Stenosis of a novel frozen elephant trunk in a patient with chronic dissection.

A partial elephant trunk (PET), a new type of frozen elephant trunk, was designed to prevent distal stent graft-induced new entry using a thinner nitinol wire with less radial force. We report a case of PET stenosis in chronic dissection. Total arch replacement was performed using a PET. After weaning from cardiopulmonary bypass, the lower-limb blood pressure decreased to 90% of the upper-limb blood pressure. Intraoperative transesophageal echocardiography revealed incomplete PET expansion, and on postoperative day 1, the lower-to-upper body blood pressure ratio further decreased to 70% due to PET stenosis at the steeply angulated arch. Emergency thoracic endovascular aortic repair was successfully performed, completely resolving the pressure gradient.