Lecture 2: Electrocardiography Flashcards
1
Q
What position is best for ECG
A
right lateral
2
Q
where should electrodes be placed on patient
A
white: right arm
Black: left arm
Red: left leg
3
Q
What are bipolar leads
A
3 lead system, leads generate - to + pull between two electrodes
4
Q
what are the augmented unipolar leads
A
6 leads, mean output of two of three limb leads
5
Q
what are the leads used in augmented unipolar leads and where they placed
A
- AVL- left arm
- AVR- right arm
- AVF: left leg
6
Q
describe the generation of ECG
A
- Sinus discharge- early atrial activation
- Complete atrial activation (p wave)
- Early ventricular activation-septum (delay through AV node (R-Q)
- Middle ventricular activation apex (P-R)
- Complete ventricular activation- base (P-QRS)
- Ventricular repolarization ( t wave)
7
Q
What is paper speed
A
50mm/sec
8
Q
What is double sensitivity/ amplitude
A
20mm/mV
9
Q
what is full sensitivity/ amplitude
A
10mm/mV
10
Q
what is half sensitivity/amplitude
A
5mm/mV
11
Q
what interval on ECG do you measure for HR
A
number of single boxes between two R-R
12
Q
how do you calculate HR on 50mm paper speed
A
of boxes (0.02 sec) =X
60/X= HR
13
Q
what is the primary pacemaker of heart rate
A
SA node
14
Q
what is SA node HR
A
60-160bpm
15
Q
what is the HR if fired from the AV node
A
60-100bpm
16
Q
what is HR if fired from Purkinje fibers/ventricle in dogs and cats
A
dogs: 30-40bpm
Cats: 80-100bpm
17
Q
what is the HR
A
37 boxes (0.02 sec)=0.74 sec
60 secs/0.74 secs=81 bpm
18
Q
how would the P wave appear with left atrial enlargement
A
prolonged duration
19
Q
how would p wave appear with right atrial enlargement
A
increased amplitude
20
Q
PR interval= __
A
AV node conduction
21
Q
how would QRS complex appear with right ventricular enlargement
A
prolonged duration
22
Q
how would QRS complex appear with left ventricular enlargement
A
increase amplitude
23
Q
what circled/what wrong. What does this tell you about heart
A
VPC
QRS complex wider and taller—> right and left ventricular enlargement
24
Q
what can cause abnormalities in the T wave
A
electrolyte abnormalities (elevated)
25
define arrhythmia
absence of rhythm
26
define dysrhythmia
abnormal rhythm
27
what does it mean when something is supraventricular
originates above bifurcation of bundle of His
28
what does supraventricular tachycardia mean
atrial tachycardia
29
respiratory sinus arrhythmia indicates __
vagal tone
30
what occurs during respiratory sinus arrhythmia
increase HR during inspiration
31
what wrong
respiratory sinus arrhythmia (normal)
32
what influences wandering pacemaker on ECG
vagal tone
33
what occurs in wandering pacemaker on ECG
P-wave changes in height- taller during faster rates
34
What wrong
wandering pacemaker- P waves taller during faster HR
35
sinus bradycardia is enhanced by __tone
parasympathetic
36
what wrong and what tx
sinus bradycardia
Tx: atropine
37
sinus tachycardia enhanced by __ tone
sympathetic
38
what are some causes of sinus tachycardia
pain, hypovolemia, fear, hyperthyroidism
39
what wrong
sinus tachycardia
40
what is right bundle branch block
conduction delay or block of sinus impulse in the right bundle branch
41
right bundle branch block may indicate __ or __
pulmonary hypertension or pulmonary stenosis
42
how does the P-QRS complex appear in right bundle branch block
P waves- normal
PR- sinus
QRS- prolonged
S waves deep
43
what wrong
right bundle branch block- prolonged QRS
44
what is left bundle branch block
conduction delay or block of sinus impulses in left bundle branch
45
left bundle branch block may indicate __ or __
DCM or DVD
46
what is appearance of left bundle branch block P-QRS
P waves- normal
PR- sinus
QRS- prolonged (but correct direction vs right), noticed QRS complex
47
what wrong
left bundle branch block
48
what are some sinoatrial nodal diseases that cause bradyarrythmias
1. Sinus bradycardia
2. Sick sinus syndrome
3. Atrial standstill
49
what breed commonly gets sinus sick syndrome
miniature schnauzer
50
what wrong and what tx
sick sinus syndrome
Tx: pacemaker
51
what is atrial standstill
Sinus node arrest
52
what are some causes of atrial standstill
hyperkalemia, atrial myopathy, artifact
53
What wrong
atrial standstill
54
what is AV block
AV node separates conduction from the atrial from the ventricle
55
AV node disease typically due to __ or __
fibrosis or infection
56
what occurs in first degree AV block
prolonged PR and no dropped beats
57
what is second degree AV block mobitz type 1
PR interval prolongs, then drop beat
58
what is second degree AV block mobitz type II
PR interval constant then drop beat
59
what is high grade second degree AV block
normal P-QRS then multiple P waves in a row
60
what is the cause of high grade second and 3rd degree AV block
fibrosis or endocarditis
61
what is 3rd degree AV block
complete atrial and ventricular separation with escape beats
62
what wrong and what tx
High grade second degree
AV block
Tx: pacemaker
63
what wrong and what tx
1st degree AV block
No tx
64
what wrong and what tx
2nd degree AV block mobitz type 1
Tx: atropine challenge
65
what wrong and what tx
3rd degree AV block
Tx: pacemaker
66
what wrong and what tx
second degree AV block mobitz type 2
Tx atropine challenge
67
what is the origin for narrow QRS complexes
supraventricular
68
what is origin for wide QRS complexes
ventricular origin
69
what wrong and what origin for each
top: narrow QRS, supraventricular origin
Bottom: wide QRS, ventricular origin
70
what wrong
atrial premature contraction
71
narrow QRS tachycardia= __tachycardia
supraventricular
72
what are some regular rhythms for narrow QRS tachycardia
1. Sinus tachycardia
2. Ectopic atrial tachycardia
3. Re-entry
73
what are some irregular rhythms for narrow QRS tachycardia
1. A-fib
2. A-flutter
74
what wrong
atrial tachycardia- abnormal p wave precedes QRS, often buried in preceding T wave
75
do accessory pathways cause tachycardia or bradycardia
tachycardia >300bpm
76
what is atrial fibrillation
no p waves, irregular rhythms
77
what is pathologic causes for A-fib
1. Left atrial enlargement
78
what wrong
A-fib (no p waves)
79
what cause atrial flutter
re-entry circuit in atrium
80
what wrong
atrial flutter
81
what occurs during VPC
premature QRST, prolonged QRS
82
what wrong
VPC
83
what is a compensatory pause in VPC
takes 2 normal R-R intervals to occur after VPC before return to normal beat
84
what is a non-compensatory pause in VPC
return to regular beat after VPC before two R-R intervals
85
which is compensatory pause vs non-compensatory pause
top: compensatory
Bottom: non-compensatory
86
Based on the positive direction of VPC what side of heart did this occur on
right
87
based on the negative direction of VPC what side of heart did this occur on
left
88
what does bigeminy mean in VPC
sinus-VPC-sinus-VPC-sinus
89
what does trigeminy mean in VPC
VPC-sinus-sinus-VPC-sinus-sinus
90
what are the cardiac causes of VPC
1. Cardiomyopathy
2. DVD
3. Endocarditis
91
what are some extra-cardiac causes of VPCs
pain, anemia, sepsis, splenic, hypovolemia, UTI
92
what is accelerated idioventricular rhythm
AV dissociation, 3 or greater VPCs in a row with HR between 70-160bpm
93
what wrong
accelerated idioventricular rhythm
94
what are the arrows pointing at
fusion beats, fusion of sinus beat with PVC
95
what is ventricular tachycardia
complete AV dissociation, wide QRS, HR >160bpm
96
what wrong
V-tach
97
what are the cardiac causes of ventricular tachycardia
cardiomyopathy
98
what are the extracardiac causes of V-tach
electrolyte imbalance, neoplasia, sepsis
99
t or f: patients in v-tach are hemodynamically stable
false
100
what is tx for v-tach
goal: conversion
1st: lidocaine 2mg/kg IV
2nd: procainamide: 5mg/kg IV
3rd: sotalol (if normal Lv function)
101
what wrong
V-fib
102
what do you do to tx v-fib
1. CPR
2. Electrical defibrillation
3. Percordial thump
4. Electrolyte replacement (potassium, calcium)
