A 35-year-old man presents to the emergency department for evaluation of chest pain. The pain starts in his chest and moves into his back, arms, and abdomen. He describes the pain as tearing. He has no known medical history and takes no medications. His temperature is 37.0°C (98.6°F), pulse is 130/min, blood pressure is 210/145 mmHg, respirations are 22/min, and pulse oximetry is 98% on room air. Exam reveals a diaphoretic, anxious-appearing man. Pulses are diminished over the left wrist when compared to the right. A chest radiograph is obtained as shown in Figure A. Which of the following is the most appropriate next step in management?
Aspirin
CT angiography of the chest, abdomen, and pelvis
Echocardiography
Lorazepam
CT angiography of the chest, abdomen, and pelvis
This patient with "tearing" chest pain, hypertension, and a chest radiograph demonstrating mediastinal widening likely has an aortic dissection. The most appropriate next step in management would be to obtain CT angiography of the chest, abdomen, and pelvis to confirm the diagnosis.

Aortic dissections develop due to a tear in the intimal layer of the aorta, causing a second blood-filled lumen to form. Risk factors include hypertension, trauma, Marfan syndrome, Turner syndrome, and pregnancy. Prognosis depends on the location and severity of the intimal tear. Aortic dissections are often described by using the Stanford classification, where Type A involves the ascending aorta and Type B involves tears distal to the left subclavian artery. Patients classically present with chest pain described as "tearing" or "ripping" with radiation into the back, arms, or abdomen. Hypertension is common. Chest radiography characteristically demonstrates widening of the mediastinum due to accumulation of blood between layers of the wall of the aorta. Type A dissections are managed with heart rate control, blood pressure control, and surgery. Type B dissections are managed with blood pressure and heart rate control only.

Cooper et al. report on aortic dissections in adolescence. Although rare, aortic dissections have been seen in children with congenital heart disease, connective tissue disorders, or severe traumatic accidents. Severe, migrating abdominal pain should heighten suspicion for this diagnosis. The patient will often look worse clinically than can be explained by physical findings.

Figure A depicts a chest radiograph demonstrating a widened superior mediastinum.

Incorrect Answers:
Answer A: Aspirin is administered for chest pain that is thought to be due to acute coronary syndrome. This patient's presentation, exam, and imaging findings suggest aortic dissection. Aspirin is contraindicated in aortic dissection due to the increased risk for bleeding.

Answer C: Echocardiography offers information on cardiac contractility, valve function, and the presence of effusions. It would not be an appropriate initial diagnostic test in aortic dissection. Transesophageal echocardiography may be used to make the diagnosis in patients who cannot undergo a CTA.

Answer D: Lorazepam would be appropriate for patients presenting with chest pain that is secondary to use of cocaine or other sympathomimetic drugs. Tachycardia, tachypnea, diaphoresis, hyperactive bowel sounds, and dilated pupils suggest a sympathomimetic toxidrome.

Answer E: Serum troponin testing is indicated for risk stratification of patients with suspected acute coronary syndrome.

Bullet Summary:
The most appropriate next step in management for patients with suspected aortic dissection and mediastinal widening on chest radiograph is CT angiography of the chest, abdomen, and pelvis.