There are at least 7000 aortic dissections diagnosed in the United States each year. Type B dissections accounted for 38% of cases enrolled in the prospective International Registry of Aortic Dissection. We report a case of a 48-year-old hypertensive woman with an acute type B aortic dissection causing significant dynamic obstruction of the aorta. Intravascular ultrasound of her aorta revealed a mobile intimal flap nearly obliterating the true lumen with each systolic contraction. Simultaneous pressure tracings obtained from her ascending aorta and femoral artery demonstrated a systolic pressure gradient in excess of 100 mm Hg. The patient developed progressive renal failure and ultimately underwent successful operative replacement of the proximal descending thoracic aorta with a Dacron graft. In this case presentation, we highlight the unusual physiology exemplified by this case and explore contemporary management strategies for complicated type B aortic dissection, including surgery and catheter-based techniques.