Cardiac Cycle

Question 1

what ECG wave occurs when sodium influx into atrial myocytes is occurring?

Answer 1

P wave

Question 2

biggest wave on the ECG?

Answer 2

R wave

Question 3

definition of R wave?

Answer 3

positive going deflection

Question 4

definition of Q wave?

Answer 4

first negative going deflection

Question 5

are we concerned about absence of Q wave?

Answer 5

no; concerned if too big actually

Question 6

what begins at T wave?

Answer 6

ventricular repolarization

Question 7

what’s the definition of systole?

Answer 7

contraction of the heart; can be divided into atrial and ventricular

Question 8

how does the action potential spread from SA node to AV node?

Answer 8

gap junctions in the internodal pathway

Question 9

how does electrical potential of the heart reset?

Answer 9

first to depolarize is the first to repolarize

Question 10

definition of diastole?

Answer 10

relaxation of heart; usually only refer to ventricular

Question 11

what is blood pressure?

Answer 11

systole/diastole

Question 12

why is atrial pressure increasing during ventricular diastole?

Answer 12

blood is returning to the heart; valves closed

Question 13

what is the second heart sound associated with?

Answer 13

closing of the aortic and pulmonary valves

Question 14

what is the period in which no blood enters or leaves the ventricle while it is relaxing (AV and aortic valves closed)

Answer 14

isovolumetric relaxation

Question 15

what is the period during which blood rushes into ventricles?

Answer 15

diastasis

Question 16

what is 3rd heart sound?

Answer 16

diastasis; normally heard only in children (thin body wall)

Question 17

how is the rate of peripheral run off determined?

Answer 17

resistance to blood flow

Question 18

how is the a wave in the jugular pressure created?

Answer 18

atrial contraction

Question 19

how is c wave created?

Answer 19

isovolumetric contraction in ventricles (bulging of wall back into atria)

Question 20

how is v wave created?

Answer 20

pressure wave created as blood returns back to heart but can’t enter ventricle

Question 21

4th heart sound produced from?

Answer 21

atria contracting to squeeze more blood into ventricle (normally heard in kids); makes lub part sound funny

Question 22

when is a murmur heard?

Answer 22

blood is moving in a direction it shouldn’t be, blood is having a hard time moving in the direction it should be moving in

Question 23

systolic murmur causes?

Answer 23

blood moving back to atria (usually due to regurgitation); blood can’t get into aorta/pulmonary a. (stenosis)

Question 24

diastolic murmur causes?

Answer 24

blood moving back into aorta or pulmonary a. (regurgitation), blood can’t get into ventricle (stenosis)