A 65-YEAR-OLD man had a 1-week history of midepigastric pain, nausea, and vomiting. He denied any previous abdominal complaints. His medical history was significant for peripheral vascular disease, hypertension, a 2-pack-per-day smoking habit, and alcohol abuse (12 drinks per day). His physical examination was remarkable for an irregular heart rate of 124 beats/min, temperature of 38.4°C, and mild abdominal distention and tenderness, but no signs of peritonitis. His white blood cell count was 20.1 × 103µL and his sodium level was 119 mEq/L. Plain abdominal x-ray films were nonspecific.