Heart

Front 1

thoracic cavity

Back 1

contains:
pleural cavities
mediastinum

Front 2

middle mediastinum (pericardial cavity)

Back 2

-region between anterior and posterior mediastinum
-located between pleural cavities
-contains: pericardium, heart, origins of vessels, various nerves, smaller vessels

Front 3

fibrous pericardium

Back 3

-outer layer of pericardium
-made of tough connective tissue
-continuous with adventitia of greater vessels and attached to central tendon of the diaphragm and sternum
-pain conveyed by sensory fibers of phrenic nerve

Front 4

serous peridcardium

Back 4

Two layers:
-parietal layer: lines inner surface of fibrous pericardium
-visceral layer (epicardium): adheres to and forms outer covering of of heart,

Front 5

Cardiac Tamponade

Back 5

"heart compression"
-collection of blood in the pericardial cavity, preventing heart from expanding fully
-results from: trauma, bleeding from weak muscle after a heart attack, bleeding after cardiac surgery
-signs: jugular vein distension, muffled heart sounds, narrowing of difference between systolic and diastolic pressures
-treatment: pericardiocentesis (drainage of fluid from pericardial cavity by insertion of needle into intercostal space near xyphoid process of sternum)

Front 6

ventricular wall of heart (histology slide)

Back 6

epicardium:
-tunica adventitia of heart
-composed of epithelial cells, connective tissue, and fat
-secretes serous fluid
-contains coronary vessels and autonomic nerves
-surrounded by pericardial cavity (potential space)
myocardium
-tunica media of heart
-composed of cardiac muscles
endocardium
-tunica intima of heart
-composed of epithelial cells and connective tissue
-contains blood vessels, nerves, and conducting systems

Front 7

Sulci of the heart

Back 7

coronary (atrioventricular) sulcus: -encircles heart, dividing atria from ventricles
anterior and posterior interventricular sulci:
-separate the two ventricles

Front 8

Right coronary artery
(branches and supply)

Back 8

branches:
1. branch to SA node
2. marginal branch
3. posterior interventricular artery
Supplies:
-R atrium
-R ventricle
-SA node
-AV nodes
-Interatrial septum
-L atrium (part)
-IV septum (part)
-L ventricle (part)

Front 9

Left coronary artery

Back 9

branches:
1. anterior interventricular artery (left anterior descending)
2. circumflex branch
3. marginal branch
supplies:
-L atrium (mostly)
-L ventricle (mostly)
-IV septum (mostly)
-AV bundle/branches

Front 10

Clinically important coronary arteries

Back 10

Right coronary artery-supplies posterior heart
Left anterior descending artery (ant. interventricular artery)-supplies septum and anterior heart
-circumflex artery-supplies lateral heart

Front 11

cardiac veins

Back 11

drain into coronary sinus:
-great cardiac veins, middle cardiac vein, small cardiac vein, posterior cardiac vein
drain into right atrium:
-coronary sinus, anterior cardiac veins of RV, venae cordis minimae

Front 12

Right Atrium

Back 12

entry point for deoxygenated blood from: superior and inferior vena cava, coronary sinus, other cardiac veins
major structures:
-right appendage
-sinus venarum
-pectinate muscles
-crista terminalis (transition between pectinate muscles and sinus venarum)
-fossa ovalis
-opening of coronary sinus

Front 13

Right Ventricle

Back 13

major structures:
-trabeculae carneae (muscle)
-moderator band (carries conduction)
-septal limb
-septomarginal trabecula=moderator band + septal limb
-supraventricular crest
-chordae tendineae
-papillary muscles
-tricuspid valve (prevents backflow to R atrium)

Front 14

tricuspid valve

Back 14

atrioventricular valve
structure:
composed of 3 cusps (leaflets) attached to papillary muscles via chordae tendinae to prevent eversion of valves
Papillary muscles:
1. Septal
2. Posterior
3. Anterior

Front 15

Pulmonary Valve

Back 15

separates pulmonary veins from L atrium
structure:
semilunar valve with 3 semilunar cusps (left, anterior, right)

Front 16

Left Atrium

Back 16

entry point for oxygenated blood returning to the heart from the lungs via the pulmonary veins
major structures:
-pulmonary valve
-valve of foramen ovale

Front 17

mitral (bicuspid) valve

Back 17

atrioventricular (AV) valve
prevents back flow of blood from L ventricle into L atrium
structure:
composed of 2 cusps (anterior, posteror) attached to papillary muscles via chordae tendineae
papillary muscles:
1. anterior
2. posterior

Front 18

Left Ventricle

Back 18

blood enters from right ventricle and then is pushed out into circulation
major structures:
-interventricular septum: muscular and membranous parts
-papillary muscles
-trabeculae carneae
thicker wall compared to R ventricle (needs more muscle to push blood out against higher pressure)

Front 19

Aortic valve

Back 19

a semilunar valve
structure:
-composed of 3 semilunar cusps (right, posterior, left)
prevents backflow of blood from aorta back into left ventricle

Front 20

Left ventricular hypertrophy

Back 20

-enlargement of muscles of heart
-NON-tumorous increase in size of cells NOT cell number,
causes: systemic hypertension and aortic/mitral valvular disease

Front 21

Myocardial infarction (MI)

Back 21

necrosis resulting in ischemia cause by obstruction of blood supply to region of heart
"white infarct": caused by arterial occlusion in heart, spleen, or kidney
"red infarct": RBCs leak into necrotic area as in lung/GI
Types:
1. Transmural-traversing entire ventricular wall from endocardium to epicardium
2. Subendocardial-limited to interior 1/3 of ventricular wall

Front 22

Cardiac Skeleton

Back 22

-collection of dense, fibrous connective tissue in form of 4 rings
-helps maintain integrity of valves
-attachment site for cusps
-separates atrial and ventricular musculature
-electrically isolates atria from ventricles

Front 23

Heart sounds

Back 23

S1 (first sound) LUB- tricuspid and mitral valve closure
S2 (second sound) DUB- pulmonary and aortic valve closure

Front 24

Auscultatory locations

Back 24

heart sounds best heard in locations peripheral to where the actual valves are located due to bloodflow carrying sound
Pulmonary valve: Left 2nd intercostal space just lateral to sternum
Tricuspid valve: lower part of sternum
Aortic valve: right 2nd intercostal space just lateral to sternum
Mitral valve: Left 5th intercostal space away from sternum

Front 25

Stenosis

Back 25

narrowing
Types:
Pulmonary valve stenosis:
-valve cusps fused/damaged, cannot close and form small opening
-restricts right ventricular outflow
Mitral valve stenosis:
-most frequently diseased valve
-nodules on cusps cause turbulent backflow
Aortic valve stenosis:
-defective valve
-results in regurgitation

All diagnosed by a heart murmer

Front 26

conducting system of heart

Back 26

-can initiate and coordinate contraction of musculature of atria and ventricles spontaneoustly
sequence of conduction:
1. SA node (pacemaker)-->2. AV node--> 3R/L AV bundle (of His)--> 4. Purkinje fibers

Front 27

Innervation to the Heart

Back 27

Heart rate modified by autonomic nervous system (ANS)
Cardiac plexus
-collection of sympathetic and parasympathetic nerves located at bifurcation of trachea just superior to heart
-sends nerve fibers along coronary arteries to reach heart
-modifies heart rate, force of contraction, and cardiac output

Front 28

Cardiac plexus

Back 28

Sympathetic nerves
-come from sympathetic chain: Superior, middle, and inferior cervical cardiac nerves, thoracic cardiac nerves
-visceral motor fibers: RAISE heart rate and force of contraction
-visceral sensory fibers: convey cardiac pain signals
Parasympathetic nerves
-come from vagus nerve (cranial nerve X)
-visceral motor fibers: LOWER heart rate and force of contraction
-visceral sensory fibers: transmit cardiac reflexes (alterations in BP and blood chemistry)