ECG

Question 1

P wave

Answer 1

Atrial Depolarisation through intranodal tract (POSTIVE DEFLECTION)

Question 2

PR Interval

Answer 2

AVN conduction delay

Question 3

Q wave

Answer 3

AVN will generate AP towards bundle of His (has right + left bundle branches). Must depolarise the septum which is the role of the left bundle branch = NEGATIVE DEPOLARISATION

Question 4

R wave

Answer 4

Depolarisation of the apex of the ventricle. Left thicker = greater conduction therefore resultant = POSTIVE DEFLECTION

Question 5

S wave

Answer 5

Depolarisation base of ventricle = NEGATIVE DEFLECTION

Question 6

QRS complex

Answer 6

Vent depolarisation + atrial repolarisation

Question 7

S-T segment

Answer 7

Ventricles still depolarised = NO DEFLECTION
ISOVOLUMETRIC SYSTOLE/DIASTOLE

Question 8

T wave

Answer 8

Repolarisation of the myocardium = + -> - . Negative moving towards negative = POSITIVE DEFLECTION

Question 9

12 lead ECG

Answer 9

Right coronary artery = aVF, II, III (inferior)
Left anterior descending = V1-V4 (anterior + septal)
Left circumflex artery = V5, V6, aVL, I (lateral)

Question 10

Lead 2

Answer 10

NORMAL SINUS RHYTHM
- ON RIGHT ARM
+ ON LEFT LEG

Question 11

3 Types of leads

Answer 11

3 Bipolar leads (RA = - LL = +, LA = +/-)
3 Augmented leads
6 chest leads = Gives coronal view