Exam 1: Cardiac Electrophysiology Paper Questions

Question 1

what is a cardiac pacemaker

Answer 1

generates an action potential to initiate a heart beat

Question 2

hypoxia

Answer 2

lack of oxygen in the tissue

Question 3

ischemia

Answer 3

lack of blood supply

Question 4

how could ischemia effect functioning of the heart

Answer 4

if there is an insufficient blood supply, there will not be enough blood for the heart to pump and it will over work to pump blood

risk for a heat attack

Question 5

arrhythmia

Answer 5

irregular heart rate

Question 6

2 predominant pacemakers

Answer 6

SA

AV

Question 7

where is the SA node located

Answer 7

in the groove between the RA and the superior vena cava

Question 8

what is the difference between pacemaker cells and force-producing myocytes

Answer 8

pacemaker cells: produce action potential to generate a heart beat
force: regulate the force that is needed to pump the blood to the body

Question 9

what is a resting membrane potential

Answer 9

static membrane potential ratio of ions inside and outside the cell when nothing is moving

Question 10

what is the cardiac pacemaker potential

Answer 10

depolarization

Question 11

bradycardia

Answer 11

decreased heart rate, lower than normal

Question 12

tachycardia

Answer 12

increased heart rate, higher than normal

Question 13

what is a muscarinic receptor

Answer 13

acetylcholine receptors (GPCR)

Question 14

what might an inward K+ current alone do to a cell’s membrane potential?

Answer 14

dec in cAMP , dec in Ca channels opening, dec slope of prepotential

hyperpolarize

Question 15

adrenoreceptor

Answer 15

receptive to epinephrine and norepinephrine

Question 16

systolic

Answer 16

top number, force your heart exerts each time it beats

Question 17

diastolic

Answer 17

bottom number

pressure in arteries when heart rests between beats

Question 18

pericardium

Answer 18

membrane surrounding heart

protects heart, holds it in place

Question 19

first degree heart block

what does it look like on ECG

Answer 19

electrical impulse still reaches ventricles, but slower than normal through AV node
may look like longer period f time between the P wave and QRS wave

Question 20

second degree heart block

what does it look like on ECG

Answer 20

signals between atria and ventricles delay or fail to conduct

PR interval longer or normal but stays constant whichever it is

Question 21

ventricular septal defect

how does it effect cardiac output

Answer 21

hole in heart abnormal connection between ventricles

blood gets pumped to the lungs - fluid in lungs heart working harder to pump

Question 22

cardiogenic shock

Answer 22

heart suddenly cannot pump enough blood to meet body/s needs