ECG

Question 1

What is the normal PR interval?

Answer 1

120-200ms (3-5 squares)

Question 2

What is a normal QRS width?

Answer 2

<120ms (3 squares)

Question 3

What conditions can present with a broad QRS complex?

Answer 3

Left and right bundle branch block
Paced rhythm
Ventricular tachycardia
Hyperkalemia
Hyper- or hypo-magnesemia
Sodium channel blockade
Atrial fibrillation with Wolff-Parkinson-White syndrome

Question 4

What can constitute a pathological Q wave?

Answer 4

> 40 ms (1 mm) wide
2 mm deep
25% of depth of QRS complex
Seen in leads V1-3

Question 5

What are hyperacute T waves?

Answer 5

Broad, asymmetrically peaked T waves
Present in the early stages of a STEMI (often precede ST elevation and Q waves)

Question 6

What is a ‘shark fin’ on an ECG?

Answer 6

Blurring of the QRS and T wave
Sign of profound ST-Deviation (e.g massive stemi)

Question 7

How can a LBBB present?

Answer 7

Broad QRS (>3 small square/0.12sec) and
Deep S wave in V1 and
No Q wave in V5/V6

Question 8

What does T wave inversion often indicate?

Answer 8

Ischaemia

Question 9

What do pathological Q waves often indicate?

Answer 9

Current or prior MI

Question 10

What is a normal axis?

Answer 10

-30 to 90 degrees

Question 11

What is considered significant ST elevation?

Answer 11

2mm in men
1.5mm in women

(Higher thresholds in younger people)

Question 12

What are delta waves characteristic of?

Answer 12

Wolf Parkinson White Syndrome