A 72-year-old man comes to the emergency department due to severe left lower leg pain that began as a tingling sensation several hours ago but has since become increasingly painful. Medical history is significant for hypertension, type 2 diabetes mellitus, paroxysmal atrial fibrillation, and osteoarthritis. The patient has a 45-pack-year smoking history. Blood pressure is 142/80 mm Hg, and pulse is 112/min and irregular. On physical examination, the left lower extremity skin appears mottled and is cool to the touch. The distal pulses of the left leg are not palpable. There is a right carotid bruit. Which of the following medications could have best prevented this patient's acute condition?

Question

A 72-year-old man comes to the emergency department due to severe left lower leg pain that began as a tingling sensation several hours ago but has since become increasingly painful.  Medical history is significant for hypertension, type 2 diabetes mellitus, paroxysmal atrial fibrillation, and osteoarthritis.  The patient has a 45-pack-year smoking history.  Blood pressure is 142/80 mm Hg, and pulse is 112/min and irregular.  On physical examination, the left lower extremity skin appears mottled and is cool to the touch.  The distal pulses of the left leg are not palpable.  There is a right carotid bruit.  Which of the following medications could have best prevented this patient's acute condition?

Quizplus · Accepted Answer

11ec25c8_d170_7e01_bc81_859bc126628d_MD0003_00 This patient with acute lower extremity pain, paresthesia, and pulselessness has acute limb ischemia. Given the patient's history of paroxysmal atrial fibrillation (AF) and irregular pulse on examination, the most likely cause is embolism of a left atrial thrombus, which might have been prevented by appropriate anticoagulation therapy. Current guidelines recommend the use of the CHA₂DS₂-VASc score for thromboembolic risk assessment in patients with AF. Patients with a CHA₂DS₂-VASc score ≥2, such as this patient (score = 3: hypertension, diabetes mellitus, age 65-74), are at high risk of thromboembolic events and should be managed with anticoagulation therapy. In these patients, the benefit of lowered embolization risk outweighs the risk of bleeding (eg, intracranial hemorrhage). anticoagulation therapy Apixaban is a non-vitamin K antagonist oral anticoagulant (NOAC) that directly inhibits factor Xa, preventing it from cleaving prothrombin to thrombin. The NOACs (eg, apixaban, dabigatran, rivaroxaban, edoxaban) significantly reduce systemic embolization risk with similar or superior efficacy as warfarin but with decreased risk of severe bleeding (eg, hemorrhagic stroke) and no need for routine INR testing. In contrast, antiplatelet therapy with aspirin or a combination of aspirin and clopidogrel is significantly less effective in reducing thromboembolic risk compared with anticoagulant therapy with NOACs or warfarin (Choices B and D). directly inhibits factor Xa (Choice C) Cilostazol is a phosphodiesterase inhibitor occasionally used for symptomatic management of patients with intermittent claudication. Although cilostazol also suppresses platelet aggregation, it is not indicated for primary thromboembolic event prevention in patients with AF. (Choices E and F) Calcium channel blockers (eg, diltiazem) and beta blockers (eg, metoprolol) are used for heart rate control in patients with AF. Rate control helps manage symptoms and avoid hemodynamic instability from rapid ventricular response; however, unlike anticoagulation, it does not prevent thromboembolic events. Educational objective: Anticoagulation agents, such as non-vitamin K antagonist oral anticoagulants (eg, apixaban) and warfarin, should be used to reduce the risk of systemic thromboembolism in patients with atrial fibrillation and a high risk of thromboembolic events (ie, CHA₂DS₂-VASc score ≥2). References: 2019 AHA/ACC/HRS focused update of the 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on clinical practice guidelines and the Heart Rhythm Society. (http://www.ncbi.nlm.nih.gov/pubmed/30703530)

A 72-Year-Old Man Comes to the Emergency Department Due to Severe