Aortic dissections and aneurysms Quiz: Ace Your Exams

A 45-year-old woman comes to the emergency department after experiencing several episodes of non-bilious and non-bloody emesis, followed by a sudden onset of intense chest pain radiating to the back. She also notes that she has left arm weakness. The patient states that prior to today, she has been in her usual state of health. She drinks a pint of vodka daily and regularly uses intranasal cocaine. She reports last using cocaine this morning. Her temperature is 37.0 °C (98.6 °F), pulse is 102/min, respirations are 22/min, blood pressure is 210/120 mmHg, and oxygen saturation is 96% on room air. The patient appears disheveled and in significant distress. Physical examination shows 1+ peripheral pulses in the right upper extremity and 2+ pulses in the left upper extremity. Neurological examination shows 3/5 power in the left upper and lower extremities compared to 5/5 power in the right upper and lower extremities. Laboratory markers demonstrate a troponin of 0.7 ng/ml and a WBC of 12,000/mm³ (reference range: 4,500-11,000/mm³). ECG demonstrates ST-depressions in leads II, III, and aVF. Which of the following is the most likely underlying mechanism of this patient’s condition?