Heart LOs outline

Question 1

parasympathetic fibers, which

Answer 1

decrease the heart rate and constrict the coronary arteries.

Vagus nerve – (+) slows HR, reduces the force contraction, constricts the CAs

Question 2

sympathetic fibers, which

Answer 2

increase the heart rate and the force of the heartbeat and cause dilation of the coronary arteries

T1-T4 – sensory afferent and efferent fibers – (+) increased HR, impulse conduction, force of contraction, incr blood flow thru CAs

Question 3

Sinoatrial node:

Answer 3

• specialized cardiac fibers that lies in myocardium at the upper end of crista terminalis near the opening of the SVC in the right atrium
• pacemaker of heart, initiates heartbeats, altered by autonomic stimulation
• impulses spread by cardiac muscle in the right atrium to AV node
• SUPPLIED BY SINUS NODE ARTERY

Question 4

AV node:

Answer 4

• lies in septal wall of right atrium, receives stimulus from SA node, sends it to AV bundle
• supplied by AV node artery
• innervated by autonomic nerve fibers

Question 5

AV Bundle:

Answer 5

• begins at AV node , runs along membranous part of interventricular septum
• splits into right and left bundles, break up in muscular part of interventricular septum, break up into purkinje fibers

Question 6

Pulmonary Valve:

Answer 6

• behind medial end of third costal cartilage
• shuts after closure of aortic valve
• most audible left second intercostal space

Question 7

Aortic Valve:

Answer 7

• lies behind left half of sternum, opposite third intercostal space
• closed during ventricular diastole (dub heart sound)
• most audible over right second intercostal space

Question 8

Tricuspid Valve:

Answer 8

-lies behind right atrium and ventricle, behind right half of sternum, covered by endocardium
-anterior,posterior and septal cusps , attached by chordae tendinae to three papillary muscles,
Keep valve closed against pressure of pumping heart
-closed during contracture
-auscultate over right lower part of the sternum

Question 9

Bicuspid Valve:

Answer 9

• Between left atrium and left ventricle, behind left half of sternum
• 2 cusps, larger anterior and small posterior
• closed slightly before tricuspid valve
• auscultate at left fifth intercostal space

Question 10

fibrous (membranous) portion

of septa

Answer 10

• superior and posterior – thin membrane, part of fibrous skeleton of heart – septal cusp of tricuspid is attached to this membranous part

Question 11

muscular portion

of septa

Answer 11

-inferior and bulges into RV – forms majority of the septum, thicker d/t high pressure of LV

Question 12

Coronary Sulcus

Answer 12

marks border between atria and ventricles

Question 13

Sulcus Terminalis

Answer 13

a groove on the external surface of the right atrium, marks the junction of the primitive sinus venosus with the atrium in the embryo and corresponds to a ridge on the internal heart surface, the crista terminalis

Question 14

chordae tendineae

Answer 14

prevent leakage of blood into right atrium

Question 15

-Septomarginal trabecula

Answer 15

band of trabeculae that forms a bridge between intraventricular septum and the base of the anterior papillary muscle of the right ventricle
-prevents overdistention of ventricle, carries right limb of AV bundle from septum to wall of ventricle

Question 16

IV Septum

Answer 16

origin of septal papillary muscle

Question 17

Azygos Vein

Answer 17

-The azygos vein is a vein running up the side of the thoracic vertebral column draining itself towards the superior vena cava. It connects the systems of superior vena cava and inferior vena cava and can provide an alternative path for blood to the right atrium when either of the venae cavae is blocked

Question 18

Pulmonary Trunk:

Answer 18

Arises from the conus arteriosus of the right ventricle, passes obliquely upward and backward across the origin and on the left side of the ascending aorta within the fibrous pericardium, and bifurcates into the right and left pulmonary arteries in the concavity of the aortic arch.

Question 19

Superior vena cava:

Answer 19

• Is formed by the union of the right and left brachiocephalic veins and returns blood from all structures superior to the diaphragm, except the lungs and heart
• Descends on the right side of the ascending aorta, receives the azygos vein, and enters the right atrium. Its upper half is in the superior mediastinum, and its lower half is in the middle mediastinum.

Question 20

Arch of the Aorta:

Answer 20

• in superior mediastinum, continuation of ascending aorta, arches over right pulmonary artery and left main bronchus
• Gives rise to the brachiocephalic, left common carotid, and left subclavian arteries

Question 21

Ascending Aorta:

Answer 21

• comes from left ventricle and ascends behind sternum to end at level of sternal angle
• lies in middle mediastinum, gives of right and left coronary artery

Question 22

Smallest Cardiac Vein:

Answer 22

-Begin in the wall of the heart and empty directly into its chambers.

Question 23

Anterior Cardiac Vein:

Answer 23

-drains anterior right ventricle, ends in right atrium

Question 24

Oblique vein of Left Atrium:

Answer 24

-descends to empty into coronary sinus

Question 25

Middle Cardiac Vein:

Answer 25

- begins at apex of heart, accompanies right coronary artery | - drains into right end of coronary sinus

Question 26

Great Cardiac Vein:

Answer 26

- begins at Apex of heart, ascends along left coronary artery - continues through coronary sulcus as coronary sinus

Question 27

Coronary Sinus:

Answer 27

- lies in coronary sulcus, separates atria from ventricles - largest vein draining the heart, opens into right atrium between IVC and AC - receives great, middle and small cardiac veins, oblique vein and posterior vein

Question 28

Right coronary artery and branches:

Answer 28

- arises from sinus of ascending aorta, runs between pulmonary trunk and right auricle, supplies right atrium and ventricle - SA Nodal Artery: encircles base of SVC, supplies SA node and right atrium - Marginal Artery: supplies inferior margin of right ventricle - Posterior descending artery: supplies party of IV septum, left ventricle, AV node - AV nodal artery: supplies AV node

Question 29

Left coronary artery and branches

Answer 29

- arises from left sinus of ascending aorta, just above aortic semilunar valve - Left Anterior Descending Artery: supplies anterior of right and left ventricles - Circumflex Artery: runs in coronary sulcus , gives off left marginal artery, supplies left atrium and left ventricle , anastomoses with right coronary artery

Question 30

Left Ventricle:

Answer 30

- at the back of heart - divided into ventricle proper and aortic vestibule (leads into the aorta) - contains two papillary muscles and their chordae tendinae - thicker wall, longer, narrower, stronger than right ventricle

Question 31

Right Ventricles:

Answer 31

-Papillary muscles: attached to chordae tendinae, contract to tighten chordae tendinae, preventing cusps of tricuspid valve being everted, preventing blood from leaking from ventrivle into right atrium

Question 32

Left Atrium:

Answer 32

- smaller with thicker walls than right atrium, mostly smooth walls - receives oxygenated blood through four pulmonary veins

Question 33

Right Atrium:

Answer 33

: Smooth walled sinus venarum, rough walled atrium proper: two vena cavae open into them - larger than left atrium - right atrial pressure is higher than left atrial pressure

Question 34

-Right Auricle:

Answer 34

muscular pouch about right atrium

Question 35

-Fossa Ovalis:

Answer 35

blood runs from right atrium into left atrium through this

Question 36

-Pectinate muscles:

Answer 36

ridges of myocardium that are located in the atrium

Question 37

-Crista Terminalis:

Answer 37

junction between sinus venarum and right atrium proper