CRAT Ventricular Arrhythmia Identification 3

Question 1

The morphology of a PVC can provide information about where in the ventricle the ectopic focus is located. A PVC with LBBB morphology (negative QRS in V1) suggests the focus is located where?

Accepted Answer

Right ventricle

Answer

A PVC with LBBB morphology indicates the focus is in the right ventricle — the right ventricle activates first (making V1 negative as depolarization moves away), and the left ventricle activates later, similar to left bundle branch block pattern.

Question 2

Idioventricular rhythm (ventricular escape rhythm) is expected to fire at which rate range?

Accepted Answer

20-40 bpm

Answer

Ventricular escape pacemakers in the Purkinje fibers have the lowest intrinsic automaticity rate of 20-40 bpm, emerging when all higher pacemakers (SA node and AV junction) fail.

Question 3

Which clinical condition most commonly causes unifocal PVCs in hospitalized patients without structural heart disease?

Accepted Answer

Electrolyte disturbances (hypokalemia, hypomagnesemia)

Answer

Electrolyte abnormalities — particularly hypokalemia and hypomagnesemia — are among the most common reversible causes of PVCs in hospitalized patients, as they alter membrane potential stability.

Question 4

Ventricular flutter is best described by which ECG appearance?

Accepted Answer

Regular sinusoidal wide complex tachycardia at 200-300 bpm with no discernible QRS-T separation

Answer

Ventricular flutter appears as a regular, sinusoidal (smooth, continuous wave) wide complex tachycardia at 200-300 bpm where QRS complexes and T waves merge into continuous undulation without distinct separation.

Question 5

In patients with frequent PVCs, which marker is most predictive of adverse outcomes (increased risk of sudden cardiac death)?

Accepted Answer

Presence of underlying structural heart disease, particularly reduced left ventricular ejection fraction

Answer

The most important prognostic factor for PVC-related adverse outcomes is underlying structural heart disease, particularly reduced LVEF — PVCs in structurally normal hearts carry a relatively benign prognosis.

CRAT - Certified Rhythm Analysis Technician Practice Test

CRAT - Certified Rhythm Analysis Technician Practice Test

CRAT Ventricular Arrhythmia Identification 3