Review Question - QID 109845

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Atrial Fibrillation QID: 109845 (M2.CV.17.4869)

QID 109845 (Type "109845" in App Search)

A 55-year-old man with no significant medical history presents to the hospital for an elective total right knee replacement. He works as a construction worker and said that frequent kneeling and squatting has caused his knees to wear out faster. He has not had anything to eat since last night. After consent is obtained for regional anesthesia via an adductor canal block, monitors are applied, which shows that his pulse is 100/min with a pattern shown in Figure A. Blood pressure is 120/70 mmHg, respirations are 14/min, and oxygen saturation is 100%. A 12-lead electrocardiogram is in Figure A. The surgery is canceled. Further laboratory workup and echocardiography reveals no findings. Which of the following is the most appropriate next step in management?

Type & Select Correct Answer

Type in at least one full word to see suggestions list

Amiodarone

2/57

Amiodarone and warfarin

30%

17/57

Metoprolol

30%

17/57

Metoprolol and heparin

16%

9/57

Metoprolol and rivaroxaban

21%

12/57

Select Answer to see Preferred Response

This hemodynamically stable patient is found to have paroxysmal atrial fibrillation with a CHA2DS2-VASc score of 0. In the absence of other indications for anticoagulation management, a rate control agent such as metoprolol is all that is indicated.

Long-term management of atrial fibrillation includes rate control along with anticoagulation. Anticoagulation serves to decrease the risk of thromboembolism. The CHA2DS2-VASc score allows for stroke risk stratification, including the following criteria: age > 65 years, sex, presence of congestive heart failure, hypertension, diabetes, and/or vascular disease, and a past episode of stroke/transient ischemic attack/thromboembolism. For patients with a score of 0 or 1, conservative management or daily aspirin use is recommended. When managing atrial fibrillation, rate control with agents such as metoprolol or diltiazem is generally preferred as rate control agents have a preferred side effect profile and can have mortality-lowering benefits pending the patient's other risk factors.

Wyse et al. review the evidence regarding the diagnosis and treatment of patients with atrial fibrillation. They discuss how both rate and rhythm control agents have been used with success in this disorder. They recommend using beta blockers to trial rate control in low-risk patients.

Figure/Illustration A shows a rhythm strip revealing atrial fibrillation without P waves and irregularly irregular QRS complexes (note the irregular spacing between the blue arrows).

Incorrect Answers
Answer 1: Amiodarone is a rhythm control agent with many side effects including photosensitivity, hypothyroidism, and pulmonary fibrosis with an increased incidence of side effects with chronic use. It could be a viable strategy to control atrial fibrillation acutely in some patients who cannot tolerate rate control agents.

Answer 2: Amiodarone and warfarin would not be optimal. This treatment regimen represents rhythm control which is not preferred when compared to rate control and his CHA2DS2-VASc score is too low to warrant anticoagulation.

Answer 4: Metoprolol and heparin would not be indicated in this patient as anticoagulation is not needed given his CHA2DS2-VASc score.

Answer 5: Metoprolol and rivaroxaban would be inappropriate as this patient does not need anticoagulation given his CHA2DS2-VASc score. Rivaroxaban is an appropriate agent for anticoagulation given its easy dosing.

Bullet Summary:
Patients with atrial fibrillation and a CHA2DS2-VASc score of 0 can be managed with no anticoagulation or daily aspirin and a rate control agent.