Introduction to the ECG Flashcards
1
Q
Where should ECG leads be placed?
A
- V1 in the 4th intercostal space on the patient’s right-hand side of the sternum and V6 in the midaxillary line with V2, 3, 4 and 5 in between
2
Q
How should an ECG be read?
A
- Check date, time and patient
- Check paper speed (25mm/s) and gain (10mV/mm)
- Identify P/QRS/T
- Measure rate
- Check intervals (PR <1 large, QRS <3 small, QT < 11 small)
- Prolonged QTc
- >440 in men
- >460 in women
- >500 associated ventricular arrhythmias
- Prolonged QTc
- Determine the axis (normal +ve in I and II)
- Check P/QRS/T morphology
3
Q
What rhythm is this?
A
- Sinus bradycardia
- Rate <60
- Regular, narrow QRS
- P waves present
- P:QRS is 1:1
4
Q
What rhythm is this?
A
- Junctional bradycardia
- QRS is narrow so must be using specialised conduction system
- No P waves so no atrial depolarisation
- Impulse must be coming from the AV node
- Rate <60bpm
- Regular narrow QRS
- No P waves present
5
Q
What rhythm is this?
A
- Second degree AV block (Mobitz type I)
- Failure of AV nodal conduction
- Slowest rate <60bpm
- Irregular, narrow QRS
- P:QRS not 1:1 (increasing PR interval then dropped beat)
6
Q
What rhythm is this?
A
- Second degree AV block (Mobitz type II)
- AV node working normally or completely fails
- Slowest rate <60bpm
- Irregular, narrow QRS
- P:QRS not 1:1 (constant PR interval with intermittent dropped beats)
7
Q
What rhythm is this?
A
- Complete AV block
- No signal so cells in heart develop their own signals
- Rate <60bpm
- Regular broad QRS
- No relation between P and QRS
8
Q
What rhythm is this?
A
- Atrial fibrillation
- Cells depolarising in a chaotic fashion as they have lost control at SA node
- Rate is fast and variable
- Irregular, narrow QRS
- No P waves
9
Q
What rhythm is this?
A
- Sinus tachycardia
- Rate >100bpm
- Regular, narrow QRS
- P waves present
- P:QRS is 1:1
10
Q
What rhythm is this?
A
- Supraventricular tachycardia
- Rate usually >150bpm
- Regular, narrow QRS
- P waves present?
- P:QRS is 1:1
11
Q
What rhythm is this?
A
- Ventricular tachycardia
- Rate >120bpm
- Regular broad QRS
- P waves variable
12
Q
What condition is this?
A
- Posterior STEMI
- Tall R wave, tall upright T wave in leads V1-3
13
Q
What condition is this?
A
- Anterior STEMI
- ST elevation in anterior leads V1-6 and aVL
- Reciprocal ST depression in the inferior leads
14
Q
What condition is this?
A
- Inferior STEMI
- ST elevation in inferior leads II, III and aVF
- Reciprocal ST depression in the anterior leads
15
Q
What condition is this?
A
- Lateral STEMI
- ST elevation in lateral leads I, aVL and V5-6
- Reciprocal ST depression in inferior leads III and aVF
16
Q
Causes of prolonged QTc
A
- Drugs
- Electrolytes (K, Mg, Ca)
- Myocardial ischaemia
- Congenital QT syndrome
- Hypothermia
17
Q
Other waves
A
