Study Questions: Chapter 03 Chapter 3: Approach to Patients with Extracranial Carotid Artery Disease ESTHER S.H. KIM, MD, MPH, FSVM Study Questions: Chapter 3 * 1.) Which of the following is the most common cause of stroke? Hemorrhagic Lacunar Thromboembolic Hypoperfusion from severe carotid artery stenosis Show answerThe correct answer is 3, Thromboembolic. Artery-to-artery embolism is the most common cause of stroke. The other choices are potential causes of stroke; however, they are less common. * 2.) An 80%‒99% right internal carotid artery stenosis is detected in a patient referred for carotid duplex ultrasonography. Which of the following should prompt a referral for revascularization? Age >70 years An ankle-brachial index of 0.75 History of prior coronary artery bypass grafting Amaurosis fugax Show answerThe correct answer is 4, Amaurosis fugax. Multiple large, randomized-controlled trials have shown benefit of revascularization (CEA and CAS) in symptomatic patients with severe carotid artery stenosis. While older patients and those with evidence of atherosclerotic disease are more likely to have carotid artery stenosis, the presence of these factors alone does not play a role in the decision for revascularization. * 3.) A 68-year-old man with history of tobacco abuse, hypertension, and hyperlipidemia presents for an annual clinic visit with vague symptoms suggestive of TIAs. Which of the following is a true statement? The absence of a carotid bruit on physical exam makes severe carotid artery stenosis unlikely. CTA of the neck is the initial diagnostic exam of choice. Carotid duplex ultrasonography will show elevated velocities and color turbulence at the mid and distal internal carotid artery. CTA or MRA is indicated if results of carotid duplex ultrasound are equivocal. Show answerThe correct answer is 4, CTA or MRA is indicated if results of carotid duplex ultrasound are equivocal. Carotid duplex ultrasonography has excellent sensitivity and specificity for the detection of carotid artery stenosis. CTA or MRA is indicated when results of CDU are equivocal. The absence of a carotid bruit does not preclude the diagnosis of a severe carotid artery stenosis; more than one-third of patients in a NASCET substudy with severe carotid artery stenosis did not have a cervical bruit on physical examination. Due to the requirement for iodinated contrast and radiation exposure, CTA is not the initial diagnostic examination of choice for the detection of carotid artery stenosis. This patient most likely has atherosclerotic carotid artery disease, which most commonly affects the origin of the internal carotid artery; findings of elevated velocities and color turbulence at the mid and distal internal carotid artery are consistent with fibromuscular dysplasia. * 4.) A 67-year-old man with history of hypertension, hyperlipidemia, and smoking presents with an asymptomatic left cervical bruit. Carotid duplex ultrasound shows a 60%‒79% stenosis of the left internal carotid artery. In addition to starting aspirin and an antihypertensive agent, which of the following medical regimens is optimal? Statin, warfarin Statin, warfarin, smoking cessation counseling Statin, smoking cessation counseling Clopidogrel, smoking cessation counseling Show answerThe correct answer is 3, Statin, smoking cessation counseling. Answers 1 and 2 are incorrect, as there is no benefit of warfarin over aspirin for the secondary prevention of stroke, in the absence of other indications for anticoagulation. Answer 4 is incorrect, as 2 large randomized-controlled trials of the combination of aspirin plus clopidogrel did not show improved stroke prevention over either antiplatelet used alone. * 5.) For which of the following scenarios may it be more appropriate to perform carotid endarterectomy over carotid artery stenting? Prior radiation to the neck Markedly tortuous aortic arch vessels arising from the aorta with severe angulation Restenosis of the internal carotid artery after prior ipsilateral carotid endarterectomy Chronic total occlusion of the targeted carotid artery Show answerThe correct answer is 2, Markedly tortuous aortic arch vessels arising from the aorta with severe angulation. Tortuous arteries with severe angulation off the aorta make placement of carotid stents challenging, and carotid endarterectomy is preferred in these patients. Patients with prior radiation to the neck and restenosis at a site of prior carotid endarterectomy have anatomy unfavorable for operative intervention. Carotid revascularization is not recommended for patients with chronic total occlusion of the targeted carotid artery.