Review Question - QID 214875

A 67-year-old man presents to the emergency department bleeding from his nose and coughing up blood. It started yesterday intermittently and is now persistent and more severe. The patient has a medical history of diabetes, hypertension, atrial fibrillation, and alcohol use disorder. His daily medications include metformin, lisinopril, and warfarin. His temperature is 98.7°F (37.1°C), blood pressure is 164/88 mmHg, pulse is 113/min, respirations are 15/min, and oxygen saturation is 96% on room air. Physical exam reveals active epistaxis in both nares, obscuring a thorough physical exam. The patient has 2 episodes of hematemesis while in the emergency department. Laboratory results are listed below.

Serum:
Na+: 140 mEq/L
Cl-: 101 mEq/L
K+: 4.0 mEq/L
HCO3-: 25 mEq/L
BUN: 40 mg/dL
Creatinine: 1.3 mg/dL
INR: 7.0

The patient is given factor replacement therapy and bilateral nasal packing is placed, which appears to resolve the bleeding. Several minutes later, the patient vomits a large amount of bright red blood mixed with what appears to be coffee grounds. His packing is removed, and a deluge of blood leaks from the nares. The patient is subsequently intubated. Which of the following is the most likely cause of this patient’s bleeding?