A 19-year-old woman comes to the clinic due to recurrent headaches. The patient has had headaches for years but thinks they have recently gotten worse; they last several hours and remit spontaneously or after taking over-the-counter acetaminophen. She has no nausea, vomiting, abdominal pain, sweating, or fever. Six months ago, the patient checked her blood pressure at a local pharmacy and was told it was high. She has no other medical issues and takes no prescription medications. Her family history is significant for hypertension and diabetes. Blood pressure is 175/100 mm Hg on the right arm and 170/102 mm Hg on the left arm, pulse is 80/min, and respirations are 14/min. On examination, she appears comfortable and cooperative. Peripheral pulses are full and symmetric. Chest examination is unremarkable. A systolic bruit is heard under the right ear. Abdominal examination shows no tenderness or masses. Which of the following is the most likely cause of this patient's hypertension?
Fibromuscular dysplasia | |
Clinical presentation |
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Physical examination |
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Diagnosis |
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Treatment |
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| ARB = angiotensin II receptor blocker; CTA = CT angiography; MRA = MR angiography; PTA = percutaneous transluminal angioplasty; US = ultrasonography. | |
This patient most likely has secondary hypertension due to fibromuscular dysplasia (FMD). FMD is a systemic noninflammatory disease that typically affects the renal and internal carotid arteries and leads to arterial stenosis, aneurysm, or dissection. Less commonly, the vertebral, iliac, or mesenteric arteries can be affected.
In adults, approximately 90% of FMD cases occur in women. Recurrent headache caused by carotid artery stenosis or aneurysm is the most common presenting symptom. Pulsatile tinnitus, neck pain, or flank pain are also common, and symptoms of transient ischemic attack (eg, focal weakness, vision loss) may occur. Hypertension results from renal artery stenosis (RAS) leading to secondary hyperaldosteronism. An abdominal bruit may be present. In young patients, a subauricular systolic bruit is highly suggestive of FMD as carotid atherosclerosis should not be present. Even in older patients, such a bruit suggests FMD as the subauricular location indicates involvement of the internal carotid artery, which, in contrast with the carotid bulb, is not commonly affected by atherosclerosis.
Diagnosis of FMD is typically made by vascular imaging (eg, duplex ultrasonography, CT or magnetic resonance angiography). For patients with hypertension, treatment involves antihypertensive medication (eg, ACE inhibitor) and definitive management of RAS with either percutaneous transluminal angioplasty or surgery.
(Choice A) Aortic coarctation presents with upper extremity hypertension, headaches, and lower extremity claudication. This patient has full peripheral (upper and lower extremity) pulses, making aortic coarctation unlikely.
(Choice C) Pheochromocytomas cause secondary hypertension due to secretion of catecholamines. Typical presentation is with episodic headaches, sweating, and tachycardia. A carotid bruit is not typical.
(Choice D) Primary hyperaldosteronism (adrenal adenoma) is associated with secondary hypertension, hypokalemia, and metabolic alkalosis. Bruits are not typical.
(Choice E) RAS due to atherosclerosis can cause secondary hypertension. However, renal atherosclerosis is extremely unlikely in this young woman in the absence of a familial hypercholesterolemia.
Educational objective:
In adults, fibromuscular dysplasia most commonly affects women. Headaches due to internal carotid artery stenosis and secondary hypertension due to renal artery stenosis are common presentations. Accompanying bruits may be found in the neck and abdomen.