A 29-year-old man comes to clinic 2 weeks after an emergency department visit for epistaxis requiring anterior nasal packing. In the emergency department, his blood pressure was 170/110 mm Hg. He has occasional headaches and fatigue but no chest pain, palpitations, or syncope. His medical history is unremarkable and he does not use tobacco, alcohol, or recreational drugs. The patient's current blood pressure is 180/112 mm Hg and pulse is 78/min and regular. Cardiac auscultation in the supine position reveals no murmurs or additional sounds. Abdominal examination shows no periumbilical bruits. Laboratory results are as follows:
| Hemoglobin | 14.2 g/dL |
| Platelets | 230,000/mm3 |
| Creatinine | 1.0 mg/dL |
Urine toxicology screen is negative. ECG shows normal sinus rhythm, high-voltage QRS complexes, and downsloping ST-segment depression as well as T wave inversion in leads V5 and V6. Which of the following is the best next step in evaluation of this patient?
Coarctation of the aorta | |
Etiology |
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Clinical features |
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Diagnostic studies |
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Treatment |
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This patient's elevated blood pressure and ECG findings consistent with left ventricular hypertrophy (LVH) (eg, high-voltage QRS complexes, lateral ST segment depression, lateral T wave inversion) are suggestive of long-standing systemic hypertension. Essential hypertension rarely leads to end-organ damage (eg, LVH) in young patients (eg, age <40), and therefore a cause of secondary hypertension should be sought.
Coarctation of the aorta is a narrowing of the descending aorta (typically located just distal to the origin of the left subclavian artery) that results in a proximal increase in arterial pressure and decreased blood flow to the lower body. Patients usually present with asymptomatic hypertension; however, epistaxis, headaches, and lower extremity claudication can occur. A continuous murmur is characteristically associated with coarctation but is not always noted and may be particularly difficult to auscultate in the supine position. Patients should be initially evaluated for coarctation of the aorta with:
Simultaneous palpation of the brachial and femoral pulses to assess for brachial-femoral delay
Bilateral upper extremity (supine position) and lower extremity (prone position) blood pressure measurement to evaluate for upper and lower extremity blood pressure differential
Patients with abnormal findings should undergo diagnostic confirmation with echocardiogram.
(Choice A) Ambulatory blood pressure monitoring is sometimes used for patients in whom the diagnosis of hypertension is uncertain. It is not indicated in this patient with significantly elevated blood pressure and evidence of LVH.
(Choice C) Squatting increases the volume of blood in the left ventricle and allows for differentiating the systolic murmur of aortic stenosis (intensifies with squatting, lessens with standing) from that of hypertrophic cardiomyopathy (lessens with squatting, intensifies with standing). This patient's epistaxis, headaches, and systemic hypertension are more suggestive of aortic coarctation.
(Choice D) Carotid sinus massage slows atrioventricular node conduction and can sometimes terminate paroxysmal supraventricular tachycardia (eg, atrioventricular nodal reentrant tachycardia). However, it is not useful in the evaluation or treatment of hypertension.
(Choice E) Exercise stress testing is often used to evaluate for coronary artery disease; however, this patient's ECG changes are more suggestive of LVH. In addition, coronary artery disease is very unlikely in this young patient, especially in the absence of chest pain.
Educational objective:
Coarctation of the aorta is a potential cause of secondary hypertension in young adults. Patients should be initially evaluated with simultaneous palpation of the brachial and femoral pulses to assess for brachial-femoral delay, and bilateral upper and lower extremity blood pressure measurement to assess for blood pressure differential.