Fukuda Ikuo, Daitoku Kazuyuki, Minakawa Masahito, Fukuda Wakako
Department of Thoracic and Cardiovascular Surgery, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hrosaki, Aomori 036-8562, Japan.
Gen Thorac Cardiovasc Surg. 2013 Jun;61(6):301-13. doi: 10.1007/s11748-013-0203-y. Epub 2013 Feb 13.
Atheroembolism is an emerging problem in cardiovascular surgery, especially in elderly patients. Severe atherosclerosis of the thoracic aorta usually reflects systemic atherosclerosis. Aggressive preoperative and intraoperative evaluation of the aorta using enhanced CT, transesophageal echocardiography and epiaortic ultrasound is important in elderly patients as well as those with systemic atherosclerosis. To prevent atheroembolism, it is important to select an adequate arterial perfusion site and to avoid touching the diseased aorta until circulatory arrest. In atherosclerotic aortic arch aneurysm, central cannulation under ultrasound guidance and directing the dispersive cannula toward the aortic root is a simple and effective perfusion strategy. Axillary perfusion is useful as an alternative to central cannulation in atherosclerotic aortic disease, but special care is necessary to avoid complications when the patient has a small axillary artery or flail atheroma around the arch vessels. In femoral artery perfusion, retrograde perfusion may induce paradoxical cerebral embolism, but the incidence of stroke is comparable with axillary perfusion when there is adequate preoperative screening using transesophageal echography. Circulatory arrest with/without cerebral perfusion is another important strategy when the aorta has severe atherosclerosis. Recent literature has shown that mild hypothermia may be safe for anterior cerebral perfusion during circulatory arrest, but optimal flow rates and time limitations are unknown. A simple calcified aorta called "porcelain aorta" may be managed by circulatory arrest, local debridement and the clamp method. Several surgical options are proposed for this clinical entity but their use will diminish in the future because of transcatheter valve replacement.
动脉粥样硬化栓塞是心血管外科中一个新出现的问题,尤其是在老年患者中。胸主动脉的严重动脉粥样硬化通常反映了全身动脉粥样硬化。对于老年患者以及患有全身动脉粥样硬化的患者,使用增强CT、经食管超声心动图和主动脉外膜超声对主动脉进行积极的术前和术中评估很重要。为预防动脉粥样硬化栓塞,选择合适的动脉灌注部位并在循环停止前避免触碰病变主动脉很重要。在动脉粥样硬化性主动脉弓瘤中,在超声引导下进行中心插管并将分散插管指向主动脉根部是一种简单有效的灌注策略。在动脉粥样硬化性主动脉疾病中,腋动脉灌注可作为中心插管的替代方法,但当患者腋动脉细小或主动脉弓血管周围有浮动动脉粥样斑块时,必须特别注意避免并发症。在股动脉灌注中,逆行灌注可能会诱发矛盾性脑栓塞,但当使用经食管超声心动图进行充分的术前筛查时,中风发生率与腋动脉灌注相当。当主动脉有严重动脉粥样硬化时,采用或不采用脑灌注的循环停止是另一项重要策略。最近的文献表明,轻度低温在循环停止期间进行前脑灌注可能是安全的,但最佳流速和时间限制尚不清楚。一种称为“瓷主动脉”的简单钙化主动脉可通过循环停止、局部清创和钳夹法进行处理。针对这一临床实体提出了几种手术选择,但由于经导管瓣膜置换术,它们在未来的应用将会减少。