CRAT ECG Interpretation 3

Question 1

Right bundle branch block (RBBB) produces which classic ECG pattern?

Accepted Answer

RSR' (rabbit ears) pattern in V1 and wide S waves in leads I, aVL, and V6

Answer

Broad notched R in lateral leads with QS in V1

Answer

Delta waves and short PR interval

Answer

Peaked T waves and widened QRS

Question 2

The QTc (corrected QT) is used to adjust for heart rate. Using Bazett's formula, QTc is prolonged when it exceeds which threshold in adults?

Accepted Answer

440-450 ms (with upper limits: 450 ms in men, 460 ms in women)

Answer

360 ms

Answer

500 ms in all patients

Answer

PR interval × heart rate

Question 3

Wolff-Parkinson-White (WPW) syndrome produces which classic triad of ECG findings?

Accepted Answer

Short PR interval (< 120 ms), delta wave (slurred QRS upstroke), and wide QRS complex

Answer

Long PR interval, narrow QRS, and peaked T waves

Answer

Short PR, inverted P waves, and narrow QRS

Answer

Delta waves only with normal PR interval

Question 4

In a patient with suspected hyperkalemia, which ECG finding appears first as potassium rises from normal levels?

Accepted Answer

Peaked, narrow, symmetric T waves

Answer

Widened QRS complex

Answer

Prolonged PR interval

Answer

Flat P waves

Question 5

Brugada syndrome is associated with which pattern on ECG?

Accepted Answer

Coved ST elevation in V1-V3 (Type 1 Brugada pattern) with right bundle branch block morphology

Answer

ST depression in inferior leads

Answer

Prolonged QT with torsades

Answer

Delta waves with short PR interval

Question 6

The axis of the heart on a 12-lead ECG is considered to have left axis deviation when it falls within which range?

Accepted Answer

-30 degrees to -90 degrees (or beyond -30 to -180 degrees depending on criteria)

Answer

0 to +90 degrees

Answer

+90 to +180 degrees

Answer

-90 to -180 degrees exclusively