A 59-year-old man presented to the emergency department with complaints of sudden onset pain on the right side of the buttocks and the inability to move his right leg without great pain. He also described numbness in his right leg and foot. The symptoms had lasted approximately 30 minutes prior to arrival. Soon after presentation, the patient also developed mild midsternal chest pain with radiation to his back. The patient thought the pain in his buttocks was caused by sciatica, for which he had seen a chiropractor in the past. However, the patient described the pain as more intense than that associated with his prior sciatica-related back complaint. In addition to sciatica, the patient had a history of hypertension, migraines, and an enlarged prostate. Past surgical procedures included a cholecystectomy. The patient was taking metoprolol (25 mg daily) to control his blood pressure.
Initial vital signs included the following: temperature, 97.4°F (36.3°C); pulse, 61 beats per minute; respiration, 16 breaths per minute; and blood pressure, 157/50 mm Hg. He rated the pain in his leg as 8 out of 10 on a visual analog scale, with 10 indicating extreme pain. Results from physical examination were notable for generalized diaphoresis. Findings from head, neck, cardiovascular, lung, and abdominal examinations were normal. Strength of pulses palpated on the left upper and left lower extremities were normal (2+). On the right upper extremity, strength of the radial pulse was decreased but present (1+). We were unable to palpate dorsalis pedis or popliteal pulses on the right (0). We were also unable to obtain a pulse in these regions using handheld Doppler ultrasonography. The patient had a greatly diminished right femoral pulse by palpation. Range of motion in all extremities was equal, but sensation in the right lower extremity was decreased.
Laboratory test results were normal for complete blood cell count, comprehensive metabolic profile, international normalized ratio, and troponin I (0.02 ng/mL). Laboratory values were elevated for creatinine kinase (351 U/L) and creatinine kinase-MB fraction (8.7 ng/mL). Results of a portable chest radiograph were normal (
Figure 1).
Results of the electrocardiogram showed sinus bradycardia without ST-T segment abnormalities. The patient underwent a computed tomography angiogram of the thorax, abdomen, and pelvis. Results of the computed tomography angiogram of the chest showed a Stanford type A aortic dissection involving the left subclavian artery (
Figure 2). In addition, the patient had a dissection flap extending into the aberrant right subclavian artery, which had a retroesophageal tract (
Figure 2). He also had a common origin for the common carotid arteries (
Figure 2). The dissection continued into the abdomen and extended into the left renal artery approximately 3 cm. The dissection continued into the bifurcation of the aorta and involved the left common iliac artery. Because of the patient's vascular anomalies, the cardiothoracic surgeon requested that the patient be transferred to a tertiary care center by helicopter. At the tertiary care center, the patient underwent surgery and the aortic arch was replaced. At 6-month follow-up, the patient was still receiving metoprolol (increased to 50 mg daily) for blood pressure control. He was active with minimal discomfort.