ECG Abnormalities

Question 1

what is a supraventricular rhythm?

Answer 1

one that originates above the AV node, whether conducted through it or not

Question 2

what is characteristic of a supraventricular rhythm?

Answer 2

narrow QRS complex (<3 small squares)

Question 3

characteristics on ECG of sinus rhythm?

Answer 3

P wave followed by a QRS
QRS followed by a P wave
PR interval <200ms

Question 4

what allows for contraction in sinus rhythm?

Answer 4

SA node depolarises, causing atria to contract
delay to conduct to AV node (PR interval)
ventricles contract

Question 5

characteristics of ECG in sinus arrhythmia?

Answer 5

P wave followed by a QRS
QRS followed by a P wave
PR interval <200ms
irregular rhythm

Question 6

what can cause sinus arrhythmia?

Answer 6

respiration

Question 7

characteristics on ECG of AFib?

Answer 7

irregularly irregular QRS complexes
no P waves
ragged baseline

Question 8

what happens to the conduction in AFib?

Answer 8

disorganised electrical activity

AV node receiving continuous impulses, conducting some of them

Question 9

difference between AFib and atrial flutter?

Answer 9

AFib is irregular atrial contraction

atrial flutter is regular, but faster than ventricles

Question 10

characteristics of ECG of atrial flutter?

Answer 10

regular QRS complexes
rate divisible into 300
f waves (saw tooth baseline)

Question 11

leads best to see saw tooth baseline?

what condition is this characteristic of?

Answer 11

V1 and lead II

atrial flutter

Question 12

what happens to cause a junctional rhythm?

Answer 12

origin of electrical impulse is the AV node as opposed to SA
atria and ventricles simultaneously receive the impulse

Question 13

characteristics of junctional rhythm ECG?

Answer 13

regular rhythm
normal QRS
no antegrade P wave, retrograde before ST segment and inverted

Question 14

what is a supraventricular tachycardia?

Answer 14

tachycardia that is generated involving th AV node or above

Question 15

ECG characteristics of a supraventricular tachycardia?

Answer 15

regular
tachycardia
narrow complex QRS
often no clear P waves

Question 16

ECG characteristics of a supraventricular ectopic?

Answer 16

regular
occurs on beats 3, 6, 9 etc..
P wave morphology differs

Question 17

what happens to cause a ventricular premature complex?

Answer 17

ventricles contract before they should

Question 18

what rhythm is assoc with haemodynamic compromise?

Answer 18

ventricular tachycardia

Question 19

ECG characteristics of ventricular tachycardia?

Answer 19

regular broad complex tachycardia

QRS >120ms

Question 20

what is ventricular fibrillation clinically associated with?

Answer 20

loss of consciousness

Hx of MI

Question 21

ECG changes of ventricular fibrillation?

Answer 21

irregular random baseline

no clear waveforms

Question 22

what can cause poor R wave progression?

Answer 22

LV failure

failure to remove bra

Question 23

what happens to cause heart block?

Answer 23

block in conduction between the atria and ventricles due to a problem with the AV node

Question 24

what can cause damage to the AV node?

Answer 24

ischaemia
drugs
age

Question 25

features of 1st degree heart block ECG?

Answer 25

fixed broad PR interval | stable length of PR interval

Question 26

Tx of 1st degree heart block?

Answer 26

none, can be normal

Question 27

ECG features of Mobitz type 1 heart block?

Answer 27

elongation of PR interval then a dropped beat

Question 28

Tx of Mobitz type 1 heart block?

Answer 28

may be normal in young, investigate in elderly

Question 29

ECG features of Mobitz type 2 heart block?

Answer 29

constant PR interval | every other P wave has no QRS

Question 30

which 2nd degree heart block is abnormal?

Answer 30

Mobitz type 2

Question 31

ECG features of third degree heart block?

Answer 31

no relationship between P and QRS | ventricular escape rhythm

Question 32

what is an escaped beat?

Answer 32

late beat from AV node

Question 33

what is an ectopic beat?

Answer 33

early beat

Question 34

what can cause pericarditis?

Answer 34

post MI viral bacterial

Question 35

ECG changes in an MI?

Answer 35

upward concave ST elevation PR depression widespread in >1 vascular territory

Question 36

what does non specific inter-ventricular conduction delay show on ECG?

Answer 36

broad QRS that does not exhibit LBBB/RBBB

Question 37

two types of VT?

Answer 37

monomorphic | polymorphic

Question 38

what happens in monomorphic VT?

Answer 38

scar is in ventricles from MI used for electrical impulse regular rhythm as always same length of travel

Question 39

another name for polymorphic VT?

Answer 39

torsades des pointes