Elephant Trunk Prosthesis Kinking: Transesophageal Echocardiography Diagnosis

Abstract

A patient underwent aortic arch replacement by the elephant trunk technique as the first part of treatment of a Stanford type A aortic dissection with retrograde extension into the aortic arch. The aortic arch was approached through a median sternotomy and was replaced because of extended dissection to left subclavian artery. Cardiopulmonary bypass (123 min) and deep hypothermic circulatory arrest at 18°C (34 min) allowed both anastomosis of the elephant trunk and cerebral protection. An intimal tear was clearly identified 50 mm after the origin of left subclavian artery. The proximal end of a 22-mm aortic prosthesis (Polythese, LPI France) was sutured to the ascending aorta 10 mm distal to the sinotubular junction. Then, the innominate and left common carotid arteries were implanted directly onto the graft. The left subclavian artery was transposed onto the left common carotid artery. The length of the inserted prosthesis was 150 mm. A large portion of intimal flap was resected as far as possible into the aorta (leaving at least 1 cm on both sides of the membrane to avoid injury to the aorta) to allow insertion of the distal part of the prosthesis. The final result of the procedure is described on Figure 1. After placement of several clips to facilitate radiologic visualization, the distal end of the prosthesis was introduced and left free in the descending thoracic aorta. A major enlargement of the mediastinum appeared 28 days after surgery on chest radiograph with the upside-down position of metallic clips marking the distal part of the aortic prosthesis. A pressure gradient between the arm and leg was then noted (125/65 and 85/45, respectively) 28 days after surgery. Our patient’s clinical examination was normal and there was no sign of organ failure. A transesophageal echocardiography (TEE) examination was then performed showing on a descending aorta short-axis view (desc aorta SAX) a double-lumen aspect of the distal part of the prosthesis. A descending aorta long-axis view revealed a complete kinking of the prosthesis with the distal end in cephalad direction (Fig. 2). A high velocity (yellow) and turbulent color Doppler flow pattern (mosaic) was noted at the kinking level and at the distal end of the prosthesis (please see video loop at www.anesthesia-analgesia.org). Further TEE examination showed that the prosthesis was positioned inside the false lumen without intimal membrane in the initial part of descending aorta. Swirling echo reflections indicative of low flow were noted in the false lumen. Complete examination of the descending aorta revealed that the intimal membrane was preserved in the distal part of the aneurysm with false This article has supplementary material on the Web site: www.anesthesia-analgesia.org.