Test 1: lecture 7 ekg part 3

Question 1

4 questions to ask about an EKG

Answer 1

1. Is the rate fast or slow
2. Is the rhythm regular or irregular?
3. Is there a P wave for every QRS complex?
   Is there a P wave in front of every QRS complex?
   is there a QRS complex following every P wave?
4. Are the QRS complexes:
   – Supraventricular
   – Ventricular

Question 2

NSR for dog

Answer 2

70-170 bpm

Question 3

NSR for cats

Answer 3

120-240 bpm

Question 4

what are some things that cause tachycardia

Answer 4

increased sympathetic tone
fever, anemia, heart failure, adrenergic medications, and anxiety

Question 5

what are some things that cause sinus bradycardia

Answer 5

excessive vagal tone
sinus node pathology

Question 6

what is respiratory sinus arrhythmia

Answer 6

increased HR during inhale
decreased HR during exhale

reguarly irregular

common in dogs- caused by increased vagal tone

goes way with exercise, atropine or high sympathetic tone (stress, HF)

Question 7

what is an example of irregularly irregular

Answer 7

Afib

Question 8

Answer 8

sinus arrest
inappropriately long PP interval

long pause can cause fainting

can diagnose with holter monitor

Question 9

what kind of dogs get sick sinus syndrome

Answer 9

long pause cause fainting

schnauzers

Question 10

symptoms of sinus arrest in cats

Answer 10

fainting or seizures

long pause in beats

Question 11

what is an ectopic beat

Answer 11

beat that is started at somewhere other then sinus node

(something is wrong)

QRS without a P wave

Question 12

the ventricle depolarize without atrial depolarization is a —

Answer 12

ectopy

QRS without a P wave

Question 13

Answer 13

ventricular ectopic beat

QRS wide and wierd

conduction is slow from cell to cell cause it has to move through muscle cells instead of normal pathway

Question 14

what will happen to QRS with a supraventricular ectopic beat

Answer 14

impulse starts above the ventricle: sinus node, atrium, AV node

P wave will look abnormal, but QRS normal cause it moves through normal pathway

Question 15

what is a APC

Answer 15

atrial premature beat
supraventricular origin

ectopic beat that is caused by something other then sinus node firing- causes early beat

QRS looks normal

space from normal to APC is called P-P’

P’ may not be seen if too early, hidden by T wave of earlier beat

Question 16

P-P’

Answer 16

space between P wave and Pwave of ectopic beat

if close together with normal QRS normally APC (atrial premature beat)

beat orginates above the ventricle

Question 17

Answer 17

APC
atrial premature beat
supraventricular origin

normal looking QRS

P-P’ very short

Question 18

Answer 18

A fib- undulating baseline

Absence of P waves

Supraventricular QRS-T morphology (narrow)

Irregularly irregular rhythm

Question 19

three hallmarks of Atrial Fibrillation

Answer 19

Absence of P waves

Supraventricular QRS-T morphology(narrow)

Irregularly irregular rhythm

undulating baseline

Question 20

Answer 20

ventricular premature contraction (VPC)

short R-R interval
QRS wide and bizarre
no P wave
T wave looks weird

can be from his-purkinje system or from random ventricular myocardial cell

Question 21

VPCs will cause

Answer 21

ventricular premature contraction (VPC)

short R-R interval
wide and bizarre QRS
no P wave

Question 22

R on T phenomenon

Answer 22

VPCs that happen right after each other leads to ventricles not contracting properly→ will quiver

ventricular triplet can lead to ventricular fibrillation

no diastolic interval

Question 23

Answer 23

normal followed by VPC

probably not causing issues

Question 24

Answer 24

R on T phenomenon

PVC
ventricular triplet can lead to ventricular fibrillation

Question 25

3 or more ventricular premature contractions in a row is called

Answer 25

ventricular tachycardia can lead to fainting or Vfib QRS wide and wierd QRS slurs into T wave P wave present,but no relationship to QRS- often can't see, hidden by QRS complex

Question 26

Answer 26

V tach 3 or more VPC in a row QRS wide and wierd QRS slurs into T wave P present but hidden by QRS can lead to fainting, if R on T can lead to Vfib

Question 27

escape vs premature ectopic ventricular beat

Answer 27

**premature**: happens before normal R-R interval **escape**: long cause then wierd QRS, ventriculars sense no atrial beat and secondary pacemakers will depolarize spontaneously

Question 28

HR controlled by AV node will be

Answer 28

40-60 bpm

Question 29

HR controlled by purkinje cells would be

Answer 29

20-40 bpm

Question 30

Answer 30

escape beat beat caused by ventricle when there is no signal from atrium to beat causes wierd wide QRS

Question 31

Answer 31

ventricular premature beat beat with **wide and wierd QRS** before normal R-R interval

Question 32

Answer 32

ventricular escape beat happens later, beat started by ventricle when no beat from atrium wierd and wide QRS

Question 33

Answer 33

PVC every 3rd beat premature ventricular contraction wierd and wide QRS

Question 34

Answer 34

PVCs moving into Vfib lethal rhythm

Question 35

Answer 35

1st degree AV block slowed conduction: long PR interval

Question 36

Answer 36

2nd degree AV block intermittent failure of conduction: sometimes no QRS complex following P wave **wenckebach**

Question 37

Answer 37

3rd degree AV block AV conduction is absent P-waves are never followed by a QRS complex ventricles depolarize from subsidiary pacemakers

Question 38

1st degree AV block

Answer 38

Slowed conduction: PR interval prolonged

Question 39

2nd degree AV block

Answer 39

Intermittent failure of conduction: sometimes no QRS complex following P-wave type 1 wenckebach

Question 40

3rd degree AV block

Answer 40

complete AV conduction is absent * P-waves are never followed by a QRS complex * ventricles depolarize from subsidiary pacemakers P waves just doing its own thing, no QRS after it QRS that do show up are caused by ventricules, will be wierd and wide, but are needed to beat ventricles= **do not stop with meds**

Question 41

what can causes arrhythmias

Answer 41

scar tissue(infracts/ischemia) Disturbance of ionic homeostasis in myocytes (high K) drugs, stress (adrenaline) genetic defects in ion channels – Genetic defects in gap junctions between cells allowing normal electrical conduction(boxers)

Question 42

when to treat a patient with abnormal EKG

Answer 42

Hemodynamic compromise due to arrhythmia → reduced cardiac output →clinical signs: fainting, exercise intoleracne, hypotension, hypothermic Patients at significant risk for sudden death → with underlying heat disease → dilated cardiomyopathy (doberman), subarotic stenosis, hypertropic cardiomyopathy(Cats)