A&P of CV System

Question 1

Apex of heart

Answer 1

Lowest part of the heart formed by inferolateral part of left ventricle
Projects anteriorly and to the left in level with the 5th intercostal space and left midclavicular line

Question 2

Base of heart

Answer 2

Upper border of heart involving left atrium, part of right atrium, and proximal portions of great vessel
Lies below second rib @ level of 2nd intercostal space

Question 3

Endorcardium

Answer 3

Endothelial tissue that lines interior of heart chambers and valves

Question 4

Epicardium

Answer 4

Serous layer of pericardium, contains epicardial coronary arteries and veins, autonomic nerves, and lymphatics

Question 5

Myocardium

Answer 5

Thick contractile middle layer of muscle cells that form bulk of heart wall

Question 6

Pericardium

Answer 6

Double walled connective tissue sac that surrounds the outside of the heart and great vessels

Question 7

Aorta

Answer 7

Largest artery in the body, begins at upper part of left ventricle then arches backward and to left to form arch of aorta, then descent within thorax and into abdominal cavity
Central pathway of blood from heart to rest of body

Question 8

Superior vena cava

Answer 8

Returns venous blood from head, arms, neck to right atrium

Question 9

Inferior vena cava

Answer 9

Returns venous blood from lower body and viscera to right atrium

Question 10

Pulmonary arteries

Answer 10

Arteries that carry deoxygenated blood from right ventricle to right and left lungs

Question 11

Pulmonary veins

Answer 11

Veins that carry oxygenated blood from the right and left lungs to left atrium

Question 12

Coronary arteries

Answer 12

Network of smaller vessels that carry oxygenated blood to myocardium
Right and left coronary arteries arise from ascending aorta

Question 13

Main branches of right coronary artery

Answer 13

Sinus node artery
Right marginal artery
Right posterior descending artery

Question 14

What is the main area supplied by the sinus node artery?

Answer 14

Right atrium

Question 15

What is the main area supplied by the right marginal artery?

Answer 15

Right ventricle

Question 16

What is the main area supplied by the right posterior descending artery?

Answer 16

Inferior walls of both ventricles and inferior portion of interventricular system

Question 17

Main branches of left coronary artery

Answer 17

Circumflex artery

Left anterior descending artery

Question 18

What is the main area supplied by the circumflex artery?

Answer 18

Left atrium
Posterior and lateral walls of left ventricle
Anterior and inferior walls of left ventricle

Question 19

What is the main area supplied by left anterior descending artery?

Answer 19

Anterior portion of interventricular system

Question 20

Where do right chambers pump blood?

Answer 20

Collect blood from body and pump it to lungs

Question 21

Where do left chambers pump blood?

Answer 21

Collect blood from body and pump to rest of body

Question 22

Direction of blood flow

Answer 22

Venous blood from SVC and IVC enters right atrium->pumped through tricuspid valve into right ventricle->right ventricle contracts to pump blood thru pulmonary valve into pulmonary trunk->blood picks up oxygenated releases CO in pulmonary capillaries->oxygenated blood returns via pulmonary veins to left atrium->blood flows thru bicuspid valve into left ventricle->blood then goes thru aortic valve into aorta

Question 23

Coronary veins

Answer 23

Includes coronary sinus, cardiac veins, and thesbian veins
Great cardiac, small and middle cardiac veins drain into coronary sinus, emptying into right atrium
Thesbian veins arise in myocardium and drain into all chambers of the heart, primarily right atrium and ventricle

Question 24

Components of cardiac conducting system

Answer 24

SA node, AV node, bundle of His, internal tracts, Purkinje fibers, right and left bundle branches

Question 25

What is the normal pacemaker of the heart?

Answer 25

SA node

Question 26

Sympathetic influence on cardiac conduction

Answer 26

Norepinephrine and epinephrine

Question 27

Parasympathetic influence on cardiac conduction

Answer 27

Acetylcholine released from vagus nerve

Question 28

Chronotropic effect

Answer 28

Affects heart rate, + effect= increased heart rate, - = decreased heart rate

Question 29

Inotropic effect

Answer 29

Affects force of heart contraction, += increase force of myocardial contraction, - = decrease force of myocardial contraction

Question 30

Baroreceptor reflex

Answer 30

Helps to maintain blood pressure thru baroreflex which includes arterial baroreceptors and cardiopulmonary receptors

Question 31

Arterial baroreceptors

Answer 31

High pressure receptors located in carotid sinus, aortic arch, and origin of right subclavian artery

Question 32

Cardiopulmonary receptors

Answer 32

Low pressure receptors

Question 33

How does sympathetic activation lead to increased blood pressure?

Answer 33

Leads to increased heart rate, increased cardiac contractility, venoconstricition, and arterial vasoconstriction There is an elevation in total peripheral resistance and cardiac output that also contributes

Question 34

Bainbridge reflex

Answer 34

Increase in venous return that stretches receptors in the wall of the right atrium which sends vagal afferent signals to CV center within medulla Ultimately, these signals inhibit parasympathetic activity resulting in increased HR

Question 35

Chemoreceptor reflex

Answer 35

Chemosensitive cells in the carotid bodies and aortic body responds to changes in pH status and blood oxygen tension

Question 36

When will chemoreceptors stimulate respiratory centers?

Answer 36

At an arterial partial oxygen pressure of less than 50 mmHg or in conditions of acidosis, will cause increase in depth and rate of ventilation

Question 37

Valsalva maneuver

Answer 37

Blood pressure and heart rate changes in response to increase in intrathoracic pressure Force expiration against a closed glottis produces increases intrathoracic pressure, increased central venous pressure, and decreased venous return Baroreceptors detect decrease in cardiac output and blood pressure resulting in increased HR and myocardial contractility via sympathetic activation

Question 38

Atrial systole

Answer 38

Contraction of right and left atria pushing blood into ventricles

Question 39

Atrial diastole

Answer 39

Period b/w atrial contractions when the atria are repolarizing

Question 40

Ventricular systole

Answer 40

Contraction of the right and left ventricles pushing blood into the pulmonary arteries and aorta

Question 41

Ventricular diastole

Answer 41

Period b/w ventricular contractions when ventricles are repolarizing

Question 42

Preload

Answer 42

Tension in ventricular wall at the end of diastole, reflects venous filling pressure that fills the left ventricle during diastole

Question 43

Afterload

Answer 43

Forces that impede the flow of blood out of the heart, primarily pressure in peripheral vasculature, compliance of aorta, and mass and viscosity of blood

Question 44

Stroke volume

Answer 44

Volume of blood ejected by each contraction of left ventricle Normal range is from 60-80 ml depending on age, sex, and activity

Question 45

Cardiac output

Answer 45

Amount of blood pumped from the left or right ventricle per minute, SV x HR CO for adult male at rest is 4.5-5.0 L/min, women produce slightly less CO can increase to 25 L/min during exercise

Question 46

Venous return

Answer 46

Amount of blood that returns to the right atrium each minute, similar in volume to CO CV system is a closed loop so venous return must equal CO when averaged over time