PLE-8313

PLE-8313

A 67-year-old woman is brought to the emergency department because of severe chest pain. She experienced the pain 4 hours after undergoing outpatient endoscopy and dilatation of an esophageal stricture caused by reflux. At discharge, she reported no chest pain. However, three hours later, she vomited a small amount of blood and experienced severe pain. Upon examination, she appears pale and has a temperature of 38 C (100.4 F), blood pressure of 140/85 mm Hg, pulse rate of 125/min, and respiratory rate of 22/min. Crepitus is observed in the neck and moderate epigastric tenderness is present. The lungs are clear upon auscultation and breath sounds are equal bilaterally. Rectal examination reveals no masses and a test of the stool for occult blood is positive. The most likely cause of these symptoms is: