AF Treatment Protocols & Procedures 3 — Questions and Answers
Question 1: Which rate-control target is generally recommended for most patients with AF according to current guidelines?
- Resting HR <60 bpm
- Resting HR <80 bpm
- Resting HR <100 bpm
- Resting HR <110 bpm (Correct answer)
Correct answer: Resting HR <110 bpm
A lenient rate-control target of resting HR <110 bpm is acceptable for most AF patients and was shown to be non-inferior to strict control in the RACE II trial.
Question 2: Ibutilide IV is used for pharmacological cardioversion of AF. What potentially life-threatening side effect requires monitoring after administration?
- Hyperkalemia
- Torsades de pointes (Correct answer)
- Pulmonary edema
- Renal failure
Correct answer: Torsades de pointes
Ibutilide prolongs the QT interval and can precipitate polymorphic ventricular tachycardia (torsades de pointes), requiring continuous ECG monitoring after administration.
Question 3: In a hemodynamically unstable patient with rapid AF, what is the immediate treatment priority?
- IV amiodarone infusion
- Oral metoprolol loading dose
- Synchronized DC cardioversion (Correct answer)
- Transesophageal echocardiogram first
Correct answer: Synchronized DC cardioversion
Hemodynamic instability (hypotension, chest pain, altered consciousness) from rapid AF mandates immediate synchronized DC cardioversion regardless of anticoagulation status.
Question 4: Digoxin is least effective for rate control during which condition commonly encountered in AF patients?
- Sleep
- Rest
- Exercise (Correct answer)
- Supine positioning
Correct answer: Exercise
Digoxin controls ventricular rate primarily via vagal tone and is ineffective during exercise when sympathetic drive overrides its effect.
Question 5: A transesophageal echocardiogram (TEE) before cardioversion is performed to rule out which specific finding?
- Mitral stenosis
- Left atrial appendage thrombus (Correct answer)
- Pericardial effusion
- Aortic regurgitation
Correct answer: Left atrial appendage thrombus
TEE is used to exclude left atrial appendage (LAA) thrombus before cardioversion, which if present could embolize and cause stroke during rhythm restoration.
Question 6: Which class of antiarrhythmic drug is contraindicated in patients with AF and Wolff-Parkinson-White (WPW) syndrome?
- Class IA agents
- Class IC agents
- AV nodal blocking agents (digoxin, beta-blockers, calcium channel blockers) (Correct answer)
- Class III agents
Correct answer: AV nodal blocking agents (digoxin, beta-blockers, calcium channel blockers)
AV nodal blockers are contraindicated in WPW with AF because they can accelerate conduction down the accessory pathway, potentially causing ventricular fibrillation.
Question 7: After successful AF ablation, what is the typical 'blanking period' during which recurrent AF episodes are not considered procedural failure?
- 1 week
- 2 weeks
- 4 weeks
- 3 months (Correct answer)
Correct answer: 3 months
The 3-month post-ablation blanking period accounts for early recurrences caused by inflammatory changes and edema at ablation sites, which often resolve.
AF Treatment Protocols & Procedures 3
Which rate-control target is generally recommended for most patients with AF according to current guidelines?