Usefulness of transesophageal echocardiographic monitoring in transluminal endovascular stent-graft repair for thoracic aortic aneurysm

The endovascular stent-graft has been devised for the treatment of thoracic aortic aneurysm (TAA) to reduce complications associated with conventional surgical repair. The present study assessed the usefulness of transesophageal echocardiography (TEE) for intra- and post-operative examinations in patients treated with transluminal endovascular stent-graft repair for TAA. Nine patients with TAA and 2 with chronic type B aortic dissection were studied. Immediately after stent-graft deployment, perigraft leakage was evaluated with both intraoperative TEE and aortography. In 9 of 11 patients, TEE and aortography immediately after stent-graft deployment revealed the same perigraft leakage results. TEE might therefore be useful for evaluating perigraft leakage and thrombus formation after stent-graft repair for TAA and could be an alternative to aortography, especially for patients with renal dysfunction who have the possibility of contrast agent-induced complications.     

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 treatment of thoracic aortic disease: mid-term follow-up.

OBJECTIVE: The aim of this study was to evaluate the mid-term follow-up in a cohort of patients with acute or chronic descending aortic disease treated by stent-graft repair. BACKGROUND: Since 1999, endovascular stent-graft placement has been reported as an alternative treatment to surgical approach for a variety of thoracic aortic diseases; however, results beyond initial short-term follow-up are not widely available for the broad range of applications. METHODS: From March 2001, 43 consecutive patients with traumatic aortic transection (group A = 16) and complicated type B aortic dissection or aneurysm (group B = 27) underwent stent-graft implantation. All patients underwent computed tomography (CT) scan as preoperative assessment and in 26 a transesophageal echo (TEE) exam was performed. RESULTS: Technically successful stent-graft deployment was achieved in all patients. No patient required surgical conversion and no cases of paraplegia occurred. The overall in-hospital mortality was 9.3%. A residual endoleak (type II) was detected in one group B patient who was managed conservatively. The mean follow-up was 29 +/- 8 months (range 10-48 months). No patient died during late follow-up after hospital discharge. At 12 months, one patient (2.5%) who had stent graft repair of an aortic dissection developed an asymptomatic type I endoleak. Three asymptomatic patients with chronic dissection had a persistent retrograde perfusion of the thoracic false lumen via a distal tear(s) in the dissection septum. CONCLUSION: Our results of stent-graft treatment of complicated and uncomplicated diseases of the descending aorta confirms that this alternative to open repair is a safe, less invasive, and relatively low risk approach. Medium-term follow-up results suggest that it is effective and durable therapy with low associated mortality and morbidity rates.     

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.     

Clinical usefulness of transesophageal Doppler echocardiography

The usefulness of transesophageal Doppler echocardiography (TEE) was assessed in patients with various cardiovascular diseases including 15 patients with dissecting aortic aneurysm (DAA), two with thoracic aneurysm, 16 with ischemic heart disease and 14 with acquired valvular diseases. In dissecting aortic aneurysms, TEE provided clear images of the intimal flaps even in the aortic arch and descending aorta in which clear images could not be obtained by conventional external Doppler echocardiography. The entry site was detected in 11 of the 15 (73%) cases using TEE, but in only three of the 15 cases using conventional Doppler technique. In two cases of true aortic aneurysms, TEE provided clear images of the aneurysm in the descending thoracic aorta, which was discriminated precisely from DAA. In valvular disease, all four valves (aortic, pulmonary and atrio-ventricular valves) were easily observed without disturbance by any other tissues using a transesophageal approach. In addition, valve aneurysms in the posterior mitral leaflets were detected using TEE in two cases. In two cases of mitral stenosis, a thrombus was observed in the left atrial appendage. These findings were confirmed during surgery, but could not be obtained by the conventional external studies. In 16 cases, TEE was performed during aorto-coronary bypass surgery under general anesthesia. In two of these cases, left ventricular assist devices were applied after surgery. In these cases, where conventional Doppler echocardiography was not applicable, cardiac function could be monitored by TEE. Thus, TEE is useful not only in evaluating morphological function in the cardiovascular system but also in monitoring cardiac hemodynamics during and after heart surgery.     

Endovascular repair of a ruptured descending thoracic aortic aneurysm

Endovascular aneurysm repair has considerable potential advantages over the surgical approach as a treatment for thoracic aortic rupture, in part because open surgical repair of ruptured thoracic aortic aneurysms is associated with high mortality and morbidity rates. We describe the successful endovascular deployment of stent-grafts to repair a contained rupture of a descending thoracic aortic aneurysm in an 86-year-old man whose comorbidities prohibited surgery. Two months after the procedure, magnetic resonance angiography showed a patent stent-graft, a patent left subclavian artery, and complete exclusion of the aneurysm.     

Angioskopie

In complex thoracic aortic disease endovascular techniques and the use of hybrid stent grafts enables a combination therapy of the aortic arch and the descending aorta through a median sternotomy. This emphasizes the importance of intraoperative visualization of the descending aorta and its pathologies. Intraoperative angioscopy is a new diagnostic method for the assessment of distal aortic disease and assists in therapeutic decision-making and navigation of endovascular techniques in the descending aorta. This study presents the angioscopic results of 62?patients (mean age 60±12?years, 73% male, 54?aortic dissections, eight aortic aneurysms) during surgery of the thoracic aorta. Visualization of the extent of pathology along the downstream aorta was feasible in all patients. The implantation of a hybrid stent graft prosthesis was assisted by angioscopy in 34?patients and endovascular balloon dilatation of the stent graft was navigated by angioscopy in 11?patients. Angioscopy has become an indispensable tool in the intraoperative treatment of complex thoracic aortic disease in our clinic, particularly in the navigation of endovascular interventions in the distal thoracic aorta through the aortic arch.     

Stent-graft deployment to treat a perigraft seroma formed after descending thoracic aortic surgery.

PURPOSE: To report a case of stent-graft implantation for a perigraft seroma that formed after descending thoracic aortic surgery. CASE REPORT: A 70-year-old woman presented with a perigraft seroma after a descending thoracic aortic surgery 10 years ago in which a polytetrafluoroethylene graft was used. Chest radiography and computed tomography confirmed the presence of a large perigraft seroma. The previous graft was covered with a stent-graft to decrease graft porosity. At 1 year, postoperative examinations revealed a decrease in the size of the perigraft seroma. CONCLUSION: Stent-graft implantation could prove useful in cases of perigraft seromas where additional conventional surgery may pose difficulties.     

Distal Aortic Malperfusion Exacerbated by Antegrade Stent-Graft Placement During Hybrid Repair of Acute DeBakey Type I Aortic Dissection

We present the case of an acute DeBakey type I aortic dissection with malperfusion. The patient underwent valve resuspension, ascending aortic and partial arch replacement, debranching of the innominate artery, and placement of a small-diameter stent within the left common carotid artery, after which antegrade deployment of a stent-graft into the proximal descending thoracic aorta was performed to expand the true lumen. Distal malperfusion was exacerbated by the stent-graft''s traversal into the false lumen, necessitating further endovascular repair to reestablish flow to the distal aorta. Mitigation before stent-graft placement (for example, inserting a wire within the true lumen under fluoroscopic guidance to ensure stent-graft placement in the true lumen) and prompt corrective procedures are paramount, given the grim consequences of prolonged distal ischemia.     

Rapid progression of discrete type A intramural hematoma: prevention of a "procedure-related" complication by intraoperative transesophageal echocardiography.

PURPOSE: To report a case illustrating the utility of transesophageal echocardiography (TEE) before planned stent-graft placement for chronic type B aortic dissection. CASE REPORT: A 64-year-old man with acute aortic syndrome and an 8-year-old interposition graft in the distal aortic arch for acute type B dissection was referred for dissection of the descending thoracic aorta down to the aortic bifurcation; the false lumen was dilated to 65 mm and was partially thrombosed. The ascending aorta showed discrete, eccentric, 4-mm wall thickening that was not considered clinically significant. Stent-graft closure of the entry tear in the proximal descending thoracic aorta was elected. However, as the endovascular procedure was about to commence, TEE showed striking eccentric thickening of the aortic wall of up to 18 mm. The endovascular procedure was stopped, as it was decided to urgently replace the ascending aorta. The next day, the patient underwent successful ascending aortic replacement and simultaneous antegrade stent-graft implantation over the descending thoracic aortic entry tear via the open aortic arch. The postoperative course was uncomplicated, and the patient was discharged 19 days after surgery. He remains well at 6 months after the procedure. CONCLUSIONS: Our case demonstrates that dissection of the ascending aorta may occur not only due to endograft-induced intimal injury, but may also occur due to underlying but undiagnosed or underestimated disease of the ascending aorta or arch. Besides procedural guidance, intraoperative TEE is a useful tool to detect such disease to avoid subsequent "procedure-related" complications.     

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.     

Penetrating atherosclerotic aortic ulcer: documentation by transesophageal echocardiography

Objectives. This study sought to describe the ability of transesophageal echocardiography (TEE) to document the presence of penetrating atherosclerotic aortic ulcers and their complications.Background. TEE has greatly enhanced our ability to assess patients with suspected aortic disease. However, the utility of this technique in the diagnosis of penetrating atherosclerotic aortic ulcers is still undefined.Methods. TEE was performed prospectively in 194 patients to evaluate aortic disease. Twelve patients with the diagnosis of aortic ulcers or their complications were specifically studied. The diagnosis was confirmed by pathologic studies in six patients and by an additional diagnostic technique (angiography, computed tomography or magnetic resonance imaging) in the other six. All 12 patients were hypertensive and presented with chest or back pain; the mean age was 65 years (range 56 to 79). The initial working diagnosis was acute aortic dissection in nine patients. Aortic ulcers were located in the descending thoracic aorta in eight patients, the aortic arch in two and the ascending aorta in two.Results. TEE could detect aortic ulcers or their complications in 10 patients but failed to detect these lesions in the remaining 2 (1 with aortic ulcers in the distal ascending aorta and 1 with aortic ulcers in the aortic arch). In four patients, aortic ulcers were detected as a calcified focal outpouching of the aortic wall and were associated with concomitant aneurysmal dilation of the aorta in two patients and with a small localized intramural hematoma in one. TEE visualized a partially thrombosed pseudoaneurysm complicating an aortic ulcer in the descending thoracic aorta of two patients. Four patients had an aortic ulcer complicated by a “limited aortic dissection” in the descending aorta that could be detected by TEE. Five patients underwent operation, two because of aneurysmal dilation of the aorta and three because of aortic dissection; two patients died of aortic rupture; the remaining five did well (11-month follow-up) without operation.Conclusions. Aortic ulcers should be included in the differential diagnosis of chest or back pain, especially in elderly hypertensive patients. These ulcers and their complications may be recognized by TEE.     

Treatment of Type I Endoleak in an Iliac Aneurysm with Balloon Expandable Palmaz Stent

Endovascular exclusion of the peripheral arterial aneurysms with covered stent grafts have been used to decrease the operative morbidity and mortality in comorbid old patients. However, endoleaks remain a problem. The authors present a case of left common iliac artery aneurysm, which was treated by endovascular therapy. Initially, internal iliac artery was occluded with coil embolization to prevent type II endoleak. A covered self-expandable stent was used for exclusion of the aneurysm. A proximal perigraft leak was detected in control contrast injection. Palmaz balloon expandable stent was used for treatment of proximal perigraft leak. The control angiography showed complete exclusion of the aneurysm and no perigraft leak was detected in the aneurysm sac. Proximal balloon expandable stent implantation as an addition to covered stent in short and angulated necked aneurysms is technically feasible, and this technique provide a good treatment method for proximal perigraft leak.     

Feasibility of real-time magnetic resonance-guided stent-graft placement in a swine model of descending aortic dissection.

AIMS: To evaluate the pre-clinical feasibility of real-time magnetic resonance imaging (rtMRI) to guide stent-graft placement for experimental aortic dissection (AD) and to alleviate disadvantages of ionising radiation and nephrotoxic contrast media. Endovascular stent-graft placement for thoracic aortic disease is usually performed under X-ray guidance. The feasibility of rtMRI-guided stent-graft placement is currently not known. METHODS AND RESULTS: By using a catheter-based technique, dissections of the descending thoracic aorta were successfully created in eight domestic pigs. Subsequent implantation of commercially available, nitinol-based stent-grafts was performed entirely under rtMRI guidance. By pre-interventional MRI, the mean minimal true-lumen diameter was 0.9 (0.825-0.975) cm. rtMRI permitted not only the successful and safe device navigation within the true lumen from the iliac arteries to the thoracic aorta, but also the precise positioning and deployment of the stent-graft and safe withdrawal of the delivery catheter in seven of eight pigs. This was achieved without any other complications. After the stent-graft placement, MRI demonstrated complete obliteration of the false lumen, which was confirmed at autopsy. All stent-grafts were well expanded resulting in an increase in the size of the true-lumen diameter to 2.05 (1.925-2.1) cm (P=0.066 vs. baseline). CONCLUSION: In experimental AD, rtMRI-guided endovascular stent-graft placement is feasible and safe and has the potential for mitigating radiation and contrast-related side effects. Additionally, it allows not only pre-interventional diagnosis and detailed anatomic diagnosis, but also permits immediate post-interventional, anatomical, and functional delineation of procedure success that may serve as a baseline for future comparison during follow-up.     

Comparison of a percutaneous separate stent endograft and a conventional thoracic stent-graft for endovascular repair of type B aortic dissection.

PURPOSE: To compare the immediate and midterm outcomes of aortic dissection repair with a separate stent endograft (SSE) versus a conventionally constructed thoracic stent-graft. METHODS: The records of 35 patients treated for type B aortic dissection from September 1997 to April 2003 were reviewed. Seventeen patients (12 men; mean age 58.8+/-11.6 years) underwent endovascular repair with a separate stent endograft (SSE), a custom-made device with a reduced profile suitable for percutaneous introduction through a 12-F sheath. Eighteen patients (10 men; mean age 56.1+/-12.8 years) underwent treatment with a conventional custom-made stent-graft. RESULTS: Angiographic success was achieved in 13/17 (76.5%) of the SSE-treated patients and 12/18 (66.7%) for the conventional device group (p=0.521). Clinical success (complete obliteration/thrombosis of the false lumen) was achieved in 12/17 (70.6%) and 11/18 (61.1%), respectively (p=0.555). There were 2 cases of stent-graft movement during deployment and 2 access site complications in the conventional stent-graft group, whereas the SSE patients had no complications. Except for 2 conventional stent-graft patients who were lost to follow-up, all patients are alive at a mean 19.5+/-11.6 months for the SSE group and 34.2+/-21.5 months for the conventional stent-graft patients. CONCLUSIONS: The separate stent endograft can be deployed percutaneously without the need for blood pressure reduction, achieving accurate deployment without migration. In this small clinical experience, patients treated with the SSE had no access site complications and demonstrated midterm results comparable to the conventional stent-graft cohort, suggesting the possible usefulness of this device for the treatment of thoracic aortic dissection.     

Restoration of the thoracic aorta in Type A dissection with hybrid prosthesis

Following successful repair of Type A dissection, late morbidity and mortality depend on the progression of residual chronic Type B dissection. To avoid the development of late aneurysms of the descending thoracic aorta, a persistent aortic false lumen around the stent-graft can be prevented by remodeling the thoracic aorta. Ten consecutive patients (mean age: 56 years) with acute Type A dissection underwent a "frozen elephant trunk operation" with the E-vita hybrid prosthesis, under deep hypothermic circulatory arrest, between October 2009 and April 2010. The thoracic aorta was restored to its original size. Computed tomography was used to size the aortic diameter. All patients survived and were routinely discharged. Postoperative computed tomography showed no remaining false lumen and no distal organ ischemia in any patient. No new neurological complication was recorded. Two patients suffered postoperative pulmonary arterial embolism; one underwent embolectomy. Restoration of the thoracic aorta is a safe procedure to close the false lumen during the primary operation for acute Type A dissection. However, the diameter of the stent should reflect the overall aortic size, independent of the diameter of the true lumen.     

Expanding false lumen in the abdominal aorta 5 years after endovascular repair of a type B aortic dissection: successful exclusion of 3 distal re-entry sites.

PURPOSE: To report endovascular treatment of an expanding aneurysmal false lumen several years after successful stent-graft deployment in the descending thoracic aorta for type B aortic dissection. CASE REPORT: A 54-year-old woman who had a stent-graft placed at the entry site of a type B aortic dissection 5 years prior presented with abdominal discomfort and palpable abdominal mass. Successful remodeling of the thoracic aorta was demonstrated by computed tomography; however, a false lumen aneurysm in the abdominal aorta had expanded from 4.8 to 6.5 cm and caused symptoms. She was successfully treated with 3 additional stent-grafts at 3 re-entry sites. Six months after the procedure, the false lumen aneurysm was completely excluded. CONCLUSIONS: Endovascular repair of the re-entry sites can prevent further expansion of false lumen aneurysm, which occurs in some patients with type B dissection treated with stent-grafts.     

胸主动脉病变术中应用经食管超声心动图的初步探讨

目的：探讨胸主动脉疾病的术中应用经食管超声心动图（ＴＥＥ）的价值及适应证。方法：本文报道８例（１５～６３岁，平均年龄４４．５岁）不同类型胸主动脉疾病术中ＴＥＥ监测结果。病例包括先天性主动脉瓣上狭窄、升主动脉瘤、主动脉夹层及主动脉夹层伴假性动脉瘤、胸降主动脉假性动脉瘤、主动脉瓣脱垂等。结果：８例患者的术中检查与术前诊断全部吻合。术中ＴＥＥ发现１例主动脉夹层累及左锁骨下动脉，而术前磁共振成像未能提示。此外，术中ＴＥＥ还显示２例胸降主动脉内的粥样硬化斑块。结论：初步显示术中ＴＥＥ可即刻评价手术效果，对拟行主动脉瓣成形术的患者最有价值；为避免升主动脉粥样斑块的脱落导致术后体循环尤其是脑栓塞，对于高龄患者也积极提倡术中ＴＥＥ监测。     

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。     

Stent graft treatment for transverse arch and descending thoracic aorta aneurysms

PURPOSE OF REVIEW: The aim of this article is to review the recent relevant literature on endovascular repair of thoracic aortic aneurismal disease. RECENT FINDINGS: The introduction of endovascular stent graft technology has ushered in a new era in therapy for diseases of the aortic arch and descending thoracic aorta. The technical challenges of stent graft deployment in the descending thoracic aorta, such as proximity to the great vessels and arch tortuosity, have been and remain a device engineering focus. More recently, repair of aortic arch aneurysms has been accomplished using both 'hybrid' (open and endovascular) and totally endovascular techniques. SUMMARY: Endovascular stent grafting of aneurismal disease processes of the thoracic aorta is feasible and relatively safe. Exquisite judgment is essential for good results. These results generally rest on a broad knowledge base of thoracic aortic disease processes and experience in both open and endovascular surgery. Careful attention to patient anatomy and device specifications must be maintained. The key to the successful implementation of this technology lies in careful preoperative planning, intraoperative execution with safe device delivery, and prevention of central nervous system injury. Routine follow-up imaging is imperative to better understand the long-term results and indications for these new procedures.