Anesthetic management for distal aortic arch aneurysm stent grafting

A 76-year-old woman with thoracic aortic aneurysm involving distal aortic arch was scheduled for graft replacement from ascending to proximal aortic arch with endovascular stent graft to descending aorta. Surgical procedures were performed under median sternotomy with hypothermic systemic circulation arrest and selective cerebral perfusion. The stent graft composed of 30 mm Gianturco Z stent and 27.5 mm woven Dacron graft was introduced into the descending aorta under the guidance of transesophageal echocardiography (TEE) and fluoroscopy. Ascending and proximal aortic arch replacement was then performed with four branched woven Dacron graft. The aortic pathology was confirmed by TEE and the extent of the aneurysmal lesion was defined. TEE was also useful to find the dislodgement of the stent graft after deployment. This surgical technique, being less invasive than conventional thoracotomy, would be indicated for elderly patients with distal aortic arch aneurysm. TEE is the vital imaging technique for placement of the stent graft, as well as for intraoperative cardiac monitoring.     

Endovascular treatment of descending thoracic aortic aneurysms and dissections.

Various endovascular techniques have become viable therapeutic alternatives in the treatment of patients with many types of descending thoracic aortic pathology and aortic dissections. Descending thoracic aortic aneurysms can be successfully treated using stent grafts. This technique is less invasive and is associated with acceptable morbidity and mortality rates. Patients who are particularly likely to benefit include the very elderly population; those with markedly compromised cardiac, pulmonary, or renal status; and individuals who have previously undergone complex operations on the thoracic aorta. Other endovascular methods, such as aortic flap fenestration, stent, or covering of the primary intimal tear in the descending thoracic aorta with a stent graft, have also been effectively employed in the treatment of peripheral arterial complications of aortic dissection. Despite the reported early success of these endovascular percutaneous methods, true assessment of the effectiveness of these various techniques awaits long-term follow-up evaluation in large patient populations.     

The importance of intraoperative transesophageal echocardiography in endovascular repair of thoracic aortic aneurysms

Endovascular repair of the aorta (EVAR) is a promising alternative to open repair. Transesophageal echocardiography (TEE) is a sensitive imaging modality for aortic disease. We reviewed our experience with TEE in thoracic EVAR. Seven patients underwent thoracic EVAR under general anesthesia. Intraoperative angiography and TEE were used to identify the extent of the aneurysm and guide placement of the stent. Doppler color flow was used to supplement angiography to detect flow within the aneurysmal sac after stent placement. The endograft was successfully deployed in six patients. Endoleak was identified by TEE in three patients and confirmed by angiography in two of them. EVAR was abandoned in one patient on the basis of TEE findings of extensive aortic dissection. We found TEE to be a valuable intraoperative tool for 1) identifying aortic pathology, 2) confirming that the guidewire is in the true lumen, 3) aiding stent graft positioning, and 4) supplementing angiography for detecting endoleaks. TEE can supplement information obtained by angiography to enhance the accuracy of EVAR and potentially improve outcomes. The anesthesiologist is ideally positioned to provide the endovascular team with vital information regarding stent positioning, endoleaks, and cardiac performance with a single imaging modality. IMPLICATIONS: Endovascular repair is an emerging alternative to open surgery for aortic aneurysms. We found transesophageal echocardiography to be a valuable imaging tool for guiding placement of the endograft, detecting leaks around the endograft, and supplementing information derived from angiography during endograft deployment.     

Combined open and endovascular repair of a syphilitic aortic aneurysm

The use of endovascular stent grafts in the repair of thoracic aortic aneurysms has provided an alternative means of treatment, particularly in the high-risk patient who may not tolerate conventional open repair. The combination of conventional surgery and endovascular repair may allow for successful treatment in patients with anatomy unsuitable for repair entirely by endovascular means alone. We present the case of a patient with a syphilitic thoracic aortic aneurysm involving the aortic arch and descending thoracic aorta. He underwent a staged repair with an elephant trunk reconstruction of the aortic arch followed by endovascular repair of the descending thoracic aorta. This is the first reported case of the repair of a syphilitic aneurysm by means of endovascular techniques.     

Der Chimney-Graft

A thoracic chimney graft is a stent or stent graft that is deployed in a supraaortic branch vessel, protruding somewhat proximally into the free aortic lumen like a chimney parallel to the main aortic stent graft. The chimney graft is used to preserve flow to vital aortic side branches covered by the main aortic stent graft. Standard off-the-shelf stent grafts can be used to instantly treat lesions with inadequate fixation zones. The chimney graft offers an alternative to fenestrated stent grafts in urgent cases, in aneurysms with challenging neck anatomy, and in thoracic endovascular aortic repair for reconstituting an unintentionally covered aortic side branch. We describe our experience with this technique and review the current literature. More data and further technical improvements are necessary before the chimney graft can be widely advocated.     

经食管超声心动图在胸主动脉瘤介入治疗中的应用

血管内修复术创伤性小，可应用于治疗多种主动脉疾病，如动脉瘤和主动脉夹层。经食管超声心动图(TEE)对主动脉疾病很敏感。术前可通过TEE找到撕裂的内膜片、发现内膜破口、区分类型、区分真假腔及了解心脏状况。术中TEE用于引导导管插至正确位置、观察支架放置过程、监测心功能和室壁运动状况、评价手术疗效。术后随诊通过TEE观察支架内血流情况、检出并发症如内漏等。     

采用胸分支型主动脉支架人工血管对主动脉弓降部夹层行腔内修复治疗

目的探讨采用胸分支型主动脉支架人工血管治疗累及左锁骨下动脉的主动脉弓降部夹层的临床效果。方法自2004年2月至2004年6月,采用血管腔内胸分支型主动脉支架人工血管治疗主动脉弓部夹层14例。14例均为StanforB型主动脉夹层,原发破裂口距左锁骨下动脉开口2～13mm,平均8．7mm。分支型支架由主动脉段支架和分支段支架组成,支架直径较相应支撑部位动脉直径大15％～20％。治疗在血管造影室进行,应用定位导丝、在透视下将分支型主动脉支架人工血管送人并连续释置入主动脉弓和左锁骨下动脉。结果支架释放全部成功。14例患者共放置14只分支型主动脉支架和2只可弯曲型支架人工血管,封闭夹层破裂口,夹层真腔全部恢复正常直径。无远端动脉并发症发生,无死亡病例。全部患者术后恢复正常活动。结论胸分支型主动脉支架人工血管适合于修复破裂口位于左锁骨下动脉开口旁的主动脉弓部夹层。     

Clinical results of endovascular stent graft repair for fifty cases of thoracic aortic aneurysms

Between February 1995 and December 1997, 50 cases (55 lesions) of thoracic aortic aneurysms including 20 cases of aortic dissections were treated with an endovascular technique using the stent grafts. All patients were treated in the operating room under general anesthesia and the stent grafts were implanted through 18 Fr. or 20 Fr. sheathes via femoral arteries under fluoroscopic guidance. The stent graft was composed of several units of self-expanding stainlesssteel Z stents covered with an ultra-thin polyester fabric. Stent graft deployment was technically successful in 53 of 55 lesions (delivery success rate: 96.4%). Exclusion of the aneurysms and entry closing without endoleak were achieved within two weeks after the operation in 43 of 53 lesions (initial success rate: 81.1%). Endoleak was found in 10 lesions (minor endoleak: 8 and major endoleak: 2 lesions). Two patients died in the periopertive period of delivery failures as injury to external iliac artery and damage to the delivery sheath caused by tortuous and narrow access routes. Endovascular stent graft repair of thoracic aortic aneurysms is minimally invasive operation in comparison with conventional surgical graft replacement with extracorporeal circulation. These early results suggest that the stent graft repair is possibly safe and useful treatment for the patients of thoracic aortic aneurysms especially in high risk patients. However, careful long-term follow-up is necessary to prove the value and the effects of this endovascular treatment and improvement of the stent graft system and technical training of endovascular surgery for operators are required to reduce the delivery failure and to determin the stent graft repair is reliable treatment.     

Emergent endovascular stent grafting for perforated acute type B dissections and ruptured thoracic aortic aneurysms

BACKGROUND: The purpose of our study was to demonstrate the effectiveness of endovascular stent grafts in the treatment of acutely ruptured thoracic aortic aneurysms and type B dissections as an alternative to the conventional surgical approach in an emergency setting. METHODS: From January 2001 to October 2001, we deployed 11 emergent endovascular stent grafts into the thoracic aorta. We treated seven ruptured aortic aneurysms and four acutely perforated type B dissections. Aortic rupture was confirmed preoperatively by spiral computed tomography. In all cases, hemothorax was present. The average interval from onset of symptoms to treatment was 28.5 hours. We used nine Talent and two Excluder stent grafts. RESULTS: Deployment of the stent grafts was successful in nine cases. There were two cases of access failure due to small caliber of iliac arteries, and 1 of these patients died shortly after the procedure was abandoned, At 12 months of follow-up, there were no cases of paraplegia, stent migration, or endoleaks. There was, however, one temporary renal failure, and 2 patients required mechanical ventilation for more than 48 hours. CONCLUSIONS: Our experiences with emergency endovascular stent grafting show that the procedure is technically feasible, with less morbidity and mortality than conventional open surgery, in high-risk patients.     

Usefulness of intraoperative transesophageal echocardiography in stent graft implantation for thoracic descending aorta

BACKGROUND: Stent graft implantation for thoracic descending aorta is a promising alternative to open repair. Transesophageal echocardiography (TEE) is a sensitive imaging modality for aortic disease. We reviewed our experience with TEE in stent graft implantation for thoracic descending aorta. METHOD: Five patients underwent stent graft implantation for thoracic descending aorta under general anesthesia. Intraoperative angiography and TEE were used to identify the extent of the aneurysm and the placement of the stent. RESULTS: TEE showed stent graft configuration and presence of leakage in all cases. In three cases, additional stent graft placement or bypass was performed. CONCLUSIONS: Useful information was obtained by TEE in enhancing the accuracy of stent graft positioning potentially improving outcomes. TEE may facilitate repair by confirming aortic pathology, identifying endograft placement, and assessing the adequacy of aneurysm sack isolation, presence of leakage, as well as dynamic intraoperative cardiac performance.     

The Importance of Imaging Assessment Before Endovascular Repair of Thoracic Aorta

Indications for and experience with placement of endovascular stent grafts in the thoracic aorta are still evolving. Recent advances in imaging technologies have drastically boosted the role of pre-procedural imaging. The accepted diagnostic gold standard, digital subtraction angiography, is now being challenged by the state-of-the-art computed tomography angiography (CTA), magnetic resonance angiography (MRA) and trans-oesophageal echocardiography (TEE). Among these, technological advancements of multidetector computed tomography (MDCT) have propelled it to being the default modality used, optimising the balance between spatial and temporal resolutions and invasiveness. MDCT angiography allows the comprehensive evaluation of thoracic lesions in terms of morphological features and extent, presence of thrombus, relationship with adjacent structures and branches as well as signs of impending or acute rupture, and is routinely used in these settings.In this article, we review the current state-of-the-art radiological imaging for thoracic endovascular aneurysm repair (TEVAR), especially focusing on the role of MDCT angiography. After analysing the technical aspects for optimised imaging protocols for thoracic aortic diseases, we discuss pre-procedural determinants of candidacy, and how to formulate interventional plans based on cross-sectional imaging.     

Endovascular treatment of the descending thoracic aorta.

OBJECTIVES: to report our initial experience with endovascular stent graft repair of a variety of thoracic aortic pathology. DESIGN: retrospective single center study. MATERIAL AND METHODS: between February 2000 and January 2002, endovascular stent graft repair was performed in 26 patients: traumatic aortic isthmus rupture (n=3), Type B dissection (n=11) and descending thoracic aortic aneurysm (n=12). The deployed stent graft systems were AneuRx-Medtronic (n=1), Talent-Medtronic (n=13) and Excluder-Gore (n=12). RESULTS: successful deployment of the stent grafts in the intended position was achieved in all patients. No hospital mortality neither paraplegia were observed. Late, non procedure related, death occurred in four patients (15%). Access artery complications with rupture of the iliac artery occurred in two patients and were managed by iliac-femoral bypass. The left subclavian artery was overstented in seven patients (27%). Only the first patient received a carotido-subclavian bypass. The mean maximal aortic diameter decreased significantly in patients treated for descending thoracic aneurysm. Only one patient had an endoleak type II after 6 months without enlargement of the aneurysm. Complete thrombosis of the thoracic false lumen occurred in all but one patient treated for Type B dissection 6 months postoperatively. Two patients underwent a consecutive stent graft placement, due to a large re-entry tear distal to the first stent graft. CONCLUSIONS: endovascular stent graft repair for Type B dissection, descending thoracic aneurysm and aortic isthmus rupture is a promising less-invasive alternative to surgical repair. Further studies are mandatory to determine its long-term efficacy.     

Endovascular repair of the descending thoracic aorta: evidence for the change in clinical practice

The purpose was to review outcome data following endovascular repair of the descending thoracic aorta from reports published between 1994 and 2004. To accomplish this task, 1,518 patients underwent endovascular repair for thoracic aortic disease; 810 thoracic aortic aneurysms, 500 type B thoracic aortic dissections, and 106 traumatic ruptures. The 30-day mortality rate was 5.5% and 6% for late postoperative deaths. The primary technical success rate was 97%, with only 15 patients requiring open conversion. Neurologic deficits occurred in 29 patients. In total, 118 endoleaks were reported; 29 were restented, and the remainder required surgical intervention. Graft infection occurred in 6 cases, and migrations were detected in 10. The conclusion reached is that endovascular repair of descending thoracic aortic disease is feasible and can be achieved with low rates of perioperative morbidity and mortality. As few long-term data exist on the durability of thoracic stent grafts, lifelong surveillance remains necessary.     

Successful treatment of an infected thoracic endovascular stent graft

A 70-year-old man with a chronic type B aortic dissection was treated with two stent grafts deployed in the descending thoracic aorta. The patient was re-admitted to the hospital at 16 months after thoracic endovascular stent grafting because of a high fever. A blood culture showed sepsis due to a Staphylococcus species. A CT scan showed an increase in the size of the thrombosed false lumen. Complete excision of the infected descending aortic wall and infected stent graft were performed. The descending thoracic aorta was reconstructed using a rifampicin-bonded Dacron graft and omental wrapping. The combination of in situ graft replacement using a rifampicin-bonded graft and omental wrapping is considered an effective treatment for thoracic stent graft infection.     

Endovascular Grafts in the Treatment of Thoracic Aortic Aneurysms and Pseudoaneurysms

The purpose of this study was to describe our experience with balloon and self-expanding endovascular grafts for the management of thoracic aortic lesions. Between February 1997 and June 1998, 20 endovascular grafts were implanted in 14 patients for the treatment of thoracic aortic aneurysms and pseudoaneurysms. Endovascular procedures were performed using one of four different devices: (1) Dacron-covered balloon-expandable Palmaztrade mark stent, (2) balloon-expandable Palmaz stent-PTFE graft prosthesis (BE-PS), (3) self-expanding internally supported Nitinol Dacron prosthesis (Vanguardtrade mark SE-V), and (4) self-expanding externally supported Nitinol PTFE prosthesis (Excludertrade mark SE-E). The results show that endovascular grafting represents a potentially important alternative therapy to open repair of the thoracic aorta. Self-expanding devices were, in our experience, easier to use and more accurately deployed.     

When is safe to cover the left subclavian and celiac arteries. Part II: celiac artery

Endovascular repair of thoracic and thoraco-abdominal aortic aneurysms became apparent as an alternative to open repair. When the distal landing zone proximal to celiac artery is inadequate, a traditional open surgical approach with thoracoabdominal aortic replacement concomitant with visceral and renal bypasses is necessary. Alternatively, either an abdominal hybrid procedure with debranching of the visceral vessels with subsequent thoracic stent graft placement or complete endovascular aneurysm exclusion with branched stent grafts is required. Extending the distal landing zone might be possible by covering the celiac artery origin. In this article, the authors review the anatomy of the celiac artery (SA) and the superior mesenteric artery (SMA) and consequences of CA coverage as scenery for a discussion of the ramifications of CA coverage during endovascular thoracic aortic repair (TEVAR). Summarizing the currently available literature, we will demonstrate the feasibility of covering the celiac artery based on a diagnostic algorism.     

Value of intravascular ultrasound for endovascular stent-graft placement in aortic dissection and aneurysm

BACKGROUND: Endovascular stent-graft placement is a new concept for the treatment of aortic dissection and aneurysm. Intravascular ultrasound (IVUS) with established diagnostic features may be instrumental in guiding endovascular procedures. METHODS: We performed IVUS and digital angiography before, during, and after implantation of 47 stent grafts in 40 patients with Stanford type B dissection (26 patients, 28 stent grafts), thoracic aneurysm (9 patients, 11 stent grafts), and abdominal aneurysm (5 patients, 8 stent grafts). RESULTS: IVUS could clearly identify the aortic anatomy and differentiate between true and false lumen in all cases of dissection. In four patients with type B dissection extending from the thoracic to the abdominal aorta the true lumen was exclusively identified by IVUS, and thus, essential for safe execution of the procedure. In another patient stent-graft placement in the aorta was optimized by covering a second entry detected by IVUS, but undetected by angiography. The site of stent implantation, the true and false lumen, as well as entry and reentry were always identified in both thoracic and abdominal aorta. In comparison with angiography, IVUS information led to additional balloon molding due to incomplete stent apposition in seven cases. CONCLUSIONS: As an adjunctive imaging modality IVUS is likely to improve stent-graft placement in aortic type B dissection, especially in patients with abdominal extension.     

Device related problems of thoracic stent-grafts

The outcome of the endovascular repair of abdominal aortic aneurysms seems to be device related. The presented study evaluated the outcome of endovascular procedure in cases of thoracic aortic pathology according to the implanted thoracic stent graft devices. METHODS: Since November 1999 a variety of thoracic aortic pathologies in 59 patients has been treated endovascularly. The median age of the cohort (53 males, 6 females) was 64 years (rang, 21 to 83). The patients presented the following aortic morphology: aneurysm n = 23, dissections with aneurysm n = 9, dissection without aneurysm n = 9, intramural hematoma n = 2, penetrating ulcers n = 2, transsection n = 8, false aneurysm n = 6. The underlying pathology was: atherosclerotic medial degeneration n = 25, acute dissection (< 14 days) n = 10, chronic dissection (> or = 14 days) n = 10, trauma n = 8, iatrogenic n = 6. Three patients presented the symptoms of aortic pulmonary fistulas; one patient was treated due to traumatic aortic oesophageal fistula. The used stent graft devices included the GORE TAG (n = 35), the Talent device (n = 13), the Cook device (Zenith TX 1: n = 5), and the Endofit device (n = 3). At three cases a home-made device (n = 1) or a combination of different stent grafts was implanted (Talent plus TAG, Talent plus TX1). Totally, 93 stent grafts were primarily implanted. RESULTS: The 30-day mortality was 1 / 59. One patient with acute dissection (Stanford type B) suffered from a per-procedural acute retrograde dissection leading to death in spite of the performed Bentall's procedure. Per-operatively, one patient showed cerebral ischemia, one other patient experienced a transsection of the external iliac artery due to the retraction of the introducer sheath, and another patient showed an extravasation of contrast dye. 24 hours following the endovascular procedure, one patient developed paraplegia without regression in spite of performing a spinal drainage. The passage of the introducer sheath of the primarily chosen device was impossible at three cases, in another three cases type I endoleaks were detectable, a type III endoleak was evident at another patient with formerly implanted multiple stent grafts. SUMMARY AND CONCLUSIONS: The results of the endovascular procedures in treatment of thoracic aortic pathologies demonstrated typically device related problems and unwanted events. Various types of stent grafts, introducer sheaths, and delivery systems may be necessary to satisfy the different requirements for different indications.     

Left subclavian artery management in endovascular repair of thoracic aortic aneurysms and aortic dissections

PURPOSE: The purpose is to report our experience and revise our previously published results in endovascular repair of short-necked thoracic aortic aneurysms or aortic type B dissections, in which the left subclavian artery (LSA) was occluded by the stent graft intentionally.METHODS: Seven patients with an aortic type B dissection and three patients who had a thoracic aortic aneurysm were treated endovascularly with stent grafts. In all patients the ostium of the LSA was occluded by the stent graft, only in two patients a primary, prophylactic revascularization of the LSA was performed by transposition to the left common carotid artery (LCA). Two types of stent grafts were used: the Talent (Medtronic) and the Excluder (Gore) stent graft. RESULTS: In all patients the sealing of the entry tear in aortic dissections and the exclusion of existing thoracic aortic aneurysms were achieved. No immediate neurological deficit or left arm ischemia occurred. Nevertheless, during a mean follow-up of 18 months (2 to 31 months) in three patients a second surgical intervention had to be performed due to subclavian steal syndrome, left arm ischemia, or continuing perfusion of the dissected false aortic channel. CONCLUSION: Intentional occlusion of the LSA in stent-graft repair of thoracic aortic diseases seems to be a safe procedure. Close follow-up is needed due to arising subclavian steal syndrome, arm ischemia, or persistent perfusion of the false channel via LSA in aortic dissections after patients' discharge, requiring surgical intervention.     

Stent grafting for aortic aneurysms

Endovascular stent grafting for aortic aneurysms/dissections using metallic stents covered with conventional vascular grafts has attracted attention as a minimally invasive alternative to open surgery. Since the first clinical experience of endovascular stent grafting for abdominal aortic aneurysm was reported in 1991, numerous clinical applications have been undertaken worldwide. Although several commercial bifurcated stent grafts for abdominal aortic aneurysm are available in various countries, including Europe, the USA, and Australia at present, none of the devices are approved for clinical use in Japan. Particularly for thoracic aortic aneurysms, hand-made devices are still used in individual institutions. Endovascular stent grafting is feasible for aneurysm repair within limited conditions. Although further investigation is necessary to clarify the indications, it is clear that aortic aneurysms could be successfully treated with precise stent-graft deployment and proper patient selection based on our 10-year follow-up results.