Atrial Fibrillation: A Spot Quiz

April 19, 2017

Your atrial fibrillation spot quiz of the week -- take a minute and try these 3 short questions.

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If you've got a minute, take our spot quiz on atrial fibrillation.

1. Which of the following statement(s) regarding atrial fibrillation is/are true?

A. In the US, 2.3 million people have atrial fibrillation and the number is expected to increase to 5.6 million by 2050.

B. Atrial fibrillation is associated with a 5-fold greater risk for stroke.

C. Atrial fibrillation is associated with a 2-fold greater risk for all-cause mortality.

D. Fifty percent of patients with atrial fibrillation have structural heart disease.

Click here for answer and question #2.

 

Answer: A, B, and C are true; D is false1

Eighty percent of patients with atrial fibrillation have structural heart disease.1 Atrial fibrillation is not only the most common clinically significant arrhythmia, but left untreated, its complications are serious.

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2. After a diagnosis of atrial fibrillation is made, what lab studies should be ordered?

A. Serum electrolytes

B. Thyroid stimulating hormone

C. Renal and hepatic function.

D. Stool for occult blood

Click here for answer and question #3.

 

Answer: All the tests listed should be ordered after a diagnosis of atrial fibrillation.

Renal and hepatic function, as well as tests for occult blood, are important because many patients with atrial fibrillation will be on oral anticoagulation. If there is liver disease, the INR may be prolonged. The direct-acting oral anticoagulants or DOACs (eg, rivaroxaban) depend on renal excretion.

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3. Regarding anticoagulation and stroke risk in atrial fibrillation, which of the following statement(s) is/are true?

A. Patients with atrial fibrillation receiving warfarin have 64% fewer strokes than patients with atrial fibrillation receiving antiplatelet agents.

B. Among the 4 DOACs, three (rivaroxaban, apixaban, and edoxaban) are Factor Xa inhibitors and dabigatran is a direct thrombin inhibitor.

C. The risk for intracranial bleeding is the same for warfarin and the DOACS.

D. The DOACS can be used in patients with atrial fibrillation and a mechanical valve.

Click here for answer.

 

Answers: A and B are true; C and D are false. 

The direct thrombin and factor Xa inhibitors have a more favorable bleeding profile than warfarin; they are, however, contraindicated in persons with mechanical valves.

 

The source for this short quiz, the “In the Clinic” feature on the Annals of Internal Medicine webiste, provides excellent material on the diagnosis and treatment of atrial fibrillation.

Zimetbaum P. In The Clinic: Atrial  fibrillation. Ann Intern Med. 2017;166:ITC33-ITC48. DOI: 10.7326/AITC201703070 (abstract; full access requires subscription)