artery
Left atrium
Left pulmonary
veins
Mitral (bicuspid)
valve
Aortic valve
Pulmonary valve
Left ventricle
Papillary muscle
Interventricular
septum
Epicardium
Myocardium
Endocardium
(e) Frontal section
Figure 18.4b
Figure 18.4e
6
2/20/2016
Major Vessels of the Heart – Exiting Right Ventricle
Ventricles
Brachiocephalic trunk
The Discharging Chambers
Superior vena cava
Right pulmonary
artery
Ascending aorta
Pulmonary trunk
• Vessel leaving the right ventricle
– Pulmonary trunk → right and le> pulmonary arteries
• Vessel leaving the left ventricle
Right pulmonary
veins
– Aorta
Left common carotid
artery
Left subclavian artery
Aortic arch
Ligamentum arteriosum
Left pulmonary artery
Left pulmonary veins
Auricle of
left atrium
Circumflex artery
Right atrium
Right coronary artery
(in coronary sulcus)
Anterior cardiac vein
Left coronary artery
(in coronary sulcus)
Left ventricle
Right ventricle
Right marginal artery
Small cardiac vein
Inferior vena cava
(b) Anterior view
Great cardiac vein
Anterior interventricular
artery (in anterior
interventricular sulcus)
Apex
Figure 18.4b
Major Vessels of the Heart – Exiting Right Ventricle
Brachiocephalic trunk
Superior vena cava
Right pulmonary
artery
Ascending aorta
Pulmonary trunk
Right pulmonary
veins
Major Vessels of the Heart – Exiting Right Ventricle
Left common carotid
artery
Left subclavian artery
Aortic arch
Ligamentum arteriosum
Left pulmonary artery
Left pulmonary veins
Right pulmonary
veins
Fossa ovalis
Pectinate muscles
Circumflex artery
Left coronary artery
(in coronary sulcus)
Left ventricle
Right ventricle
Right marginal artery
Small cardiac vein
Inferior vena cava
(b) Anterior view
Right pulmonary
artery
Pulmonary trunk
Right atrium
Auricle of
left atrium
Right atrium
Right coronary artery
(in coronary sulcus)
Anterior cardiac vein
Aorta
Superior vena cava
Great cardiac vein
Anterior interventricular
artery (in anterior
interventricular sulcus)
Apex
Tricuspid valve
Right ventricle
Chordae tendineae
Trabeculae carneae
Inferior vena cava
Left pulmonary
artery
Left atrium
Left pulmonary
veins
Mitral (bicuspid)
valve
Aortic valve
Pulmonary valve
Left ventricle
Papillary muscle
Interventricular
septum
Epicardium
Myocardium
Endocardium
(e) Frontal section
Figure 18.4b
Major Vessels of the Heart – Exiting Left Ventricle
Brachiocephalic trunk
Superior vena cava
Right pulmonary
artery
Ascending aorta
Pulmonary trunk
Right pulmonary
veins
Major Vessels of the Heart – Exiting Left Ventricle
Left common carotid
artery
Left subclavian artery
Aortic arch
Ligamentum arteriosum
Left pulmonary artery
Left pulmonary veins
Left coronary artery
(in coronary sulcus)
Left ventricle
Right ventricle
Small cardiac vein
Inferior vena cava
(b) Anterior view
Right pulmonary
artery
Pulmonary trunk
Right pulmonary
veins
Fossa ovalis
Pectinate muscles
Circumflex artery
Right marginal artery
Aorta
Superior vena cava
Right atrium
Auricle of
left atrium
Right atrium
Right coronary artery
(in coronary sulcus)
Anterior cardiac vein
Figure 18.4e
Great cardiac vein
Anterior interventricular
artery (in anterior
interventricular sulcus)
Apex
Tricuspid valve
Right ventricle
Chordae tendineae
Trabeculae carneae
Inferior vena cava
Left pulmonary
artery
Left atrium
Left pulmonary
veins
Mitral (bicuspid)
valve
Aortic valve
Pulmonary valve
Left ventricle
Papillary muscle
Interventricular
septum
Epicardium
Myocardium
Endocardium
(e) Frontal section
Figure 18.4b
Figure 18.4e
7
2/20/2016
Major Vessels of the Heart
Coronary Arteries
Left common carotid
artery
Left subclavian artery
Aortic arch
Ligamentum arteriosum
Brachiocephalic trunk
Superior vena cava
• Supply blood to the heart wall itself
Right pulmonary
artery
Ascending aorta
Pulmonary trunk
Left pulmonary artery
Left pulmonary veins
Right pulmonary
veins
Auricle of
left atrium
Circumflex artery
Right atrium
Left coronary artery
(in coronary sulcus)
Right coronary artery
(in coronary sulcus)
Anterior cardiac vein
Left ventricle
Right ventricle
Great cardiac vein
Right marginal artery
Anterior interventricular
artery (in anterior
interventricular sulcus)
Small cardiac vein
Inferior vena cava
Apex
(b) Anterior view
Figure 18.4b
Heart Valves
Pulmonary
valve
Aortic
valve
Area of
cutaway
Mitral
valve
Tricuspid
valve
• Atrioventricular (AV) valves
– Prevent backflow into the atria when ventricles contract
– Chordae tendineae (“heart strings”) anchor AV valve cusps to
papillary muscles
• Semilunar valves
– Prevent backflow into the ventricles when ventricles relax
Unidirectional blood flow through the heart
Chordae tendineae
attached to tricuspid valve flap
(c)
Papillary
muscle
Figure 18.8c
Heart Valves
Aorta
Superior vena cava
• Atrioventricular
–Separate atria from ventricles
• Tricuspid
– Right side
• Mitral (bicuspid)
– Left side
• Semilunar
– Separate ventricles from great arteries
• Pulmonary semilunar
• Aortic semilunar
Right pulmonary
artery
Pulmonary trunk
Right atrium
Right pulmonary
veins
Fossa ovalis
Pectinate muscles
Tricuspid valve
Right ventricle
Chordae tendineae
Trabeculae carneae
Inferior vena cava
Left pulmonary
artery
Left atrium
Left pulmonary
veins
Mitral (bicuspid)
valve
Aortic valve
Pulmonary valve
Left ventricle
Papillary muscle
Interventricular
septum
Epicardium
Myocardium
Endocardium
(e) Frontal section
Figure 18.4e
8
2/20/2016
Pulmonary valve
Aortic valve
Tricuspid
Area of cutaway
(right atrioventricular)
Mitral valve
valve
Tricuspid valve
Mitral
(left atrioventricular)
valve
Aortic
valve
Cardiac Circulation
Myocardium
Fibrous
skeleton
(a)
– Right side = pulmonary circuit
Tricuspid
(right atrioventricular)
valve
Mitral
(left atrioventricular)
valve
Aortic valve
Pulmonary
valve
Pulmonary valve
Aortic valve
Area of cutaway
• The heart is two side-by-side pumps
Myocardium
(b)
• Vessels that carry blood to and from the lungs
– Left side = systemic circuit
• Vessels that carry the blood to and from all body tissues
Pulmonary
valve
Mitral valve
TricuspidAnterior
valve
Figure 18.8a
Capillary beds
of lungs where
gas exchange
occurs
Pulmonary
Circuit
Pulmonary arteries
Venae cavae
Pathway of Blood Through the Heart
Pulmonary veins
Aorta and branches
Right atrium (via vena cava)
Lungs
Tricuspid valve
Pulmonary veins
Right ventricle
Left atrium
Pulmonary semilunar valve
Bicuspid valve
Left atrium
Left ventricle
Right atrium
Right ventricle
Heart
Systemic
Circuit
Pulmonary trunk
Pulmonary arteries
Oxygen-rich,
CO2-poor blood
Oxygen-poor,
CO2-rich blood
Capillary beds of all
body tissues where
gas exchange occurs
Lungs
Left ventricle
Aortic semilunar valve
Aorta
Systemic circulation
Figure 18.5
1 Blood returning to the
heart fills atria, putting
pressure against
atrioventricular valves;
atrioventricular valves are
forced open.
Direction of
blood flow
Aorta
Atrium
Cusp of
atrioventricular
valve (open)
2 As ventricles fill,
atrioventricular valve flaps
hang limply into ventricles.
Chordae
tendineae
3 Atria contract, forcing
additional blood into ventricles.
Ventricle
Papillary
muscle
(a) AV valves open; atrial pressure greater than ventricular pressure
Pulmonary
trunk
As ventricles
contract and
intraventricular
pressure rises,
blood is pushed up
against semilunar
valves, forcing them
open.
(a) Semilunar valves open
Atrium
1 Ventricles contract, forcing
blood against atrioventricular
valve cusps.
Cusps of
atrioventricular
valve (closed)
2 Atrioventricular valves
close.
Blood in
ventricle
3 Papillary muscles
contract and chordae
tendineae tighten,
preventing valve flaps
from everting into atria.
As ventricles relax
and intraventricular
pressure falls, blood
flows back from
arteries, filling the
cusps of semilunar
valves and forcing
them to close.
(b) Semilunar valves closed
(b) AV valves closed; atrial pressure less than ventricular pressure
Figure 18.9
Figure 18.10
9
2/20/2016
Heart Sounds
• “lub-dup”
Coronary (Cardiac) Circulation
• Blood from the chambers cannot serve as a functional blood
supply to the heart
• Heart muscle has its own blood supply
– Coronary circulation
Coronary (Cardiac) Circulation
• Arteries
– Right and left coronary arteries
– Branch off base of the aorta
– Extensive branching throughout epicardium
• Common for branches from right and left coronary arteries to unite
– Anastomoses
• Cardiac veins feed into coronary sinus
directly into right atrium
10
2/20/2016
Aorta
Pulmonary
trunk
Superior
vena cava
Left atrium
Anastomosis
(junction of
vessels)
Right
atrium
Left
coronary
artery
Circumflex
artery
Right
coronary
Left
artery
ventricle
Right
ventricle
Anterior
Right
interventricular
marginal Posterior
artery
artery
interventricular
artery
(a) The major coronary arteries
Aorta
Left pulmonary
artery
Superior vena cava
Left pulmonary
veins
Auricle of left
atrium
Left atrium
Great cardiac
vein
Right pulmonary veins
Posterior vein
of left ventricle
Left ventricle
Apex
Right pulmonary artery
Right atrium
Inferior vena cava
Coronary sinus
Right coronary artery
(in coronary sulcus)
Posterior
interventricular
artery (in posterior
interventricular sulcus)
Middle cardiac vein
Right ventricle
(d) Posterior surface view
Figure 18.7a
Figure 18.4d
Coronary sinus drains into right atrium
Collateral Circulation
Superior
vena cava
Anterior
cardiac
veins
• Benefits of anastomoses
• Provides additional route of blood flow
• Older heart attack patients are more likely to survive
than younger ones
Great
cardiac
vein
– Sudden clot formation vs gradual
Coronary
sinus
Small cardiac vein
Middle cardiac vein
(b) The major cardiac veins
Figure 18.7b
11