AF Diagnosis & Risk 2 — Questions and Answers
Question 1: Which ECG finding is most characteristic of atrial fibrillation?
- Absent P waves with irregularly irregular RR intervals (Correct answer)
- Regular RR intervals with wide QRS complexes
- Peaked P waves with prolonged PR interval
- Delta waves with short PR interval
Correct answer: Absent P waves with irregularly irregular RR intervals
AF is defined by chaotic atrial activity resulting in absent discrete P waves and an irregularly irregular ventricular response.
Question 2: A patient with AF has a CHADS2 score of 3. Which component contributes 2 points to this score?
- Prior stroke or TIA (Correct answer)
- Congestive heart failure
- Diabetes mellitus
- Age ≥75 years
Correct answer: Prior stroke or TIA
In the CHADS2 score, prior stroke or TIA carries 2 points, while CHF, hypertension, age ≥75, and diabetes each carry 1 point.
Question 3: Which imaging modality is preferred to rule out left atrial appendage thrombus before cardioversion?
- Transesophageal echocardiography (TEE) (Correct answer)
- Transthoracic echocardiography (TTE)
- Cardiac MRI
- CT angiography of the chest
Correct answer: Transesophageal echocardiography (TEE)
TEE provides superior visualization of the left atrial appendage compared to TTE and is the standard for excluding LAA thrombus prior to cardioversion.
Question 4: A 68-year-old male with AF, hypertension, and no other comorbidities has a CHA2DS2-VASc score of:
- 3 (Correct answer)
- 2
- 1
- 4
Correct answer: 3
He scores 1 for male sex (vascular category), 1 for age 65-74, and 1 for hypertension, totaling 3 points.
Question 5: Which condition is considered a major risk factor for developing AF due to atrial pressure overload?
- Mitral stenosis (Correct answer)
- Aortic regurgitation
- Tricuspid regurgitation
- Pulmonic stenosis
Correct answer: Mitral stenosis
Mitral stenosis causes left atrial pressure and volume overload, leading to atrial dilation and structural remodeling that promotes AF.
Question 6: Holter monitoring over 24-48 hours is most appropriate for detecting AF in which clinical scenario?
- Palpitations occurring daily or every other day (Correct answer)
- Palpitations occurring once a month
- Evaluation of known persistent AF rate control
- Asymptomatic patient with no suspected arrhythmia
Correct answer: Palpitations occurring daily or every other day
Holter monitoring captures continuous rhythm data for 24-48 hours, making it ideal for symptoms occurring frequently (daily to every other day).
Question 7: Which serum biomarker has been associated with increased risk of AF and atrial fibrosis?
- NT-proBNP (Correct answer)
- Troponin I
- D-dimer
- Homocysteine
Correct answer: NT-proBNP
Elevated NT-proBNP reflects atrial wall stress and is associated with atrial remodeling, increased AF risk, and worse outcomes.
AF Diagnosis & Risk 2
Which ECG finding is most characteristic of atrial fibrillation?