Aortic Dissection (Stanford Type A)

A 58-year-old man with poorly controlled hypertension and significant smoking history presents with sudden-onset tearing chest pain radiating to the back, diaphoresis, and dyspnea. On examination, blood pressure is 200/110 mmHg in the right arm and 140/90 mmHg in the left arm, with a new diastolic murmur. CT angiography of the aorta demonstrates an intimal flap separating the true and false lumens extending from the ascending aorta through the arch to the iliac bifurcation. The structure marked **C** in the diagram shows partial thrombosis. Which of the following best describes the pathophysiological consequence of the structure marked **C** in this Stanford Type A aortic dissection?