Electrocardiogram

Question 1

What is the significance of the PR interval?

Answer 1

How fast signal is being conducted from atria to ventricles

Question 2

What is the significance of the QT interval?

Answer 2

All the electrical events that are occurring in the ventricle

Question 3

What does a wide QRS mean?

Answer 3

1. Something is wrong with the conduction system 2. Hypertrophy 3. Thin chest 4. Previous MI 5. Tamponade

Question 4

When would you see ST depression?

Answer 4

Subendocardial injury

Question 5

When would you see ST elevation?

Answer 5

Transmural (epicardial) injury

Question 6

What does hyperkalemia do to the QRS complex?

Answer 6

Widens - ventricular depolarization takes longer

Question 7

What does hyperkalemia do to the QT interval?

Answer 7

Shortens

Question 8

What does hypokalemia do to the T wave?

Answer 8

Decreases amplitude, possibly inverted

Question 9

What does hypercalcemia do to the ST segment?

Answer 9

Very abbreviated

Question 10

What does hypercalcemia do to the QT interval?

Answer 10

Really short

Question 11

What does hypocalcemia do to the ST segment?

Answer 11

Prolonged

Question 12

What does hypocalcemia do to the QT interval?

Answer 12

Prolonged

Question 13

How does a bundle branch block manifest on an ECG?

Answer 13

Every QRS is wide but preceded by a physiologic P wave