A 68-year-old woman comes to the office for follow-up after a recent emergency department visit. Two weeks ago, the patient experienced palpitations and mild dizziness; ECG showed atrial fibrillation with rapid ventricular response. The episode resolved spontaneously in 2 hours, and she has had no symptoms since then. The patient has a history of hypertension treated with valsartan and hydrochlorothiazide. She is a lifetime nonsmoker and does not drink alcohol. Her exercise tolerance is good. Blood pressure is 128/72 mm Hg, and pulse is 74/min and regular. Physical examination is unremarkable. TSH is 1.6, creatinine is 1.1 mg/dL, and fasting glucose is 85 mg/dL. Echocardiography shows preserved left ventricular ejection fraction and no significant valvular abnormalities. Which of the following is the best next step in management of this patient?

Question

A 68-year-old woman comes to the office for follow-up after a recent emergency department visit.  Two weeks ago, the patient experienced palpitations and mild dizziness; ECG showed atrial fibrillation with rapid ventricular response.  The episode resolved spontaneously in 2 hours, and she has had no symptoms since then.  The patient has a history of hypertension treated with valsartan and hydrochlorothiazide.  She is a lifetime nonsmoker and does not drink alcohol.  Her exercise tolerance is good.  Blood pressure is 128/72 mm Hg, and pulse is 74/min and regular.  Physical examination is unremarkable.  TSH is 1.6, creatinine is 1.1 mg/dL, and fasting glucose is 85 mg/dL.  Echocardiography shows preserved left ventricular ejection fraction and no significant valvular abnormalities.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d09d_2896_bc81_e98e2375495c_MD0003_00 This patient had an episode of atrial fibrillation that spontaneously resolved within hours. At the time of her clinic follow-up 2 weeks later, she appears to be in normal sinus rhythm (evidenced by a regular pulse rhythm). Given her age and other risk factors (eg, hypertension), this patient will most likely continue to have intermittent episodes of the arrhythmia (ie, paroxysmal atrial fibrillation). The risk of systemic thromboembolism (eg, stroke) is increased in atrial fibrillation, likely to a similar degree in both paroxysmal and persistent/permanent disease. Therefore, an important component in managing new-onset atrial fibrillation is an assessment of the need for chronic anticoagulation to lower that risk. In patients with nonvalvular atrial fibrillation, the CHA₂DS₂-VASc score is typically used to estimate annual risk, with chronic anticoagulation indicated for patients with a total score ≥2. Direct oral anticoagulants (eg, apixaban, rivaroxaban, dabigatran) are typically used for chronic anticoagulation, although warfarin is sometimes used instead. This patient has a CHA₂DS₂-VASc score of 3 (ie, hypertension, age, female sex); therefore, the initiation of apixaban is most appropriate (Choice F). Chronic anticoagulation is not indicated for patients with a CHA₂DS₂-VASc score of 0 and should be considered (but is not necessarily indicated) for patients with a score of 1. (Choice A) Ambulatory heart rhythm monitoring (eg, Holter monitor) is used to help diagnose an intermittent arrhythmia that has not been captured on ECG. This patient's atrial fibrillation has already been recognized on ECG and further diagnostic intervention is not needed. (Choice B) Amiodarone is sometimes used as a rhythm-control agent for atrial fibrillation. However, it has multiple side effects and is not a first-line agent. It is not indicated in this patient whose episode of atrial fibrillation has resolved. (Choice D) Aspirin is not significantly effective in lowering the risk of systemic thromboembolism in atrial fibrillation and should not be used for this purpose, particularly in patients with an elevated CHA₂DS₂-VASc score. (Choice E) Carotid ultrasound is not indicated in the management of new-onset atrial fibrillation. Stroke associated with atrial fibrillation occurs due to embolization of atrial thrombus and is independent of carotid artery atherosclerosis. Educational objective: The management of new-onset atrial fibrillation should involve an assessment of systemic thromboembolism risk. Chronic anticoagulation (eg, apixaban) should be initiated for patients with a CHA₂DS₂-VASc score ≥2 to lower their risk. References: Anticoagulation in atrial fibrillation. (http://www.ncbi.nlm.nih.gov/pubmed/24733535)

A 68-Year-Old Woman Comes to the Office for Follow-Up After