Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

VET 408: Cardio/Respiratory > Cardiac Dysrhythmias > Flashcards

Cardiac Dysrhythmias Flashcards

(84 cards)

Start Studying
1
Q

normal ECG (lead II) in dogs

A

P followed by QRS
- stable, unchanging PQ interval
- positive P wave
- net positive, narrow QRS
- positive or negative T wave that does not change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

normal ECG in horses (base-apex lead)

A

P followed by QRS
- stable, unchanging PQ interval
- M shaped, biphasic P wave
- net negative, narrow QRS
- positive or negative T wave that does not change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

normal sinus rhythm

A

NSR; regular rhythm initiated by the sinus node, conducted normally, and normal rate for the species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

sinus bradycardia

A

lower than normal rate

rest is the same as NSR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

sinus tachycardia

A

higher than normal rate

rest is the same as NSR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

sinus arrhythmia

A

regularly irregular

rate increases and decreases at regular/predictable intervals

respiratory sinus arrhythmia: normal in dogs; increases HR on inspiration, decreases HR on expiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

supraventricular

A

originating from the upper chambers (atria)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

junctional

A

originating from the atrioventricular junction (around AV node)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

ventricular

A

originating from the lower chambers (ventricles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is ECG not sensitive for detecting

A

heart failure/disease resulting in dysfunction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is paper speed used to measure

A
  1. heart rate
  2. complex/interval duration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

standard paper speeds and corresponding values

A

25 mm/s: small box is equal to 0.04 seconds

50 mm/s: small box is equal to 0.02 seconds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what does a faster or slower paper speed correlate to

A

faster paper speed = widens complexes (stretches out X axis)

slower paper speed = narrows complexes (squishes in X axis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

do you use a faster or slower paper speed in cats

A

faster

allows better visualization of complexes due to fast HR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is calibration used to measure

A

complex size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

standard complex sizes

A

10 mm/mV: small box = 0.1 mV

20 mm/mv: small box = 0,05 mV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what causes artifact on ECG

A

poor electrode contact
shivering
purring
electrical interference
respiratory motion
reversed leads
limb movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

do artifacts disrupt the underlying rhythm

A

NO - should still have underlying rhythm

QRS complexes always followed by T wave

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what does the P wave correspond to and how does it look on ECG

A

atrial depolarization

SA: small, rounded, positive

LA: M shaped/biphasic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what does the PQ interval correspond to

A

conduction through the slow AV node; includes depolarization of atria and specialized conduction system

should NOT vary between beats

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what does the QRS complex correspond to

A

ventricular depolarization

should be NARROW

SA: negative Q, positive R, negative S

LA: negative QRS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what does the T wave correspond to

A

ventricular repolarization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

J point

A

end of the R or S wave (if S is present)

starting point of the ST interval

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

ST segment

A

isoelectric line - no current should be flowing

should be at the same level as the TP interval

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
TP interval
isoelectric line does not change polarization
26
what is ST depression
when the ST segment is below (more negative) than the TP interval
27
what is ST elevation
when the ST segment is above (more positive) than the TP interval
28
what does the QT interval correspond to
ventricular depolarization + repolarization slow HR= longer QT interval
29
what is the risk of prolonged QT interval
increased risk of premature depolarizations leading to ventricular fibrillations
30
mean electrical axis
average vector of depolarization sum of all electrical activity during ventricular depolarization depends on origin of AP, size of ventricles, speed of electrical conduction
31
what is the normal QRS MEA in dogs
left caudal most positive leads are lead II and aVF
32
what is the normal QRS MEA in cats
left and right caudal most positive leads are leads II, III, and aVF
33
p mitrale
wide P wave caused by LEFT atrial enlargement (takes longer for depolarization to occur
34
p pulmonale
tall P wave caused by RIGHT atrial enlargement (amplifies depolarization)
35
what causes abnormal P wave morphology
non-SA node, supraventricular generated AP (atrial escape beats) negative P wave
36
what causes unrelated P waves
random P waves not associated with QRS complex caused by miscommunication between atria and ventricles (AV block w/ ventricular escape)
37
what causes absent P waves
1. failure of SA or other nodes to depolarize 2. ectopic/normal P waves are hiding in the preceding complex 3. SA node usurped by abnormal rhythm (atrial fibrillation, flutter, ventricular tachycardia)
38
what causes an abnormal PQ interval
miscommunication between atrium and ventricle (AV block, ventricular tachycardia)
39
what does a tall QRS complex mean
left ventricular enlargement NORMAL MEA - direction is normal but depolarization is strong (concentric or eccentric hypertrophy)
40
what does a wide QRS complex mean
abnormal ventricular depolarization or conduction (ventricular ectopy, ventricular premature complexes, ventricular escape rhythm, bundle branch block)
41
where does sinus rhythm originate from
SA node
42
where does atrial escape beats originate from
atrium but non SA node
43
where does junctional escape beats originate from
atrioventricular junction
44
where does a L sided ventricular premature complex (VPC) originate from
left ventricle (negative QRS)
45
where does a R sided VPC originate from
right ventricle (positive QRS)
46
what does an overly narrow QRS complex mean
supraventricular origin of AP
47
what are the steps of evaluating cardiac rhythm
1. heart rate 2. sinus rhythm, yes or no? 3. ID arrhythmias and conduction abnormalities
48
bradyarrhythmia
slow HR that is not initiated by SA node
49
tachyarrhythmia
fast HR that is not initiated by SA node
50
how to calculate HR at 25 mm/s paper speed
count the number of beats in 30 big boxes 30 big boxes = 6 seconds 10 x # beats = # of beats per minute
51
how to calculate HR at 50 mm/s paper speed
count the number of beats in 30 big boxes 30 big boxes = 3 seconds 20 x # beats = # beats per minute
52
how to measure instantaneous heart rate
count the number of big boxes between the R-R interval 25 mm/s: 300 / # of big boxes between R-R interval 50 mm/s: 600 / # of big boxes between R-R interval
53
how to evaluate if there is sinus rhythm
1. are there p waves? 2. are the p waves associated with QRS? 3. is the p wave MEA normal? 4. if the rate is variable - does it behave like sinus rhythm (gradually increase/decrease)? 5. look for respiratory sinus arrhythmia (dogs; wandering pacemaker)
54
wandering pacemaker
change in P wave height within one reading caused by change in ANS tone variable ANS innervation --> rate and location of SA node discharge changes
55
respiratory sinus arrhythmia: inspiration
vagal tone predominates --> slows HR, moves SA discharge apically
56
respiratory sinus arrhythmia: expiration
vagal tone decreases --> increases HR --> moves SA discharge back to SA node
57
regularly irregular rhythm
changes in rhythm occurs at regular intervals can be NORMAL (dogs - respiratory sinus arrhythmia) can be ABNORMAL (complete AV block with ventricular escape OR supra-ventricular tachycardia)
58
irregularly irregular rhythm
changes in rhythm are patternless/chaotic always abnormal (ex. atrial fibrillation, ventricular tachycardia)
59
premature complexes
early depolarizations, can be ventricular or atrial in orign
60
ventricular premature complexes (VPCs)
sinus rhythm followed by a ventricular depolarization
61
bigeminy
normal beat followed by abnormal beat can be ventricular or atrial
62
atrial premature complexes (APCs)
sinus rhythm with early atrial depolarizations (supra ventricular) P waves are hidden in the preceding QRS because the atrium depolarizes too early
63
examples of QRS without a P wave
sinus arrest atrial standstill atrial fibrillation ventricular tachycardia atrial premature complexes
64
sinus arrest
SA node fails, causing a period of arrest (isoelectric line) before a non-SA node takes over and slowly spontaneously generates an AP (junctional escape beat)
65
atrial standstill
atrial muscle dysfunction causing complete lack of atrial depolarization (no P wave)
66
atrial fibrillation
SA node is being usurped by an ectopic rhythm causes "jiggling baseline" from small fibrillary waves no p wave, highly variable R-R interval
67
ventricular tachycardia
SA node is still firing and atrium is still contracting, but ventricle is driven by ectopic focus alternates from sinus to arrhythmia and back
68
AV block
disruption in the communication between the atria and ventricles caused by increased vagal tone (AV node disease, drugs, athletic dogs)
69
1st degree AV block
prolongation/delay of PQ interval
70
2nd degree (type I) AV block
PROGRESSIVE delay of PQ interval until non-conducted P wave normal sinus rhythm followed by a P without a QRS can be benign (calm horses at rest)
71
2nd degree (type II) AV block
PQ interval is normal up until the non-conducted P wave (NO progressive delay of PQ interval) NOT benign - caused by conduction system disease
72
low grade 2nd degree type II AV block
one non-conducted P wave at a time (2:1 AV conduction)
73
high grade 2nd degree type II AV block
>1 non-conducted P wave at a time (>3:1 AV conduction)
74
3rd degree AV block
complete dissociation of atria and ventricles; no conduction across AV node occurs bundle of his/purkinje have to take over conduction of ventricles (bradyarrhythmia) BUT SA node is still firing at its own pace causes 2 independent pacemakers to be firing
75
right axis deviation
MEA deviates to right cranial or right caudal caused by: right ventricular enlargement or right bundle branch block
76
right ventricular enlargement
MEA becomes right and caudal with NARROW QRS negative lead I net positive aVF narrow QRS ex. pulmonary stenosis
77
right bundle branch block
MEA becomes right and caudal with WIDE QRS delayed conduction though R bundle branch leading to slow depolarization of RV
78
what causes a wide QRS complex
QRS takes longer than normal: ventricular: VPC or ventricular escape (most wide complexes) SA/supraventricular: atrial fibrillation, junctional escape beats, bundle branch block
79
left bundle branch block
normal MEA (left caudal) with wide R wave in lead II
80
left axis deviation
MEA deviates to left cranial (not caudal bc that is normal) caused by L anterior fascicular block
81
L anterior fascicular block
delayed conduction through anterior fascicle of left bundle branch common in CATS only due to concentric left ventricular hypertrophy causes positive lead I, negative aVF
82
what causes arrhythmias (in general)
disorders of impulse formation OR disorders of impulse conduction OR both (most often)
83
paroxysmal
arrhythmias that last <30 seconds
84
sustained
arrhythmias that last >30 seconds

VET 408: Cardio/Respiratory (38 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions