Surgical Repair of Retrograde Type A Aortic Dissection after Thoracic Endovascular Aortic Repair
A 75-year-old man visited our emergency department complaining of cough and sputum lasting one month. There was no definite mediastinal widening on a simple chest X-ray, but a prominent aortic arch was observed in comparison to the past two years. A three-dimensional computed tomography scan revealed multiple aneurysmal dilatations with pseudoaneurysm and thrombi in the aortic arch and proximal abdominal aorta. They were measured to be 2.7×1.1 cm (external diameter: 5.1 cm) and 1.5×3.6 cm, respectively, in size. Another focal aneurysmal dilatation was observed in the distal abdominal aorta just above the iliac bifurcation (). Upon admission, transthoracic echocardiography showed moderate aortic regurgitation and minimal mitral regurgitation without regional wall motion abnormalities. We planned a staged operation (thoracic endovascular aortic repair for aortic arch aneurysm first and aortic valve replacement later) as the patient was considerably old and had poor pulmonary function.\nThoracic endovascular aortic repair (36×100 mm, SEAL thoracic limb stent graft; S&G Biotech, Seongnam, Korea) was performed as previously described []. There was a 12-mm-long landing zone between the left subclavian artery and aortic arch aneurysm with an aortic diameter of 30 mm. Considering the possible type Ib endoleak caused by the mild aneurysmal dilatation of the descending thoracic aorta, we planned to position two overlapping stent grafts strategically (one just distal to the left subclavian artery, and the other covering the descending thoracic aorta). Balloon angioplasty was not performed. The patient was monitored in the intensive care unit postoperatively, transferred to the general ward on the first postoperative day, and discharged on the fifth day without any specific symptoms or signs. No endoleaks were found on the computed tomogram on the second day (). The patient follow-ups in the outpatient department revealed no symptoms except for the retrograde type A aortic dissection observed on the three-month computed tomogram performed as a routine follow-up study ().\nThe patient underwent aortic valve replacement and ascending aorta replacement under deep hypothermic circulatory arrest and selective unilateral antegrade cerebral perfusion. The aortic valve was replaced with a Carpentier-Edwards no 23. tissue valve (Edwards Lifesciences, Irvine, CA, USA). The intimal tear had originated from the bare metal structure in the anterior direction, which was in contact with the anterior wall of the ascending aorta. This bare metal structure was partially exposed after the excision of the dissected aorta. Distal aortic anastomosis was performed without the removal of the stent graft and reinforced circumferentially with pledgeted sutures. Distal aortic anastomosis sutures partly included the proximal bare metal structure of the stent graft. The pump time, aortic cross clamp time, circulatory arrest time, and selective antegrade cerebral perfusion time were 234, 144, 40, and 32 minutes, respectively.\nThe patient was extubated on the first postoperative day, transferred to the general ward on the third postoperative day, discharged on the eighteenth day, and followed up for 24 months without specific symptoms. Endoleaks were observed in the junction of the distal anastomosis site and the bare metal structure of the stent graft on the computed tomogram on the seventh day, but had no significant interval changes on the computed tomogram after 20 months ().