冠心病患者行腹主动脉瘤修补术是安全的

Safe AAA Repair Possible Despite Presence of CAD      

（北京武警总医院 韩玮 翻译）

加利福尼亚斯坦福大学医疗中心的血管外科主任Christopher K. Zarins指出尽管某些患者并存有严重的冠状动脉疾病，腹主动脉瘤外科修补或腔内治疗仍是安全的。Zarins说，“稳定冠心病可以药物治疗，不稳定急性的冠心病应在腹主动脉瘤术前进行治疗，对于那些有急性腹主动脉瘤症状或破裂的患者，无论冠心病状况如何都应该治疗腹主动脉瘤。”

动脉瘤破裂的危险主要和瘤体体积有关，外科手术死亡的风险和破裂的风险是治疗选择的重要因素。“瘤体越大，破裂的风险越大，因此要对患者的风险进行评估并做出治疗选择。”

治疗方法

首先要用多普勒和CT 来评价瘤体直径，并确定患者是否适合行腔内修补，然后作术前的心脏状况评估，包括病史和体检、多巴酚丁胺超声心动图，治疗应由瘤体大小来决定，目前的指南建议瘤体直径大于5cm 就应该进行治疗，但并不是说该标准适用于所有患者。

治疗方法的选择

当确定腔内修补或开胸手术时应衡量心脏和其他的危险因素，开胸手术修补预防动脉瘤破裂方面更有效，死亡率5%，在过去30－40年中一直如此。腔内修补适合于解剖合适的病人，如果解剖不合适则需要开胸手术。1999年FDA批准了首例血管内修补器械，目前有五种支架上市。腔内修补能降低的死亡率和致残率，恢复更快。

Zarins说“该技术发展之迅猛令人吃惊，最终将改变动脉瘤治疗的蓝图”。

一些前瞻性随机试验比如EVAR-1HE DREAM 显示腔内修补的手术死亡率比外科手术降低三倍（1.5％vs 5％），该益处可以维持到四年。

冠心病的处理

合并不稳定冠心病或左主干病变的腹主动脉瘤病例需要术前再血管化，术前再血管化可以考虑置入裸支架或CABG。而稳定性冠心病的腹主动脉瘤患者从再血管化治疗中获益不大，前瞻性多中心试验显示围手术期再血管化并不能改善生存，也不能降低手术后MI、死亡率或住院时间，而且如果进行冠脉再血管化，将不得不推迟动脉瘤手术时间的，不见得是个好事。

对于非左主干的稳定冠心病患者，优化药物治疗尤其是大剂量beta阻滞剂能降低死亡率和MI.。

最后Zarins指出动脉瘤的治疗需要血管外科医生、介入医生和心内科医生的通力合作，才能将危险性降低到最低。

（来源：www.tctmd.com）

Safe AAA Repair Possible Despite Presence of CAD      
 
Key Points:

Careful management and selection of endovascular vs. open repair important to success.

By TCT Daily Staff

Abdominal aortic aneurysms can be repaired safely using endovascular or open repair in almost all patients, despite the presence of co-existing severe coronary artery disease, said  Christopher K. Zarins, MD, chief of vascular surgery at Stanford University Medical Center, California.

"Stable CAD can be managed medically, and unstable, acutely symptomatic CAD should be treated before elective abdominal aortic aneurysms," Zarins said Tuesday.

"In case of acute abdominal aortic aneurysm symptoms or rupture, proceed with aneurysm treatment regardless of the coronary situation," he said.

The risk of aneurysm rupture is primarily related to size issues and the risk of death from surgery, which are the factors that guide the selection of treatment options for patients.

"The bigger the aneurysm, the bigger the risk of rupture, so it is important to know about the aneurysm in terms of putting the risk perspectives into play and knowing what your treatment decision will be," he said.

Treatment approach

Approach to treatment should consist of evaluating the patient with Duplex and/or CT scan to assess aortic diameters and to determine if the patient is anatomically suitable for endovascular repair, Zarins said. Then a pre-operative cardiac evaluation, consisting of a clinical history and exam and dobutamine stress echocardiography should be conducted. Treatment selection should be determined by aneurysm size, he said. Current guidelines suggest treatment if the aneurysm is >5.5 cm, however, one size may not be standard for all patients.

Method selection

When deciding to use endovascular repair or open repair, consider cardiac risk and other risk factors, Zarins said.

Open surgical repair is effective in preventing aneurysm rupture, he said, and it has a mortality rate of 5%, which has not changed in the last 30 to 40 years.

Endovascular repair is the procedure of choice for patients with favorable anatomy, while open repair is preferable if the patient has unsuitable anatomy. The FDA approved the first endovascular repair device in 1999; there are now five such devices on the market and use of the method is increasing (see Figure). Endovascular repair is associated with reduced morbidity and mortality and faster recovery, Zarins said.

"What’s amazing is how rapidly this technology has been adopted and incorporated into practice. It really has changed the landscape of how we approach aneurysms," he said.

Results from prospective, randomized trials, such as EVAR-1 and DREAM, have shown a threefold reduction of operative mortality with endovascular repair vs. surgery (1.5% vs. 5%, respectively). Benefits were sustained out to four years.

CAD management

Management of patients with abdominal aortic aneurysm and unstable CAD or left main disease may require pre-operative revascularization, according to Zarins. Bare metal stenting or CABG should be considered in patients undergoing pre-operative coronary revascularization that have a semi-urgent need for vascular surgery.

Overall, patients with stable CAD should proceed with abdominal aortic aneurysm repair since they do not benefit from pre-operative coronary revascularization, according to Zarins. Results from prospective, multicenter trials show that pre-operative coronary revascularization does not improve survival and does not lead to a reduction in postoperative MI, mortality or length of hospital stay in these patients.

"If you do undertake pre-operative coronary revascularization, you may delay the vascular surgery by a month or more, and this, of course, is not a good thing," he said.

In patients with stable CAD but no left main disease, optimal medical therapy with high-dose peri-operative beta-blockers will help to minimize the risk of mortality and MI, Zarins said.

Finally, communication is needed between the vascular, interventional and cardiology teams in all areas of patient care to help reduce risk factors, he said.

Disclosures:

Dr. Zarins reports no relevant conflicts of interest.

（source：www.tctmd.com）