Dubin Ecg

Front 1

resting state

Back 1

myocytes polarized, interior of cell NEGATIVEly charged

Front 2

depolarization

Back 2

myocytes become positive and contract

Front 3

repolarization

Back 3

myocyte interiors regain resting negative charge

Front 4

automaticity

Back 4

ability of the SA node to generate pacemaking stimuli

Front 5

AV node

Back 5

sole pathway to conduct depolarization stiumuls through the fibrous AV valves

Front 6

tRicuspid

Back 6

Right

Front 7

mitraL

Back 7

left

Front 8

P wave

Back 8

represents atrial contraction

Front 9

conduction through AV node and bundle of His

Back 9

depolarization conducts slowly through the AV node due to slow-moving Ca++ ions, then rapidly through the His bundle and L & R bundle branches due to fast-moving Na+ ions

Front 10

Q wave

Back 10

beginning of QRS, first downward reflection of the complex

Front 11

R wave

Back 11

first upward wave in the QRS complex

Front 12

S wave

Back 12

any downward wave that is PRECEDED by an upward wave

Front 13

QRS complex

Back 13

represents ventricular depolarization and contraction

Front 14

T wave

Back 14

represents ventricular repolarization

Front 15

ST segment

Back 15

horizontal segment following QRS, preceding T wave. Elevation or depression indicates pathology.

Front 16

QT interval

Back 16

represents duration of ventricular systole, from beginning of QRS to end of T wave

Front 17

release of free Ca++ cells

Back 17

produces contraction

Front 18

controlled outflow of K+ ions

Back 18

repolarization

Front 19

Na+ ions

Back 19

produce cell-to-cell conduction of depolarization

Front 20

EKG graph paper

Back 20

small boxes 1 mm, large 5 mm

Front 21

height & depth of waves measures

Back 21

voltage

Front 22

amplitude of wave

Back 22

magnitude (in mm) of upward or downward deflection

Front 23

positive deflections

Back 23

upward

Front 24

negative deflections

Back 24

downward

Front 25

time between two heavy black lines

Back 25

0.2 seconds

Front 26

time between two light black lines

Back 26

0.04 seconds

Front 27

4 small squares

Back 27

0.16 seconds

Front 28

lead I

Back 28

horizontal - left arm +, right arm -

Front 29

lead III

Back 29

diagonal -- left arm -, left leg +

Front 30

lead II

Back 30

diagonal -- right arm -, left leg +

Front 31

AVF lead

Back 31

left foot +, both arms -

Front 32

AVR

Back 32

right arm +, left leg/left arm -

Front 33

AVL

Back 33

left arm +, left leg, right arm -

Front 34

lateral leads

Back 34

I & AVL, both have positive electrode laterally on the left arm

Front 35

inferior leads

Back 35

II, III, & AVF -- all have positive electrode positioned on L foot

Front 36

chest leads

Back 36

V1-V6, always positive

Front 37

right chest leads

Back 37

V1, V2

Front 38

left chest leads

Back 38

V5, V6

Front 39

limb leads plane

Back 39

frontal

Front 40

chest leads plane

Back 40

horizontal

Front 41

sympathetic

Back 41

secretes norepinephrine; activates adrenergic receptors

Front 42

parasympathetic

Back 42

secretes acetylcholine; activates cholinergic receptors

Front 43

norepinephrine

Back 43

activate adrenergic receptors, cause SA node to pace faster. Improves AV node conduction and accelerates conduction through atrial and ventricular myocardium, increases contraction

Front 44

actetylcholine

Back 44

inhibits SA nodes, decreasing heart rate, decreases myocardial conduction and depresses AV node, diminishes contraction.

Front 45

vagus nerve

Back 45

body's main sympathetic pathway

Front 46

sympathetic stimulation of arteries

Back 46

causes constriction with alpha adrenergic receptors

Front 47

parasympathetic stimulation of arteries

Back 47

causes dilation with cholinergic receptors

Front 48

merciful syncope

Back 48

parasympathetic response slow SA node, dilates arteries, causes loss of consciousness

Front 49

vagal maneuvers

Back 49

stimulate parasympathetic reflex that inhibits SA node and AV node; carotid massage, induced gagging, bear down

Front 50

response to standing

Back 50

sympathetic response constricts peripheral arteries and prevents syncope

Front 51

orthostatic hypotension

Back 51

abrupt fall in BP caused by failure of compensatory sympathetic mechanisms

Front 52

neuro-cardiogenic syncope

Back 52

parasympathetic response to prolonged standing, causes vasodilation and slowing of pulse - syncope

Front 53

SA node

Back 53

heart pacemaker

Front 54

SA node location

Back 54

upper posterior wall of R atrium

Front 55

normal sinus rhythm

Back 55

60-100 bpm

Front 56

sinus bradycardia

Back 56

less than 60 BPM

Front 57

sinus tachycardia

Back 57

sinus rhythm with rate > 100 BPM

Front 58

automaticity foci

Back 58

potential pacemakers which assumes pacemaking when SA node fails. Atrial, AV junction, ventricular

Front 59

atrial rates

Back 59

60-80 BPM

Front 60

AV junction rates

Back 60

40-60 BPM

Front 61

ventricular rates

Back 61

20-40 BPM

Front 62

dominant pacemaker

Back 62

fastest functioning pacemaker will overdrive-suppress all slower pacemakers

Front 63

rate count numbers

Back 63

300, 150, 100, 75, 60, 50

Front 64

5 pieces to evaluate EKG

Back 64

rate, rhythm, axis, hypertrophy, infarction

Front 65

regular rhythm

Back 65

constant, unvarying rate

Front 66

bachmann's bundle

Back 66

originates in the SA node and distributes depolarization to the left bundle

Front 67

conduction pathways from the SA to the AV node

Back 67

Anterior, Middle and Posterior internodal tracts

Front 68

wandering pacemaker

Back 68

* P' wave shape varies;

* atrial rate less than 100;

* irregular ventricular rhythm.

Front 69

multifocal atrial tachycardia

Back 69

* P' wave shape varies;

* atrial rate exceeds 100;

* irregular ventricular rhythm.

Front 70

atrial fibrillation

Back 70

*irregular rhythm;

*continuous chaotic atrial spikes;

*irregular ventricular rhythm;

Front 71

escape rhythms/beats

Back 71

* atrial escape rhythm/beat;

* junctional escape rhythm/beat;

* ventricular escape rhythm/beat;

Front 72

atrial escape beat/rhythm

Back 72

sinus node arrest leads to single beat, or sustained atrial rhythm at 60-80 BPM

Front 73

junctional escape beat/rhythm

Back 73

sinus node arrest then atrial foci fail leads to junctional escape rhythm

Front 74

retrograde atrial depolarization

Back 74

pacing stimulus from the AV node also depolarizes atria from below, causes inverted P' wave

Front 75

ventricular escape rhythm

Back 75

Mechanism 1: AV block prevents stimulation by SA/atrial pacing.

Mechanism 2: total failure of SA node and all automaticity foci above the ventricles leads to full ventricular pacing

Front 76

atrial and junctional irritants (cause premature beats)

Back 76

* adrenaline;

* increased sympathetic stimulation;

* caffeine, amphetamines, cocaine, other bta-1 receptor stimulants;

* excess digitalis, some toxins, ETOH;

* hyperthyroidism;

* stretch;

Front 77

premature atrial beat

Back 77

resets SA node pacing

Front 78

premature atrial beat with aberrant ventricular conduction

Back 78

caused when one bundle branch has not repolarized completely, an causes slight delay in depolarization and widened QRS

Front 79

non-conducted premature atrial beat

Back 79

caused when AV node is not fully repolarized and still refractory to stimulus. P wave with no QRS-T response -- appearance of block.

Front 80

atrial bigeminy

Back 80

PAB at the end of every normal cycle

Front 81

atrial trigeminy

Back 81

PAB after two normal cycles

Front 82

widened QRS

Back 82

consider aberrant junctional or atrial beat

Front 83

ventricular focus irritability causes

Back 83

* low O2;

* Low K+;

* pathology -- mitral valve prolapse, stretch, myocarditis.

Front 84

most common cause of PVCs

Back 84

hypoxia

Front 85

parasystole

Back 85

PVCs coupled to a long series of normal cycles

Front 86

mitral valve prolapse/Barlow syndrome

Back 86

* 6-17% of females, 1.5% males;

* causes multi-focal PVCs;

*

Front 87

R on T phenomenon

Back 87

PVC falls on a T wave -- vulnerable period, likely to start a run of Vtach

Front 88

paroxysmal tachycardia

Back 88

150-250 BPM

Front 89

flutter tachyarrhythmia

Back 89

250-350 BPM

Front 90

fibrillation tachyarrhythmia

Back 90

350-450 BPM

Front 91

digitalis

Back 91

provokes atrial focus, and inhibits AV node -- possible block.

Front 92

reentry tachycardia

Back 92

continuous circuit around the AV node that rapidly paces the atria and ventricles

Front 93

supraventricular paroxysmal tachycardia

Back 93

paroxysmal atrial tachycardia and paroxysmal junctional tachycardia

Front 94

ventricular tachycardia =

Back 94

run of PVCs

Front 95

ventricular tachycardia indicates

Back 95

coronary insufficiency, poor oxygenation of the heart

Front 96

wide QRS complex SVT

Back 96

patient with coronary disease/infarction -- uncommon; QRS width < 0.14 sec; rare AV dissociation showing captures or fusions; raare extreme Right Axis Deviations

Front 97

Ventricular tachycardia

Back 97

very common in pt with coronary disease or infarction; QRS >0.14 sec; AV dissociations shows captures or fusions; Extreme Right Axis Deviation

Front 98

torsades de pointes

Back 98

two competitive irritable foci

Front 99

atrial flutter

Back 99

consecutive, identical flutter waves in rapid back-to-back succession. Sawtooth appearance.

Front 100

ventricular flutter

Back 100

smooth sine-wave pattern; arrhythmia rapidly deteriorates

Front 101

fibrillation

Back 101

rapid discharges from multiple foci

Front 102

bundle of Kent

Back 102

accessory pathway that causes ventricular pre-excitation in Wolff-Parkinson-White syndrome

Front 103

Lown-Ganong-Levine Syndrome

Back 103

AV node is bypassed by an extension of the anterior internodal tract. Without the conduction delay of the AV node. Rapid atrial rates are conducted directly to the Bundle of His.