Ischaemic heart disease (Acute ST elevation MI, NSTEMI and ACS)

Question 1

ECG Tutorial: Steps To Read A Rhythm Strip

Answer 1

1. Is there any electrical activity
2. What is the ventricular rate (QRS)
3. Is it regular/irregular
4. Is the QRS narrow/broad
5. Is there any atrial activity (If so what, P
   waves, other)
6. What is the relationship between the
   atrium and ventricles

Question 2

ECG Tutorial: How to calculate heart rate

Answer 2

Regular:
• There are 300 large squares per minute.
• If the rhythm is regular count the number of large
squares between two QRS complexes and divide it into
300

Irregular:
• 30 large squares correspond to 6 seconds.
• Count the number of QRS complexes in 30 large
squares and multiply by 10

Question 3

ECG Tutorial: How do you know the ratio of atrial to ventricular beats in atrial flutter?

Answer 3

Example: atrial rate 300, ventricular 75 = 4:1

Question 4

ECG Tutorial: Is Mobitz I or II more worrying?

Answer 4

Mobitz I (Wenkebach) is mostly benign

Mobitz II - can turn into complete heart block or arrest, must be admitted for pacemaker

Question 5

ECG Tutorial: Treatment for Mobitz II

Answer 5

Tcan turn into complete heart block or arrest, must be admitted for pacemaker

reat: identify causes (electrolytes, ischaemia)
Get pacemaker ASAP
Externally pace them if required
- Isoprenaline works

Question 6

ECG Tutorial: How can you tell how many sources of ectopics there are in ventricular ectopics?

Answer 6

Monomorphic complexes - one focus of ectopics

Polymorphic - multi-focal ventricular ectopics

Question 7

ECG Tutorial: What is an idio-ventricular rhythm?

Answer 7

idio-ventricular rate (an escape rhythm)

75
regular
broad
no atrial activity

Normal ventricular is below 40, so this is accelerated idio-ventricular. If over 100 would be VT.

Question 8

ECG Tutorial: Management of VT

Answer 8

Ventricular Tachycardia (VT) 
Pulseless VT is cardiac arrest

Pulse VT is treated as medical emergency: if compromised treat with electricity, if not compromised treat with medication amiodarone
But tend to do both electrocardioversion and amiodarone prepared. Amiodarone 20 min infusion and if it doesn’t work you have DC ready.

Specialists use flecainide (requires recent ECHO to rule out structural heart disease), generalists use amiodarone

Question 9

ECG Tutorial: Overdose of what substance causes torsade de Pointes?

Answer 9

Tricyclic antidepressants

This is also seen in patients with long QT Syndrome

Treatment is sodium bicarb

Question 10

ECG Tutorial: What are the criteria for ST Elevation?

Answer 10

What is ST elevation?

• V1-V3 is 2 mm
• All others is 1 mm

Question 11

ECG Tutorial: What morphology of T waves signals they may be followed by ST elevation?

Answer 11

Hyperacute T waves, that then become asymmetrical lead to ST elevation

Question 12

ECG Tutorial: What are deep “arrow head” inverted T waves a sign of?

Answer 12

T wave symmetrical inversion deep arrow head shape

LAD syndrome, wellen’s sign - about to have big MI

Question 13

ECG Tutorial: How can you differentiate right vs left BBB?

Answer 13

With Wide:
If R predominantly negative in V1-V3, it is LBBB

If R predominantly positive, it is RBBB

Question 14

ECG Tutorial: What is a delta wave?

Answer 14

delta wave (slurred upstroke) following Kent not bundle of His.

Seen in Wolf Parkinson White

Will require ablation