Journal of Cardiac Surgery | 2021
Reply: Surgical repair of thoracoabdominal aortic aneurysm accompanied by Leriche syndrome using a quadrifurcated graft without a distal anastomosis
Abstract
To the Editor, We appreciate the valuable comments on our article by Didem Melis Ozatas et al. As you mentioned, the internal thoracic arteries (ITAs) could become the major blood supplies to the lower extremities in case of Leriche syndrome. Our preoperative angiography demonstrated a huge right ITA which supplied abundant blood to the right leg. We should not use it as a graft without surgical revascularization to the right leg. On the other hand, the left ITA was smaller than the right one, and it supplied less blood to the left leg compared to the right ITA. Visceral arteries provided rich collateral blood flow to the left leg. We speculate the reason why the left ITA was not dilated so much compared to the right was that blood supply to the left leg was mainly provided from the visceral arteries via collateral. During the coronary artery bypass grafting (CABG), the left ITA was 4mm in its diameter at most, and anastomosis site was 3mm. There was no evidence of atherosclerosis in the graft. Left anterior descending artery was about 2mm. There was discrepancy between the ITA and coronary artery, however, this condition was frequently observed with saphenous vein graft. At 8 years after CABG, the grafts were confirmed patent by contrastâenhanced computed tomography and at 9 years, the patient has no chest symptoms. We believe that the graft quality would be preserved as long as it is not dilated morbidly. Revascularization to the left leg at the time of CABG was a therapeutic option, including ascending aorta or axillary artery to the femoral artery. However, because of an emergent situation, history of unknown surgery to the left leg, and no information of the left femoral artery, we did not add surgical procedures to the left leg. After the emergent CABG, we checked his femoral arteries, and found that the left common artery was very small with its diameter of 4 mm at most. We proposed surgical revascularization to the lower extremities, however, the patient preferred to medical and physical therapy including smoking cessation. His leg symptom improved and we decided not to provide surgical revascularization. In the thoracoabdominal surgery, side clamp to the proximal descending aorta without cardiopulmonary bypass is an effective method in certain cases. However, this method leaves the aortic stump at the end, which might cause another aneurysmal formation in the future. We do not think it a good idea to leave aortic stump in the case of Leriche syndrome. Our aim to use the prosthetic quadrifurcated graft is to prevent aneurysm or thrombus formation by eliminating aortic stump or graft stump. In the present case, the thoracoabdominal aortic aneurysm contained significant amount of thromboses. Nevertheless, the aneurysmal size increased as time went on. Glue injection is useful especially type II endoleak after endovascular aortic aneurysm repair. I am skeptical whether it is effective in the stump aneurysm where aortic pressure comes directly. Because his left kidney was atrophic and very small, we needed to reconstruct the right renal artery perfectly. As cardiopulmonary bypass might associate with side effects, we chose it to obtain good exposure and secure reconstruction especially at the right renal artery. Concerning the reconstruction of intercostal arteries, we did not reconstruct any of them. Before the thoracoabdominal operation, we detected intercostal arteries at Th6, 7, 9, and 10 as well as L3 and L4 by contrastâenhanced computed tomography. During the surgery, we identified intercostal artery at Th10. It was ligated because it was much smaller than we expected and difficult to reconstruct. As our figures showed, intercostal artery at Th9 was relatively large. As long as we preserve Th9 artery and collaterals from the visceral arteries, neurological complication was less likely. In case of aortic aneurysm with Leriche syndrome, when there are enough size of terminal abdominal aorta, iliac, or femoral arteries, traditional graft replacement is feasible. However, in case of aortic aneurysm with Leriche syndrome without enough size of distal arteries, we believe that the quadrifurcated graft could be a therapeutic option.