ECG II and Arrhythmia Flashcards
What is the reason for a broad and bifid P wave?
Left atrial hypertrophy, usually due to mitral stenosis
What is the shape of the P wave in right atrium hypertrophy?
P wave becomes peaked
What is the effect of Digoxin on the ECG?
DIgoxin causes T wave inversion with characteristic sloping depression of the ST segment.
Which electrolyte abnormalities will affect the ECG?
How will the ECG be affected?
Abnormalities in the plasma levels of potassium, calcium and magnesium affects the ECG.
Changes in the plasma sodium level does not.
Low potassium level causes T wave flattening and the appearance of a hump on the end of the T wave, called a U wave.
High potassium level causes peaked T waves with the disappearance of ST segment. QRS complex may also be widened.
Same effects for abnormal magnesium levels.
Low plasma calcium level causes prolongation of QT interval and a high plasma calcium level shortens it.
State if the following are normal or abnormal:
- Inverted T wave in aVL
- Inverted T wave in lead V1
- Inverted T wave in aVL is abnormal
2. Inverted T wave in Lead V1 is normal
What is the issue if there is a horizontal depression of ST segment?
How about a downward sloping ST depression?
A horizontal ST depression is seen in ischaemia as opposed to infarction.
A downward sloping ST segment is usually due to treatment with Digoxin.
What is used to treat sinus bradycardia?
Sinus bradycardia is treated with Atropine 0.6-1.2mg IV.
Which type of heart block: Mobitz type I or Mobitz type II will require cardiac pacing? Why?
Mobitz type II will require cardiac pacing as there is a high risk of developing into complete AV block.
Mobitz type I does NOT require pacing unless poorly tolerated.
1st degree heart block is most commonly seen in which condition?
Inferior MI
Risk of Digitalis toxicity will increase in which conditions?
Risk of Digitalis toxicity increases with Hypokalaemia, Hypomagnesaemia and Hypercalcaemia
