Case
A 50-year-old woman presented with shortness of breath on exertion. She had undergone total aortic arch replacement for Stanford type A aortic dissection 17 years previously. She had been taking prednisolone (7.5 mg) for SLE since she was 18 years old. Transthoracic echocardiography showed left ventricular diastolic and systolic diameters of 52 and 41 mm, respectively, left ventricular ejection fraction of 42.5%, and mild aortic regurgitation. Echocardiography revealed a large ascending aortic aneurysm compressing the right atrium. Computed tomography showed the 63-mm ascending aorta near the proximal anastomosis site compressing the superior vena cava and right atrium (Fig. 1) and a 53-mm thoracoabdominal aneurysm (TAA) and a 38-mm abdominal aortic aneurysm (AAA). Cardiac catheterization showed chronic total occlusion of the left anterior descending (LAD) branch. The patient underwent urgent surgery for ascending aortic aneurysm and LAD occlusion.
Cardiopulmonary bypass (CPB) was initiated via right axillary and right femoral artery perfusion, with inferior vena cava drainage through the right femoral vein. Superior vena cava drainage was performed via median sternotomy and CPB was established. The harvested great saphenous vein was anastomosed to the LAD during systemic cooling to a bladder temperature of 23°C. After circulatory arrest, the aneurysmal aortic wall was incised. The artificial blood distal to the aneurysm was clamped and circulation was resumed. Cardioplegic solution was infused from the coronary ostium and anastomosed graft to achieve cardiac arrest. Ascending aortic replacement was performed using a 24-mm J-graft (Japan Lifeline Co., Ltd., Tokyo, Japan). Proximal anastomosis was performed at the sinotubular junction level. The saphenous vein graft was anastomosed to the J-graft and the aorta was declamped. A 5-mm hole on the right atrium that had been adherent to the aneurysm was found and directly closed. The CPB weaning was uneventful and the duration of surgery, CPB, cardiac arrest, and circulatory arrest were 494, 229, 113, and 3 mins, respectively. There was no recurrence of ascending aortic aneurysm 2 years postoperatively.
Microscopic examination revealed that the aneurysm was true because the aneurysmal wall was composed of all three layers including tunica intima, media, and externa and showed severe atherosclerotic changes. The tunica intima thickened with the formation of atheroma. The smooth muscles of tunica media decreased, and the elastic fibers were disordered. Some elastic fibers ruptured, and fragmented fibers were observed in the tunica media. (Fig. 2a, b).