Usefulness of transesophageal echocardiographic monitoring to improve the outcome of stent-graft treatment of thoracic aortic aneurysms

The stent-graft procedure is becoming an alternative to surgery for treatment of many diseases of the descending thoracic aorta. This study evaluated the role of transesophageal echocardiography (TEE), used in combination with fluoroscopy and angiography, in monitoring the outcome of stent-graft placement. Twenty-two consecutive patients were submitted to stent-graft positioning in the descending aorta for various pathologies (7 patients had type B aortic dissections, 6 had thoracic aneurysms, 2 had thoraco-abdominal aneurysms, and 7 had post-traumatic aortic aneurysms). Before stent-graft deployment, TEE changed the proximal site of stent positioning initially identified by angiography in 33% of patients (5 of 15) with aortic aneurysms because of calcifications or atheromas that could interfere with stent adhesion to the aortic wall and that were not seen on angiography. In 28% of patients (2 of 7) with aortic dissection, TEE showed the guidewire in the false lumen, allowing an immediate repositioning. After stent-graft deployment, color Doppler TEE showed a perigraft leak in 7 patients, whereas angiography detected a perigraft leak in only 2 patients (p = 0.02). In 4 of these patients, further balloon expansions resulted in resolution of the leak. In the remaining 3 patients, additional stent-graft positioning was necessary. Considering the total patient cohort, TEE yielded relevant information, resulting in procedure changes in 59% (13 of 22). In conclusion, TEE provided additional information with respect to angiography in all phases of stent-graft treatment, improving immediate outcome and reducing complications.     

Endovascular stent-graft prosthesis in aortic aneurysm

Descending thoracic and abdominal aortic aneurysms represent a potential life-threatening situation. Resection and graft replacement of the pathologically altered aorta used to be the preferred method of treatment. Although progress has been achieved during the past decades in the management of patients with thoracic aortic aneurysms by new surgical techniques, intraoperative monitoring of somatosensory-evoked potentials, and spinal cord fluid drainage, postoperative morbidity and mortality rates still remain high. The afflicted population is usually of older age and present at the time of operation with various comorbidities such as hypertension, obstructive pulmonary disease, coronary heart disease, all of which with significant impact on surgical outcome. Postoperative complications, such as paraplegia, renal and pulmonary disease, contribute to prolonged hospital stay and higher medical cost. In this review we report on a promising alternative approach to the surgical treatment of thoracic and abdominal aortic aneurysms, namely the currently emerging utilization of the endovascular stent-graft prosthesis in both thoracic and abdominal aneurysm.     

Type A dissection following endovascular thoracic aortic stent-graft repair.

PURPOSE: To describe our experience with endovascular stent-graft repairs in the thoracic aorta focusing on the secondary complication of type A dissection. METHODS: Between January 1996 and April 2004, 73 patients were treated for traumatic thoracic aortic rupture (n=15), type B dissection (n=22), or atherosclerotic descending thoracic aortic aneurysms (TAA, n=36). A retrospective review of the records found 5 (6.8%) patients (3 men; median age 64 years, range 43-87) who experienced a type A dissection at a median 20 days (range 2-124) after thoracic stent-graft repair for 3 type B dissections, 1 TAA, and a late type I endoleak that appeared 28 months after initial stent-graft repair of a traumatic dissection. RESULTS: In 3 patients (2 dissections, 1 endoleak), a tear in the aortic wall at the proximal stent-graft was responsible for a retrograde type A dissection. Underlying disease was the cause of the type A dissection in the 2 other patients (1 dissection, 1 TAA) and was unrelated to the stent-grafts. Three patients underwent open surgery at 3, 26, and 124 days after stent-graft placement; 2 procedures were successful, but the third patient died 3 months later due to multiorgan failure. Two type A dissections were untreated: one patient died from cardiac tamponade 14 days after successful stent-graft exclusion of the type I endoleak; the other patient refused further treatment and survived. The procedure-related mortality following acute retrograde type A dissection was 40%. CONCLUSIONS: Endovascular stent-graft repair of the thoracic aorta is associated with lower morbidity and mortality rates than surgical repair, although potentially lethal complications, acute or delayed, may occur.     

Endovascular stent grafting of descending thoracic aortic aneurysms

The treatment of descending thoracic aortic aneurysms using endovascular stents is one of the more recent advances in treatment and is receiving increasing attention as it is a less invasive alternative to open surgical repair. Although the technology is still primitive, significant improvements have lately been made in the design and deployment of the endovascular stent-grafts. Aortic stent-grafts were used initially to exclude abdominal, and later thoracic, aortic true and false aneurysms. These prostheses have been increasingly used to treat aneurysms, dissections, and traumatic ruptures of the descending thoracic aorta with good early and mid-term outcomes. Although the long-term outcome of patients with aneurysms of the descending thoracic aorta after stent graft implantation has not been investigated, continued refinement of the endovascular approaches has decreased the need for conventional open thoracic aortic aneurysm repair, especially in patients who are at a high risk for standard surgery because of advanced age or the presence of comorbid diseases. The placement of endoluminal stent-grafts to exclude the dissected or ruptured site of thoracic aortic aneurysms is a technically feasible and relatively safe procedure. With the rapid development of endovascular approaches, the treatment of the descending thoracic aortic aneurysms might alter even more, but an extended follow-up is necessary to determine the longer term outcome. Historical perspectives, advantages, device considerations, complications, and current perspectives of the endovascular stent grafting of the descending thoracic aortic aneurysms are elaborated on.     

Endovascular stent-graft repair of acute thoracic aortic dissection--early clinical experiences

BACKGROUND: Standard treatment of acute thoracic aortic dissection type B is the medical therapy used for most patients, according to Stanford. Surgical therapy involves a high mortality rate and is reserved for patients with complicated dissections. We report from four patients with acute thoracic aortic dissection, treated endoluminally by stent-graft implantation. METHODS: Four patients with complicated acute thoracic aortic dissections type B were treated endoluminally by transfemoral stent-graft implantation. Preoperative evaluation was performed with spiral-computed tomography and calibrated aortography. The Talent stent-graft system (Metronic) was used in all patients. RESULTS: The primary entry tear could be sealed successfully and complete thrombosis of the false thoracic aortic lumen was obtained in all cases. In one patient, transposition of the left subclavian artery was performed, in two patients the stent-grafts had to be placed across the origin of the left subclavian artery. No severe intra- or postoperative complications occurred. CONCLUSION: Endoluminal treatment of acute thoracic aortic dissection seems to be a less invasive and effective therapy. Long-term results for this method are necessary.     

Elective stent-graft treatment of aortic dissections.

PURPOSE: To retrospectively review 8 years' experience with stent-graft treatment of aortic dissections at a single institution. METHODS: Forty-six patients (31 men; mean age 59 years, range 38-88) underwent stent-graft treatment for 9 Stanford type A and 37 type B aortic dissections (9 acute phase, 13 subacute, 24 chronic). Custom-designed self-expanding stainless steel Z stents covered with polytetrafluoroethylene were used (n=20) until low-profile modular stent-grafts became available for percutaneous delivery (n=26). RESULTS: Endovascular stent-graft deployment was technically successful in 44 (96%) patients; the 2 failed cases owing to intraprocedural migration and graft torsion were converted to surgery. There were 5 type I endoleaks for a clinical success (entry tear exclusion) of 85% (39/46). Complications included 3 cases of transient renal failure, 2 puncture site pseudoaneurysms, 1 guidewire-induced new intimal tear (converted), and 2 cases of stent-induced saccular aneurysms (1 converted). Follow-up at a mean 34 months (range 12-96) showed complete resolution of the thoracic false lumen in 14 (74%) of 19 acute/subacute patients treated successfully; 3 (16%) showed a reduced thoracic false lumen diameter. In the 23 chronic-phase patients treated successfully, 8 (35%) had complete resolution of the thoracic false lumen, and 11 (48%) showed size reduction. Enlargement of the abdominal aortic false lumen due to persistent flow into re-entry tear(s) occurred in 3 (13%). CONCLUSIONS: Stent-graft treatment is a feasible and effective treatment modality in aortic dissection. However, close follow-up is mandatory to monitor new intimal tear, saccular aneurysms, or enlargement of the abdominal aortic false lumen.     

带膜内支架治疗胸主动脉瘤

目的 探寻治疗胸主动脉瘤的新术式。方法 10例胸主动脉瘤病例，其中7例行单纯带膜血管内支架(stent-graft)治疗，3例夹层破裂(De Bakey I)患者行象鼻手术加带膜血管内支架置入术。结果 7例带膜血管内支架治疗组，5例成功，1例失败，1例术后死亡；3例夹层破裂手术病例均成功，恢复顺利，无并发症。结论带膜血管内支架为治疗胸降主动脉瘤的一种有效可靠方法；象鼻手术结合带膜内支架是治疗De BakeyI型的新方式，可降低手术并发症及术后病死率。     

覆膜支架腔内治疗急性胸主动脉综合征

目的 评价覆膜支架腔内治疗急性胸主动脉综合征的有效性和安全性。方法 2001年5月至2005年12月应用覆膜支架治疗57例急性胸主动脉综合征患者,其中急性主动脉B型夹层45例,穿透性粥样硬化性溃疡（PAU）或假性动脉瘤9例,创伤性胸主动脉瘤3例。建立数据库,分析其临床特点、疗效及随访结果。结果 57例患者覆膜支架置入技术成功率100％。5例有近端内漏,1例术中出现升主动脉夹层,未予特殊处理,随访结果良好;1例术后7天出现升主动脉夹层并发心包填塞死亡。5例PAU或主动脉夹层合并冠心病患者,在应用覆膜支架成功完全封闭破口后立即行冠状动脉介入治疗成功。1例出现术后一过性双下肢无力,经静脉滴注山莨菪碱和甘露醇2天后痊愈。1例支架覆盖左锁骨下动脉开口导致左椎动脉缺血,嗜睡2天后自行好转。术后重症监护病房时间1～8（平均3．5）天,术后平均住院10天。术后30天内死亡2例,1例死于升主动脉夹层破裂,1例死于急性肾衰竭。术后30天内死亡率3．5％。术后平均随访（25．3±13．1）（13—55）个月。1例于术后3个月死于大咯血,1例死因不明。1例因近端内漏行二次腔内修复术。5例患者因降主动脉覆膜支架远端再发现破口,行二次腔内修复术。术后截瘫发生率为0,无支架移位、狭窄等并发症。术后住院及随访期内总死亡率为7．0％。与传统手术相比,腔内治疗急性胸主动脉综合征具有创伤小、严重并发症少、住院时间较短的优势。结论 覆膜支架是治疗急性胸主动脉综合征优良且有效的方法,也可用于外科手术高风险患者,近中期随访结果良好,远期结果有待于进一步随访。     

Ultrafast computed tomography in the diagnosis of aortic aneurysms and dissections

UFCT, by virtue of its 50 to 400 millisecond acquisition times, 0.75 to 1.5 mm resolution, and excellent vascular opacification, provides a rapid, minimally invasive method for assessing aortic aneurysms and dissections. During a 3.5-year period, 50 patients with suspected thoracic, thoracoabdominal, and abdominal aortic aneurysms or dissections were evaluated using the Imatron C-100 UFCT scanner. Eighteen patients had thoracic or thoracoabdominal aneurysms. 17 had thoracic or thoracoabdominal dissections, 7 had abdominal aneurysms, and in 8 no aneurysms or dissections were found. In 23 of the 35 patients with thoracic or thoracoabdominal aneurysms or dissections, the UFCT findings accurately reflected the findings at aortography, surgery, or autopsy. There was one false-positive examination. The remaining 11 patients with UFCT findings of aneurysm or dissection were followed clinically. In the 7 patients with abdominal aneurysms, 4 were confirmed by angiography or surgery, and 3 were followed clinically. Of the 8 patients with negative UFCT examinations, 2 had subsequent angiography that failed to show an aneurysm, and 6 were followed from 6 to 30 months without developing findings suggestive of aneurysm. UFCT appears to be a useful, minimally invasive technique for detecting and following aortic aneurysms and dissections.     

Management of aortobronchial fistula with an aortic stent-graft.

Aortobronchial fistula presenting as massive hemoptysis is a rapidly fatal process that is extremely difficult to manage. We report a case in which endovascular occlusion of a fistula between a thoracic aortic pseudoaneurysm and lung was successfully managed by placement of an aortic endovascular stent-graft. Stent-grafting is a promising technique in managing complications of thoracic aneurysms and grafts.     

Stent-graft treatment of infected aortic and arterial aneurysms.

PURPOSE: To evaluate the feasibility and effectiveness of endovascular stent-graft repair of infected aortic and arterial aneurysms. METHODS: Eight patients (5 men; mean age 56.6 years, range 30-85) with infected saccular aneurysms in the brachiocephalic artery (n=1), proximal descending thoracic aorta (n=1), infrarenal abdominal aorta (n=3), common iliac artery (n=1), and common femoral artery (n=2) were treated with stent-graft placement and intravenous antibiotic treatment for at least 6 weeks followed by case-specific administration of oral suppressive antibiotics. All patients were considered to be in the high-surgical-risk group. RESULTS: Exclusion of the infected aneurysm was successful in all patients. However, 2 patients died within 30 days of uncontrolled sepsis, and 1 patient died at 6 months after rupture of a persistently infected aneurysm (37% mortality rate). Over a follow-up that ranged to 8 years, the 5 survivors showed complete resolution of the infected aneurysms; no stent-graft infection was observed during follow-up. CONCLUSION: The acceptable technical and clinical success of endovascular aneurysm repair makes this a promising treatment for infected aortic and arterial aneurysms. However, it is crucial that the infection is treated adequately prior to stent-graft placement.     

Nonsyndromic genetic predisposition to aortic dissection: a newly recognized, diagnosable, and preventable occurrence in families

The major diseases affecting the aorta are aortic aneurysms and dissections, with patients with acute dissections often presenting in the emergency department (ED). Recent studies demonstrate a strong genetic predisposition to thoracic aortic aneurysms and dissections, independent of syndromes traditionally considered to predispose to aortic disease (such as Marfan syndrome). Nonsyndromic familial thoracic aortic aneurysms and dissections are inherited in families as an autosomal dominant disorder and a variable age of onset of the aortic disease. The case reported here illustrates the critical importance of obtaining a family history of thoracic aortic aneurysms and dissections, along with unexplained sudden death, when assessing an individual with chest pain in the ED, regardless of age and in the absence of a known genetic syndrome.     

Genetic basis of thoracic aortic aneurysms and dissections

The major diseases affecting the aorta are aortic aneurysms and dissections, which are classified based on anatomic location. Diseases affecting the ascending aorta, such as thoracic aortic aneurysms and type I and II dissections, are primarily associated with medial necrosis on pathologic examination. Medial necrosis is characterized by fragmentation and loss of elastic fibers, loss of smooth muscle cells, and interstitial collections of collagenous tissue and basophilic ground substance. Medial necrosis occurs as part of the normal aging of the aorta but is accelerated by other conditions, including hypertension and genetic alterations that predispose persons to these aortic diseases. The etiologies of many of the genetic syndromes, such as Marfan syndrome, that predispose persons to thoracic aortic aneurysms and dissections are understood. Studies are just beginning to elucidate the genes that predispose persons without known syndromes to these aortic diseases, and a major locus for this condition, termed the TAAD1 locus, has been mapped to 5q13-14. Future characterization of this gene and others will enhance the ability to determine persons at risk for aortic aneurysms and dissections and will define molecular mechanisms involved in the pathogenesis of this disorder.     

Transluminal endovascular stent grafting of aortic dissections and aneurysms: a concise review of the major trials

Transluminal endovascular repair of the vascular system is rapidly emerging as a leading therapeutic modality for aortic dissections and aneurysms. The use of transluminal endovascular stent grafting has been used to intervene successfully on the aorta and its major branch vessels. There have been several studies examining transluminal endovascular stent grafting of thoracic aortic aneurysms, dissections, and abdominal aortic aneurysms. This paper reviews some of the major trials of transluminal endovascular stent grafting as well as its major limitation, endoleak.     

The chimney graft: a technique for preserving or rescuing aortic branch vessels in stent-graft sealing zones

PURPOSE: To report an alternative to the fenestrated stent-graft for preserving blood flow to side branches in the sealing zones of aortic stent-grafts. TECHNIQUE: A covered stent is deployed parallel to the main aortic stent-graft, protruding somewhat proximally, like a chimney, to preserve flow to a vital side branch covered by the aortic stent-graft. Use of a chimney graft makes it possible to use standard off-the-shelf stent-grafts to instantly treat lesions with inadequate fixation zones, providing an alternative to fenestrated stent-grafts in urgent cases, in aneurysms with challenging neck morphology, and for reconstituting an aortic side branch unintentionally compromised during endovascular repair. This technique has been used successfully in 10 patients, combining chimney grafts in the renal, superior mesenteric, left subclavian, left common carotid, and innominate arteries with stent-grafts in the abdominal (n=6) or thoracic (n=4) aorta. There has been no late chimney graft-related endoleak on imaging studies up to 8 months. CONCLUSION: The use of chimney grafts is feasible in the renal and superior mesenteric arteries, as well as in the supra-aortic branches, to facilitate stent-graft repair of thoracic or abdominal aortic lesions with inadequate fixation zones.     

Thoracic aorta endografts: variations in practice among medical specialists.

BACKGROUND: Endovascular stent-graft placement is emerging as a novel treatment option for patients with diseases of the descending thoracic aorta. However, currently no consensus guidelines exist to direct uniformity in stent-graft procedures as well as for pre- and postprocedural patient management, unlike that for the management of other cardiovascular disorder. Accordingly, the aim of the present survey was to assess variations in thoracic aortic stent-graft practice among different subspecialties in Germany. METHODS: An interdisciplinary questionnaire survey was conducted among 206 departments of vascular surgery, radiology, cardiology, and cardiothoracic surgery in Germany that actively performed aortic stent-graft placement. Data on preoperative procedure planning, logistics, practical/technical issues of stent-graft placement, and postoperative patient management were evaluated using a standardized, self-administered questionnaire comprising 29 items. Responses were tabulated for analysis. RESULTS: Of a total of 206 questionnaires, 184 (89.3%) were returned with 71 (38.5%) centers reporting to have performed thoracic aortic stent-graft placement (total number of procedures 2,267) through 1997 and 2003. The average number of stent-graft procedures per year was 7.4 (25-75% percentile, 2.05-10.75) at participating sites, with 49% of the respondents reporting <5 procedures per year. Treatment of thoracic aortic aneurysms was the predominant indication for stent-graft placement, followed by type B-dissection. As anticipated, marked variability existed among the different medical specialties performing stent-graft procedures with respect to all aspects of the procedures including indication for treatment, choice of preoperative and intraoperative imaging modalities, technical equipment and perioperative management. The only consistent agreement was on the need for lifelong follow-up after stent-graft placement, with CT being the preferred imaging technique (90% of centers). CONCLUSION: The present survey documents an increasing adoption of endovascular stent-graft placement for patients with diseases of the descending thoracic aorta in Germany. Despite this, there is a lack of consensus among the different medical specialties performing stent-graft placement with respect to indications and technical execution of stent-grafting. Our data supports the need for consensus practice guidelines endorsed by medical professional societies for stent-graft procedure to standardize the growing number of thoracic stent graft procedures.     

Self-Expanding Endovascular Stent-Graft Implant for Treatment of Descending Aortic Diseases

Abstract Background: Aneurysms and dissections involving the descending thoracic aorta and the distal portion of the aortic arch are difficult to resolve surgically. The introduction of endovascular self-expanding stent-grafts has simplified the operation. Given the complications associated with their peripheral placement, we explored the feasibility of surgical insertion. Methods: Thirteen patients underwent surgical insertion of a stent-graft into the aortic arch via longitudinal aortotomy. Six patients had aneurysms (ruptured in two, and seven dissections (acute in two, ruptured in one). Five patients also underwent associated procedures including aortic valve replacement (one), ascending aorta replacement (two), arch replacement (one), and coronary artery bypass (one). Results: There was one intraoperative death due to ascending aortic dissection, and two hospital deaths due to multiple complications. Of ten patients discharged, one died 3 months postoperatively. The remaining survivors are well, and imaging studies confirmed adequate correction of the aortic disease. Conclusions: The use of this technique simplifies the operation and treatment of particular cases of aortic disease. The observed morbidity and mortality are due to factors independent of the technique.     

Ascending aortic arch aneurysms and dissections: discussion and nursing management

Ascending aortic arch aneurysms and aortic dissections are serious conditions with high mortality and morbidity. Aneurysms can be defined according to morphology or location and are usually precipitated by atherosclerosis or cystic medial necrosis. Intact aortic aneurysms are often asymptomatic, while chest pain is frequently the predominant symptom associated with aortic dissections. The diverse clinical presentation of aneurysms and dissections makes diagnosis difficult. When the aneurysm is large or the patient is symptomatic, surgical intervention is the preferred treatment and consists of replacing a segment of the aorta with a synthetic graft. Postoperative nursing care focuses on altered tissue perfusion, fluid volume deficit, potential respiratory insufficiency and patient teaching.     

Multiple HIV-related aneurysms: open and endovascular treatment.

PURPOSE: To report successful endovascular repair of thoracic aortic aneurysms in 2 patients with human immunodeficiency virus (HIV). CASE REPORTS: Thoracic and abdominal aortic aneurysms (AAA) were found in a 60-year-old woman 1 year after she was diagnosed with HIV. Because of pain and risk of rupture, the AAA was repaired with conventional open techniques in February 1997, while the thoracic aneurysm was excluded in a staged procedure using a homemade endograft delivered through a 10-mm conduit sewn to the aortic tube graft. Two months later, new aneurysms were found in the superficial femoral arteries bilaterally; both were excised and replaced with vein grafts. After 7 years, the patient is well and no longer takes antiretroviral medication. Surveillance imaging shows continued patency of the stent-graft without evidence of leak or migration. In a more contemporary case, a 46-year-old man was found to have 5 focal aneurysms in the aorta; the most proximal descending thoracic aneurysm increased 2 cm in 2 weeks. The two thoracic aneurysms were successfully excluded using 2 Excluder stent-grafts. At 7 months, he was doing well, and the aneurysm had shrunk 11 mm. CONCLUSIONS: Endovascular and open treatment of HIV-related aneurysms is possible, with excellent long-term results. Patients with long-life expectancy should be treated according to the same guidelines as patients without HIV.     

Combined staged procedures for the treatment of thoracoabdominal aneurysms.

PURPOSE: To examine the efficacy of a staged approach for the treatment of thoracoabdominal aneurysms, with open visceral revascularization followed by aortic endografting, in selected patients not considered candidates for conventional surgical repair. METHODS: A retrospective review was conducted of 13 consecutive patients (8 women; mean age 64 years, range 33-77) who underwent visceral bypass followed by endovascular thoracoabdominal stent-graft implantation since 1999. Three patients presented with symptomatic aneurysms and 2 with rupture. Two patients had connective tissue disorders. All patients were deemed unfit for conventional thoracoabdominal repair due to comorbid conditions. The procedures were tailored to the pathology and specific patient anatomical situation: 5 aortic dissections with aneurysmal degeneration and 8 aneurysms (5 Crawford type II, 2 type III, and 1 type IV). RESULTS: The patients underwent retrograde visceral bypass (11 iliovisceral and 2 infrarenal aortic to visceral artery) followed by endovascular aortic relining with Zenith TX2 devices (n=7), homemade endografts (n=5), or a Talent thoracic endograft (n=1). Six patients required either a proximal or distal direct aortic repair (2 infrarenal reconstructions, 3 arch elephant trunk grafts, and 1 ascending aortic repair), while 3 patients also underwent left carotid-subclavian bypass grafting. Two patients developed paraplegia (1 following a ruptured aneurysm), and 2 patients had transient paraparetic events. Two patients had acute renal failure requiring short-term dialysis. Three patients died within 30 days; 2 late aneurysm-related deaths were noted. Three patients developed endoleaks during follow-up. Mean lengths of stay were 13 days (7-30) for the visceral bypass and 12 (3-25) for the endovascular stent-graft. In addition, remaining procedures in 8 patients required a mean of 7 days (0-14) in hospital. CONCLUSION: Staged endovascular and open procedures are feasible for thoracoabdominal aneurysms in patients at prohibitive risk for open thoracoabdominal reconstruction. However, this approach still carries a significant risk of perioperative mortality and morbidity. The potential for less invasive alternatives should be investigated.