CMC Cardiac Arrhythmia Management 2

Question 1

A patient with atrial fibrillation has a heart rate of 130 bpm and is hemodynamically stable. The onset is confirmed to be 36 hours ago. What is the preferred initial management?

Accepted Answer

Rate control and anticoagulation per CHA2DS2-VASc score before cardioversion

Answer

For atrial fibrillation with onset greater than 48 hours (or unknown duration), anticoagulation for at least 3 weeks or TEE to rule out thrombus is required before cardioversion due to risk of thromboembolism; rate control is appropriate in the interim.

Question 2

During post-cardiac surgery monitoring, a patient develops a wide-complex tachycardia at 200 bpm. Which ECG finding most strongly suggests ventricular tachycardia rather than SVT with aberrancy?

Accepted Answer

AV dissociation visible on the tracing

Answer

AV dissociation — independent atrial and ventricular activity — is a hallmark of ventricular tachycardia and essentially excludes supraventricular tachycardia with aberrant conduction.

Question 3

A patient with an implanted ICD receives multiple appropriate shocks for sustained VT. After stabilization, which long-term management strategy is most indicated to reduce recurrent ICD therapies?

Accepted Answer

Catheter ablation of the VT focus

Answer

Catheter ablation targets and eliminates the reentrant circuit or ectopic focus responsible for recurrent VT, significantly reducing ICD shocks and improving quality of life in patients with structural heart disease.

Question 4

Which AV block pattern is characterized by a progressively lengthening PR interval followed by a dropped QRS complex?

Accepted Answer

Mobitz type I (Wenckebach) second-degree AV block

Answer

Mobitz type I (Wenckebach) second-degree AV block features progressive PR interval lengthening until a P wave fails to conduct and a QRS is dropped, then the cycle repeats.

Question 5

A 68-year-old patient with hypertension and prior stroke has new-onset atrial fibrillation. What CHA2DS2-VASc score should prompt initiation of anticoagulation?

Accepted Answer

Score of 2 or greater

Answer

Current ACC/AHA guidelines recommend oral anticoagulation for patients with non-valvular AFib and a CHA2DS2-VASc score ≥2 in men (or ≥3 in women) due to meaningful annual stroke risk.

CMC - Cardiac Medicine Certification Practice Test

CMC - Cardiac Medicine Certification Practice Test

CMC Cardiac Arrhythmia Management 2