ECG

Question 1

What leads show a lateral MI and which artery?

Answer 1

V4,5,6. 1 and aVL.

Circumflex artery

Shows inferior ST depression.

Question 2

What leads show a anterior/septal MI and which artery?

Answer 2

V1,2,3.

Left anterior descending

Question 3

What leads show an inferior MI and which artery?

Answer 3

II, III, aVF.

Right coronary artery.

Question 4

What is seen in posterior STEMI?

Answer 4

Reciprocal changes e.g. anterior ST depression

Question 5

What is the normal PR interval?

Answer 5

120-200ms.

Question 6

What is normal QRS complex?

Answer 6

<120 ms.

Question 7

What is normal QT interval?

Answer 7

340-440ms.

Question 8

What is tachycardia?

Answer 8

Rate >100bpm. Narrow complex using normal conduction system e.g. sinus, atrial flutter. or
broad complex

Question 9

What is bradycardia?

Answer 9

Rate <60bpm

Question 10

What are causes of broad complex tachycardia?

Answer 10

Usually ventricular in origin. When normal conduction system is changed

Question 11

What are the different types of heart block?

Answer 11

Disrupted passage of electrical impulses through the AV node

1. Ist degree = prolonged PR interval
2. 2nd degree Mobitz 1 = prolonged PR interval until a QRS is dropped, then resets.
3. Mobitz 2 = regularly missed QRS
4. Complete = independent P and QRS. Common in inferior MI.

Question 12

What is seen in axis deviation on ECG?

Answer 12

Left : aVLK more positive

Right: aVF and lead III more positive. p