Falkenberg M, Lönn L, Schroeder T, Delle M
Department of Radiology, Sahlgrenska University Hospital, Gothenburg, Sweden.
J Cardiovasc Surg (Torino). 2010 Apr;51(2):177-82.
Thoracic endovascular aortic repair (TEVAR) is the treatment of choice for descending thoracic aortic aneurysms (TAA). However, not all patients with TAA can be treated with the endovascular technique. Insufficient proximal and/or distal sealing zone is the most common reason for open surgery in these patients. If the distal sealing zone above the celiac axis is too short, several endovascular alternatives are possible; hybrid procedures with TEVAR and open by-pass to the celiac artery, custom made stent-grafts with scallop or fenestration for the celiac artery, or intentional coverage of the celiac artery. In the latter case, adequate collateral supply to the upper gastrointestinal tract is crucial. Collateral arteries joining the celiac and the superior mesenteric arteries are well characterized in patients with chronic celiac stenosis or occlusion. Are these collateral pathways sufficient also for sudden iatrogenic closure of the celiac artery? By performing a preoperative angiography of the superior mesenteric artery with temporary balloon occlusion of the celiac artery, collateral capacity between the two vessels can be tested in advance. Exact positioning of the distal end of a large thoracic stent-graft can be challenging and require special considerations and techniques. Most case series in the literature support the efficacy and the safety of intentional celiac covering. However, there are also reports of ischemic foregut complications that could be associated to the procedure. Taken together, in the large majority of patients, it appears that intentional celiac coverage can be done safely provided that sufficient collateral function have been demonstrated in advance.
胸主动脉腔内修复术(TEVAR)是降主动脉瘤(TAA)的首选治疗方法。然而,并非所有TAA患者都能采用血管内技术治疗。近端和/或远端密封区不足是这些患者进行开放手术的最常见原因。如果腹腔干轴上方的远端密封区过短,则有几种血管内替代方案可行;采用TEVAR与腹腔动脉开放旁路的杂交手术、为腹腔动脉定制带扇形或开窗的支架移植物,或有意覆盖腹腔动脉。在后一种情况下,为上消化道提供充足的侧支血供至关重要。在慢性腹腔干狭窄或闭塞患者中,连接腹腔干和肠系膜上动脉的侧支动脉已得到充分描述。这些侧支通路对于腹腔动脉突然医源性闭塞也足够吗?通过在临时球囊闭塞腹腔动脉的情况下对肠系膜上动脉进行术前血管造影,可以提前测试这两条血管之间的侧支能力。大型胸段支架移植物远端的精确定位可能具有挑战性,需要特殊的考虑和技术。文献中的大多数病例系列都支持有意覆盖腹腔动脉的有效性和安全性。然而,也有缺血性前肠并发症的报道,这些并发症可能与该手术有关。综上所述,在绝大多数患者中,只要提前证明有足够的侧支功能,似乎可以安全地进行有意的腹腔动脉覆盖。