The Application Of The Stented Elephant Trunk Procedure In Patients With Stanford Type B Aortic Dissection

With the development of people's living standard, the cardiovascular disease is the key reason of death in the developing countries. Aortic dissection, especially acute aortic dissection, is a serious cardiovascular disease associated with high morbidity and mortality. It could lead to death because of acute left heart failure, acute myocardial infarction, cerebral incidence, acute renal failure, cervical organ ischemia involved with intimal tear, and acute pericardial effusion/tamponade or hemorrhagic shock due to aortic rupture. The emergency surgical treatment was required to be performed in patients with Stanford type A aortic dissection with consensus. However, the optimal mode of treatment strategy for the patients with Stanford type B aortic dissection remains some controversial presently. Aggressive medical therapy was the preferred method for the only uncomplicated patients and operative intervention was indicated if there was life threatening situations such as sign of aortic rupture (pleural effusion and hemorrhagic shock), being prone to aortic rupture (uncontrollable hypertension, refractory pain and progressive decrease of aortic diameter) and cervical organ or limb malperfusion in the patients with acute or chronic type B aortic dissection. Despite the improvements made with regard to surgical treatment, CPB technique and the nursing level of the perioperative stage, the mortality was 29% with its poor outcome. The situations such as false lumen dilation, false lumen rupture and the end-organ malperfusion might have a great influence on the operative results in patients with Stanford type B aortic dissection. Endovascualr stent graft treatment with low morbidity and mortality may be an alternative to open surgery. Some patients with type B dissection received endovascualr treatment with stented graft to cover the primary intimal tear and obliterate the false lumen, and then acquired satisfactory results. However, endovascualr stent graft placement was not suitable to the patients while there was no precise targeting of the stent landing zone and the open surgery was mandatory for these patients. Appropriate extent resection of descending aorta was confronted with surgeon and palliative procedure was performed to avoid severe complication. Limited resection of descending thoracic aorta and reconstitution of aortic layers distally by means of suture of the dissected septum to the adventitial were performed or blood flow was restored in both the true and the false channels in some time. False lumen remained patent and dilated progressively in most patients. Moreover, the patency of false lumen was a strong independence risk factor of dissected-related morbidity and mortality. With the improvement of elephant trunk, the stented elephant trunk was applicable to the patients with aortic dissection and aortic aneurysm. The elephant trunk procedure was useful for the patients with aortic dissection to promote obliteration of false lumen with thrombus formation, reverse organ malperfusion and avoid reoperation in the future. We performed the stented elephant trunk procedure for the patients with Stanford type B aortic dissection. The subtype of aortic dissection is much useful in determining the optimal procedure, operative indication and plan, estimating the prognosis.This report describes the application of stented elephant trunk in patients with Stanford type B aortic dissection according to the subtype of aortic dissection. The experience of proximal descending thoracic aortic replacement associated with short stented elephant trunk implantation for acute simple Stanford type B aortic dissection was reported in the first part. A total of 9 pateints with acute Stanford type B aortic dissection underwent this procedure. There was no death in this group. And spinal cord injuries occurred in 2 patients. One patient with paresis recovered fully during the follow-up. No other complication observed. Proximal descending thoracic aorta replacement associated with short stented elephant trunk implantation was a fine surgical procedure for the patients with acute simple type B dissection who were unsuitable for endovascualr stent graft placement. Proximal descending thoracic aortic replacement associated with short stented elephant trunk implantation for patients with chronic Stanford type B aortic dissection was reported in the second part. There was no death and severe complication in these patients. The stented elepahnat trunk procedure could not result in the spinal cord injury and organ malperfusion in patients with chronic Stanford type B aortic dissection. Otherwise, it could reverse the organ malperfusion with this procedure. Total aortic arch replacement associated with stented elephant trunk procedure for patients with complex Stanford type B aortic dissection was reported in the third part. There were 2 deaths in patients with total aortic arch replacement associated with elephant trunk procedure under off-pump. 2 patients underwent thoracoabdomianl aortic replacement during the second-staged operation. And there was no other complication. This procedure was benefit to patients with complex Stanford type B aortic dissection due to management of both proximal arch and distal arch lesions at one-staged, avoidance of false lumen dilation, reverse organ malperfusion, avoidance of retrograde dissection and simplied second staged operation. Total aortic arch replacement associated with stented elephant trunk procedure for patients with simple Stanford type B aortic dissection was reported in the fourth part. It could manage simple Stanford type B aortic dissection associated with aortic root, ascending aorta lesions at one-staged and promote obliteration of false lumen with thrombus formation, reverse organ malperfusion and avoid reoperation with this procedure. Finally, we analyzed the data of patients with type B dissection who received stented elephant trunk implantation and summarized our experience.