ECG Interpretation

Question 1

What does the ST segment represent?

Answer 1

The period between ventricular depolarisation (QRS) and ventricular repolarisation (T)

Question 2

ST elevation represents?

Answer 2

Myocardial Infarction

Question 3

ST depression represents?

Answer 3

Ischemia

Question 4

What is the process of ST depression during an ECG exercise test?

Answer 4

Upsloping ST > Horizontal ST > Downsloping ST

Question 5

What is the J point and what does it mean if it is 1mm below or above the Q wave?

Answer 5

Start of ST segment, below means ST depression, above means ST elevation

Question 6

True or False, ST elevation means a partial block

Answer 6

False! It’s a complete blockage and indicates MI

Question 7

What are some causes of ST elevation?

Answer 7

LV hypertrophy, pericarditis, ventricular fibrosis

Question 8

What substance is released and can be found in blood tests after a myocardial infarction?

Answer 8

Troponin

Question 9

True or False, STEMI is more severe than NSTEMI

Answer 9

True! NSTEMI is still a myocardial infarction, however it may only indicate a partial block

Question 10

List the STEMI evolution

Answer 10

First few minutes = complete block, ST elevation (or NSTEMI)
Hours to days = Q wave becomes deeper, T wave inverted, ST elevation
1 week = Slight ST elevation, T wave slightly inverted
Months = ST slightly higher than Q wave, rest of ECG normal

Question 11

What leads are Bipolar?

Answer 11

Lead I, II, III

Question 12

What leads are Unipolar?

Answer 12

Lead avR, avL, avF

Question 13

What leads are Precordial?

Answer 13

V1-V6

Question 14

What is Sinus Bradycardia?

Answer 14

Regular rhythm, <60bpm, normal P wave, normal QRS

Question 15

What is Sinus Tachycardia?

Answer 15

Regular rhythm, 100-160bpm, normal P wave, normal QRS

Question 16

What is sinus Arrhythmia?

Answer 16

Irregular rhythm, >60bpm, normal P wave, normal QRS

Question 17

What does it mean if there is no P wave?

Answer 17

Not a sinus rhythm and the contraction is not coming from the SA node

Question 18

What is the difference between Atrial flutter and Atrial fibrillation?

Answer 18

Atrial flutter is 3 depolarisations of the atria before QRS, Atrial fibrillation is rapidly depolarisation of the atria before QRS.

Question 19

What is Premature Ventricular Contraction?

Answer 19

Irregular rhythm, >60bpm, normal P wave, normal QRS - random ventricular depolarisation

Question 20

What is Atrial Fibrillation?

Answer 20

Irregular rhythm, rate may be fast or slow, p wave is absent, QRS is normal

Question 21

What is a Sinus Block?

Answer 21

Rhythm in atria and ventricle is regular when present, there is a pause between P wave

Question 22

What is a unifocal PVC?

Answer 22

PVC that look the same

Question 23

What is a multifocal PVC?

Answer 23

PVC that have different shapes

Question 24

What is R on T syndrome?

Answer 24

Very premature ventricular depolarisation

Question 25

What is Ventricular Tachycardia?

Answer 25

No p wave, regular rhythm, >100bpm, QRS is wide and bizzare, anything more than ventricular triplet
-Electrical current gets stuck in necrotic tissue

Question 26

What is Ventricular Fibrillation?

Answer 26

Ventricles are vibrating and firing from all over the place, rhythm is chaotic, rate is undeterminable, QRS is unidentifiable