ECG Question-1
Contents
- 1 What is the most probable diagnosis of ECG given below?
- 2 What is the mechanism of tenting of the T waves in hyperkalemia?
- 3 What is the mechanism of smaller P waves and widening of the QRS complex in hyperkalemia?
- 4 Peaked T waves in hyperkalemia are best seen in
- 5 What are the classic ECG changes associated with hyperkalemia?
- 6 What are the ECG findings associated with adverse outcomes?
- 7 Hyperkalemia severity –
What is the most probable diagnosis of ECG given below?
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A. Hypercalcemia
B. Hyperkalemia
C. Hypocalcemia
D. Hypokalemia
B. Hyperkalemia
C. Hypocalcemia
D. Hypokalemia
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Mikael Häggström, Public domain, via Wikimedia Commons
Mild to moderate hyperkalemia – prolongation of the PR interval and development of peaked T waves.
Severe hyperkalemia- widening of the QRS complex
What is the mechanism of tenting of the T waves in hyperkalemia?
A. Faster depolarisation
B. Slower repolarisation
C. Faster repolarisation
D. Slower repolarisation
What is the mechanism of smaller P waves and widening of the QRS complex in hyperkalemia?
A. Inactivation of potassium channels
B. Inactivation of sodium channels
C. Inactivation of calcium channels
D. Inactivation of Calcium-activated potassium channels
Peaked T waves in hyperkalemia are best seen in
A. Lead -I
B. Lead- II
C. aVF
D. Precordial leads
What are the classic ECG changes associated with hyperkalemia?
- Peaked T wave,
- Shortened QT interval,
- Lengthened PR interval,
- Increased QRS duration,
sine wave – absence of the P wave with the QRS complex seen as a ‘sine wave’.
What are the ECG findings associated with adverse outcomes?
Following ECG findings are associated with increased risk of adverse outcomes –
- Bradycardia,
- junctional rhythms
- QRS widening
Hyperkalemia severity –
Degree of hyperkalaemia | Potassium level (mmol/L) | ||
Mild | 5.3 – 6.0 | ||
Moderate | 6.0 – 6.9 | ||
Severe | ≥ 7.0 |