Thoracic aortic stent grafting: Improving results with newer generation investigational devices

Outcomes and survival following thoracic endovascular repair in patients with aortic aneurysms limited to the descending thoracic aorta

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) is a well-established therapy for descending aortic aneurysms (DTA). There is a paucity of large series reporting the mid- and long-term outcomes from this era. The main aim of this study was to evaluate the outcomes of TEVAR with regards to the effect of aortic morphology and procedure-related variables on survival, reintervention and freedom from endoleaks.

METHODS

In this retrospective single center study, we evaluated the clinical outcomes among 158 consecutive patients with DTA than underwent TEVAR between 2006 and 2019 at our center. The cohort included 51% patients with device landing zones proximal to the subclavian artery and 25.9% patients undergoing an emergent or urgent TEVAR. The primary outcome was survival, and secondary outcomes were reintervention and occurrence of endoleaks.

RESULTS

Median follow-up was 33 months [IQR 12 to 70] while 50 patients (30.6%) had longer than 5-year follow-up. With a median patient age of 74 years, post-operative Kaplan Meyer survival estimates were 94.3% (95%CI 90.8-98.0, SE 0.018%) at 30 days, 76.4% (95%CI 70.0-83.3, SE 0.034%) at one year and, 52.9% (95%CI 45.0-62.2, SE 0.043%) at five years. Freedom from reintervention at 30 days, one year, and five years was 92.9% (95%CI 89.0-97.1, SE 0.021%), 80.0% (95%CI 72.6-88.1, SE 0.039%), and 52.8% (95%CI 41.4-67.4, SE 0.065%), respectively. On cox regression analysis greater aneurysm diameter, and the use of device landing zones in aortic regions 0-1 were associated with an increased probability of all-cause mortality, and with reintervention during follow-up. Independent of aneurysm size undergoing urgent or emergent TEVAR was associated with higher mortality risk for the first three years post-operative but not on long-term follow-up.

CONCLUSIONS

Larger aneurysms and those requiring stent-graft landing in aortic zones 0 or 1, are associated with higher risk for mortality and reintervention. There remains a need to optimize clinical management and device design for larger proximal aneurysms.

Three-year follow-up of aortic arch endovascular stent grafting with the Nexus device: results from a prospective multicentre study

OBJECTIVES

Endovascular aortic arch stent grafting with branched devices has shown initial promising results. The aim of this prospective, multicentre study was to evaluate 3-year outcomes of aortic arch stent grafting with NEXUS® Aortic Arch Stent Graft System (Nexus), a single-branch, bi-modular, off-the-shelf aortic arch stent graft system in high-risk patients.

METHODS

Patients treated with Nexus, either under the feasibility clinical study or as compassionate use procedures in 5 centres, were included in this study. The primary end point was overall survival. The secondary end points included the incidence of procedure-related unplanned intervention, stroke, paraplegia and endoleak. Clinical and radiologic follow-up was performed at each study site at 30 days, 6 months and on a yearly basis thereafter up to 3 years postoperatively.

RESULTS

We analysed data from a total of 28 patients. The overall median follow-up was 1132 (interquartile range: 809-1537). There were no device or procedure-related deaths between 1 and 3 years. Overall survival at 1 and 3 years was 89% and 71%, respectively. The cumulative incidence of unplanned reintervention at 1 and 3 years was 11% and 29%, respectively. There were no reports of stroke, paraplegia, aneurysm rupture, myocardial infarction or new aortic valve insufficiency. In this study's 1-3 year follow-up period, 1 type Ib (4%), 1 type II (4%) and 2 type III (8%; between Nexus' distal end and Thoracic endovascular aortic repair (TEVAR) extensions) endoleak were detected.

CONCLUSIONS

Endovascular aortic arch exclusion with the single-branch, off-the-shelf Nexus system provides promising clinical and radiologic results at 3-year follow-up in a high-risk patient cohort.

Research and clinical translation of trilayer stent-graft of expanded polytetrafluoroethylene for interventional treatment of aortic dissection

The aortic dissection (AD) is a life-threatening disease. The transcatheter endovascular aortic repair (EVAR) affords a minimally invasive technique to save lives of these critical patients, and an appropriate stent-graft gets to be the key medical device during an EVAR procedure. Herein, we report a trilayer stent-graft and corresponding delivery system used for the treatment of the AD disease. The stent-graft is made of nitinol stents with an asymmetric Z-wave design and two expanded polytetrafluoroethylene (ePTFE) membranes. Each of inner and outer surfaces of the stent-graft was covered by an ePTFE membrane, and the two membranes were then sintered together. The biological studies of the sintered ePTFE membranes indicated that the stent-graft had excellent cytocompatibility and hemocompatibility in vitro. Both the stent-graft and the delivery system exhibited satisfactory mechanical properties and operability. The safety and efficacy of this stent-graft and the corresponding delivery system were demonstrated in vivo. In 9 canine experiments, the blood vessels of the animals implanted with the stent-grafts were of good patency, and there were no thrombus and obvious stenosis by angiography after implantation for 6 months. Furthermore, all of the 9 clinical cases experienced successful implantation using the stent-graft and its post-release delivery system, and the one-year follow-ups indicated the preliminary safety and efficacy of the trilayer stent-graft with an asymmetric Z-wave design for interventional treatment.

Review of Type III Endoleaks

Endoleak remains a significant challenge to endovascular aneurysm repair, particularly as evolving techniques and devices have allowed treatment of increasingly complex aneurysm anatomy with increasing number of device components. Intervention is recommended for both type I and III endoleaks due to their risk of rupture, and endovascular techniques are the favored modality with placement of a bridging endograft over the endoleak defect. Conversion to open surgical repair remains the definitive option in cases where less invasive methods have failed or are precluded. In this article, the authors review evidence on the etiology, incidence, diagnosis, and current techniques for type III endoleak management.

Outcomes of a Spinal Drain and Intraoperative Neurophysiologic Monitoring Protocol in Thoracic Endovascular Aortic Repair

BACKGROUND

Adjuncts for early detection and treatment of spinal cord ischemia (SCI) in thoracic aortic surgery are supported by robust clinical experience in open repair. The utility of cerebrospinal fluid (CSF) drainage and neurophysiologic monitoring (NPM) in thoracic endovascular aortic repair (TEVAR) is less clear. The purpose of this investigation is to determine the influence of a selective institutional spinal cord protection protocol using prophylactic NPM and CSF on outcomes for standard TEVAR.

METHODS

Patients undergoing standard TEVAR entered into a prospectively maintained database from a single institution from 2007 to 2016 were retrospectively reviewed. Preoperative characteristics, aneurysm extent, and etiology were reviewed. Utilization of CSF drains including volume of fluid removed, duration of drainage, and catheter-related complications were collected. NPM data were reviewed to determine the influence on intraoperative management. Exact logistic regression was used to identify independent predictors of SCI.

RESULTS

Of 223 patients undergoing TEVAR, 130 met inclusion criteria for the study. CSF drains were used in 71 patients (54.6%), and 56 of 130 (43%) had NPM. SCI occurred in 7 patients (5.4%), of whom 5 had partial or complete recovery. Median time to symptoms of SCI was delayed in all cases (median 52 hr, range 8-312), and none of the 4 of 7 patients with adjunct NPM demonstrated intraoperative changes. Intraoperative changes in NPM occurred in 26 (46%), and represented unilateral leg ischemia in all but 2 cases. In both patients, changes consistent with SCI were associated with intraoperative hypotension and resolved with blood pressure augmentation. Neither patient developed postoperative SCI. Median length of stay (22 vs. 9 days, P = 0.012), operative room time (262 vs. 209, P = 0.040), and perioperative mortality (28.6% vs. 4.1%, P = 0.046) were significantly higher for patients with SCI versus those without. Length of aortic coverage was found to be the sole independent predictor of SCI (odds ratio 8.2, P = 0.026). Complications related to CSF drainage occurred in 4 patients (5.6%) with major complications occurring in 2 patients (2.8%), including 1 with an intrathecal hematoma and permanent bilateral paraparesis.

CONCLUSIONS

Selective use of prophylactic CSF drainage in TEVAR was associated with moderate risk and questionable benefit. The use of neurophysiological monitoring allowed for early detection and treatment of spinal ischemia, but its utility is limited by logistical factors and to the minority of patients with intraoperative spinal ischemic events.

Late type III endoleak after thoracic endovascular aneurysm repair and previous infrarenal stent graft implantation - a case report and review of the literature

Thoracic endovascular aortic repair (TEVAR) effectively improved the results of thoracic aortic aneurysm treatment. TEVAR is a less invasive procedure that can be performed under local anesthesia with shorter hospital stay. The perioperative morbidity and mortality rates are lower for endovascular than open repair, but the rate of secondary interventions is higher for TEVAR. We report a case of an elderly man with synchronous abdominal and thoracic aortic aneurysms. A type III dangerous endoleak was recognized 3 years after TEVAR. It was successfully repaired during an endovascular procedure. There were no new endoleaks after 12 months of follow-up. TEVAR may be the only option of treatment for risky and elderly patients. However, postoperative monitoring is necessary to exclude different types of endoleaks. Most of them undergo effective endovascular repair.

A History of Thoracic Aortic Surgery

Ancient historical texts describe the presence of aortic pathology conditions, although the surgical treatment of thoracic aortic disease remained insurmountable until the 19th century. Surgical treatment of thoracic aortic disease then progressed along with advances in surgical technique, conduit production, cardiopulmonary bypass, and endovascular technology. Despite radical advances in aortic surgery, principles established by surgical pioneers of the 19th century hold firm to this day.

Management of Aortic Aneurysms and Dissections with the Zenith TX2 Stent Graft

Endovascular repair of thoracic aortic aneurysms offers a less invasive alternative to conventional surgery, similar to its counterpart in the abdominal aorta. Although its long-term durability and outcome remain relatively unknown, published midterm results from clinical trials suggest comparable rates of aneurysm-related mortality and significant reductions in early morbidity compared with open repair. The Zenith TX2 stent graft (Cook Endovascular, Bloomington, IN) is an investigational endovascular device that is designed to treat aneurysms and other degenerative pathologies of the thoracic aorta. At the time of this writing, it is nearing completion of its pivotal trial. Clinical experience with this device is limited to countries outside the United States and to sites participating in the clinical trials. The purpose of this article is to provide a description of the Zenith TX2 device and its application in the repair of thoracic aortic aneurysms and dissections.

Thoracic stent graft versus surgery for thoracic aneurysm

BACKGROUND

Thoracic aortic aneurysm (TAA) is an uncommon disease with an incidence of 10.4 per 100,000 inhabitants. It occurs mainly in older individuals and is evenly distributed among both sexes. There are no signs or symptoms indicative of the presence of the disease. Progressive but unpredictable enlargement of the dilated aorta is the natural course of the disease and can lead to rupture. Open chest surgical repair using prosthetic graft interposition has been a conventional treatment for TAAs. Despite improvements in surgical procedures perioperative complications remain significant. The alternative option of thoracic endovascular aneurysm repair (TEVAR) is considered a less invasive and potentially safer technique, with lower morbidity and mortality compared with conventional treatment. Evidence is needed to support the use of TEVAR for these patients, rather than open surgery. This is an update of the review first published in 2009.

OBJECTIVES

This review aimed to assess the efficacy of TEVAR versus conventional open surgery in patients with thoracic aortic aneurysms.

SEARCH METHODS

For this update the Cochrane Vascular Information Specialist searched the Specialised Register (last searched January 2016) and CENTRAL (2015, Issue 12).

SELECTION CRITERIA

Randomised controlled trials in which patients with TAAs were randomly assigned to TEVAR or open surgical repair.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified and evaluated potential trials for eligibility. Excluded studies were further checked by another author. We did not perform any statistical analyses as no randomised controlled trials were identified.

MAIN RESULTS

We did not find any published or unpublished randomised controlled trials comparing TEVAR with conventional open surgical repair for the treatment of thoracic aortic aneurysms.

AUTHORS' CONCLUSIONS

Stent grafting of the thoracic aorta is technically feasible and non-randomised studies suggest reduction of early outcomes such as paraplegia, mortality and hospital stay. High quality randomised controlled trials assessing all clinically relevant outcomes including open-conversion, aneurysm exclusion, endoleaks, and late mortality are needed.

Endovascular Treatment of Degenerative Aneurysms Involving Only the Descending Thoracic Aorta

Purpose: To determine the efficacy of thoracic endovascular aortic repair (TEVAR) for degenerative aneurysm involving only the descending thoracic aorta (DTAA). Methods: An English-language literature review was performed through PubMed, Scopus, and Google Scholar to identify any study evaluating the outcomes of TEVAR for DTAA. The main endpoints of this analysis were all-cause 30-day and late postoperative mortality. Secondary outcome measures were procedure success, vascular access complications, paraplegia, stroke, early endoleaks during the index hospitalization, aneurysm-related death, reinterventions, and conversion to open repair. To control for the anticipated heterogeneity among small observational studies, absolute values and means were pooled using random effects models; the results are expressed as pooled proportions, means, or risk ratio (RR) with 95% confidence intervals (CIs). Results: Eleven studies reporting on 673 patients (mean age 72.6 years, mean aneurysm diameter 62.9 cm) with DTAA were selected for the analysis. Technical success was reported in 91.0% of patients, and vascular access complications requiring repair were encountered in 9.7% of cases. Pooled overall 30-day, 1-year, 2-year, and 3-year survival rates were 96.0%, 80.3%, 77.3%, and 74.0%, respectively. Five studies compared the results of TEVAR after elective (n=151) and urgent/emergent procedure (n=77); the latter was a predictor of 30-day mortality (17.1% vs 1.8%, RR 3.83, 95% CI 1.18 to 12.40, p=0.025). Paraplegia occurred in 3.2% of patients and was permanent in 1.4% of patients. The stroke rate was 2.7%. Early type I endoleak was observed in 7.3%, type II endoleak in 2.0%, and type III in 1.2% of patients. The mean follow-up of 9 studies was 22.3 months. At 3 years, freedom from reintervention was 90.3%. Death secondary to aneurysm rupture and/or fistula was reported in 3.2% of patients. Conclusion: Current results indicate that TEVAR for DTAA can be performed with rather high technical success, low postoperative morbidity, and good 3-year survival.

Thoracic stent graft versus surgery for thoracic aneurysm

BACKGROUND

Thoracic aortic aneurysm (TAA) is an uncommon disease with an incidence of 10.4 per 100,000 inhabitants. It occurs mainly in older individuals and is evenly distributed among both sexes. There are no signs or symptoms indicative of the presence of the disease. Progressive but unpredictable enlargement of the dilated aorta is the natural course of the disease and can lead to rupture. Open chest surgical repair using prosthetic graft interposition has been a conventional treatment for TAAs. Despite improvements in surgical procedures perioperative complications remain significant. The alternative option of thoracic endovascular aneurysm repair (TEVAR) is considered a less invasive and potentially safer technique, with lower morbidity and mortality compared with conventional treatment. Evidence is needed to support the use of TEVAR for these patients, rather than open surgery.

OBJECTIVES

The aim of this review is to assess the efficacy of TEVAR versus conventional open surgery in patients with TAAs.

SEARCH METHODS

For this update the Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched March 2013) and CENTRAL (2013, Issue 2).

SELECTION CRITERIA

Randomised controlled trials in which patients with TAAs were randomly assigned to TEVAR or open surgical repair.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified and evaluated potential trials for eligibility. Excluded studies were further checked by another author. We did not perform any statistical analyses as no randomised controlled trials were identified.

MAIN RESULTS

We did not find any published or unpublished randomised controlled trials comparing TEVAR with conventional open surgical repair for the treatment of thoracic aortic aneurysms.

AUTHORS' CONCLUSIONS

Though stent grafting of the thoracic aorta is technically feasible and non-randomised studies suggest reduction of early outcomes such as paraplegia, mortality and hospital stay, high quality randomised controlled trials assessing all clinically relevant outcomes including open-conversion, aneurysm exclusion, endoleaks, and late mortality are needed.

Acute Traumatic Thoracic Aortic Injury: Considerations and Reflections on the Endovascular Aneurysm Repair

Traumatic rupture of the thoracic aorta is a life-threatening lesion and it occurs in 10 to 30% of fatalities from blunt thoracic trauma and is the second most common cause of death after head injury. Immediate surgery is often characterized by a high mortality and morbidity rate. Delayed repair of traumatic aortic injuries has significant survival benefits and a much lower mortality rate compared with early open repair. Despite developments in operative techniques, there still remains considerable operative mortality and morbidity associated with a surgical approach even if delayed. Endovascular stent grafts for the thoracic aorta represents an alternative to the conventional approach for traumatic aortic rupture. Because of the lower invasivity avoiding thoracotomy and use of heparin, endovascular repair can be applied in acute patients without the risk of destabilizing pulmonary, head or abdominal traumatic lesions. However, despite the good deal of convincing evidence for endovascular treatment for thoracic aortic diseases and for traumatic aortic injuries as a valid and efficacious alternative to surgery, several reports show a variety of late complications of thoracic endografts especially for first-generation stent-grafts. In light of this, is the endovascular treatment really safe, efficacious and free from complications in the long term? This manuscript aims to offer a moment of reflection on this important chapter of aortic pathology.

Endovascular repair of thoracic aortic aneurysms

Degenerative aneurysms of the thoracic aorta are increasing in prevalence; open repair of descending thoracic aortic aneurysms is associated with high rates of morbidity and mortality. Repair of isolated descending thoracic aortic aneurysms using stent grafts was introduced in 1995, and in an anatomically suitable subgroup of patients with thoracic aortic aneurysm, repair with endovascular stent graft provides favorable outcomes, with decreased perioperative morbidity and mortality relative to open repair. The cornerstones of successful thoracic endovascular aneurysm repair are appropriate patient selection, thorough preprocedural planning, and cautious procedural execution, the elements of which are discussed here.

Neurological complications of thoracic endovascular aortic repair

Thoracic endovascular aortic repair (TEVAR) has decreased the morbidity and mortality associated with open surgical repair of descending thoracic aortic diseases, but important complications unique to the procedure remain. Spinal cord ischemia and infarction is a recognized complication caused by endovascular coverage or injury to spinal cord collateral vessels. Stroke is a consequence of thromboembolism or coverage of aortic arch branch vessels with insufficient collateral circulation. Understanding the risk factors and the pathophysiology of neurological complications of TEVAR are important for the successful anesthetic and surgical management and treatment of patients undergoing endovascular procedures involving the thoracic aorta.

Thoracic aortic aneurysms and dissections: endovascular treatment

The treatment of thoracic aortic disease has changed radically with the advances made in endovascular therapy since the concept of thoracic endovascular aortic repair was first described 15 years ago. Currently, there is a diverse array of endografts that are commercially available to treat the thoracic aorta. Multiple studies, including industry-sponsored and single-institution reports, have demonstrated excellent outcomes of thoracic endovascular aortic repair for the treatment of thoracic aortic aneurysms, with less reported perioperative morbidity and mortality in comparison with conventional open repair. Additionally, similar outcomes have been demonstrated for the treatment of type B dissections. However, the technology remains relatively novel, and larger studies with longer term outcomes are necessary to more fully evaluate the role of endovascular therapy for the treatment of thoracic aortic disease. This review examines the currently available thoracic endografts, preoperative planning for thoracic endovascular aortic repair, and outcomes of thoracic endovascular aortic repair for the treatment of both thoracic aortic aneurysms and type B aortic dissections. Mt Sinai J Med 77:256-269, 2010. (c) 2010 Mount Sinai School of Medicine.

Endovascular repair of nonruptured thoracic aortic aneurysms: systematic review

Thoracic aortic aneurysms represent a major health problem. Untreated thoracic aortic aneurysms may rupture, which has a dismal outcome. The standard treatment for thoracic aneurysms is open surgical repair, but it is associated with high mortality and morbidity. Endovascular repair provides a less invasive and safer alternative. A systematic review was performed of all published literature on the above subject. Our primary objective was to measure 30-day mortality for nonruptured thoracic aortic aneurysms. Studies describing other pathologies, such as aortic dissection, mycotic aneurysms, penetrating ulcers, traumatic transactions, and pseudoaneurysms, and studies from which independent data for thoracic aortic aneurysm could not be separately extracted were excluded. Case series describing less than 10 patients and all case series describing ruptures or concealed ruptures were excluded as well. Twenty-six case series and one comparative study were identified. This formed a cohort of 1,038 patients. Technical success was possible in more than 97% of patients. The 30-day mortality was calculated to be 5.1% even though the group under study was mostly those who were refused surgery by a surgeon or had a higher surgical risk. The incidence of paraplegia and stroke was 3.1% and 4.7%, respectively. Early endoleak was seen in 16.7% of patients, whereas 11.7% of patients developed late endoleak, but most did not require any additional procedure. The rate of reintervention was 14.9%. The 12-month mortality rate was 14.2%. Endovascular repair shows encouraging short-term results. It is associated with significantly less mortality and morbidity, but long-term results need to be further investigated.

Endovascular approach to acute aortic trauma

Traumatic thoracic aortic injury remains a major cause of death following motor vehicle accidents. Endovascular approaches have begun to supersede open repair, offering the hope of reduced morbidity and mortality. The available endovascular technology is associated with specific anatomic considerations and complications. This paper will review the current status of endovascular management of traumatic thoracic aortic injuries.

Current management of traumatic rupture of the descending thoracic aorta

Traumatic rupture of the descending thoracic aorta remains a leading cause of death following major blunt trauma. Management has evolved from uniformly performing emergent open repair with clamp and sew technique to include open repair with mechanical circulatory support, medical management and most recently, endovascular repair. This latter approach appears, in the short term, to be associated with perhaps better outcome, but long term data is still accruing. While an attractive option, there are specific anatomic and physiologic factors to be considered in each individual case.

Thoracic stent graft versus surgery for thoracic aneurysm

BACKGROUND

Thoracic aortic aneurysm (TAA) is an uncommon disease with an incidence of 10.4 per 100,000 inhabitants. It occurs mainly in older individuals and is evenly distributed among both sexes. There are no signs or symptoms indicative of the presence of the disease. Progressive but unpredictable enlargement of the dilated aorta is the natural course of the disease and can lead to rupture. Open chest surgical repair using prosthetic graft interposition has been a conventional treatment for TAAs. Despite improvements in surgical procedures perioperative complications remain significant. The alternative option of thoracic endovascular aneurysm repair (TEVAR) is considered a less invasive and potentially safer technique, with lower morbidity and mortality compared with conventional treatment. Evidence is needed to support the use of TEVAR for these patients, rather than open surgery.

OBJECTIVES

The aim of this review is to assess the efficacy of TEVAR versus conventional open surgery in patients with TAAs.

SEARCH STRATEGY

The Cochrane Peripheral Vascular Diseases Group searched their Trials Register (last searched 10 October 2008), the Cochrane Central Register of Controlled Trials database (CENTRAL) (last searched The Cochrane Library 2008, Issue 4).

SELECTION CRITERIA

Randomised controlled trials in which patients with TAAs were randomly assigned to TEVAR or open surgical repair.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified and evaluated potential trials for eligibility. Excluded studies were further checked by another author. We did not perform any statistical analyses as no randomised controlled trials were identified.

MAIN RESULTS

We did not find any published or unpublished randomised controlled trials comparing TEVAR with conventional open surgical repair for the treatment of thoracic aortic aneurysms.

AUTHORS' CONCLUSIONS

Though stent grafting of the thoracic aorta is technically feasible and non-randomised studies suggest reduction of early outcomes such as paraplegia, mortality and hospital stay, high quality randomised controlled trials assessing all clinically relevant outcomes including open-conversion, aneurysm exclusion, endoleaks, and late mortality are needed.

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.

Degree of fusiform dilatation of the proximal descending aorta in type B acute aortic dissection can predict late aortic events

OBJECTIVE

Predicting the risk factors for late aortic events in patients with type B acute aortic dissection without complications may help to determine a therapeutic strategy for this disorder. We investigated whether late aortic events in type B acute aortic dissection can be predicted accurately by an index that expresses the degree of fusiform dilatation of the proximal descending aorta during the acute phase; this index can be calculated as follows: (maximum diameter of the proximal descending aorta)/(diameter of the distal aortic arch + diameter of the descending aorta at the pulmonary artery level).

METHODS

Patients with type B acute aortic dissection without complications (n = 141) were retrospectively analyzed to determine the predictors of late aortic events; these include aortic dilatation, rupture, refractory pain, organ ischemia, rapid aortic enlargement, and rapid enlargement of ulcer-like projections.

RESULTS

The fusiform index in patients with late aortic events (0.59) was higher than that in patients without late aortic events (0.53, P < .01). Patients with a higher fusiform index exhibited aortic dilatation earlier than those with a lower fusiform index. By multivariate analysis, we conclude that the predominant independent predictors of late aortic events were a maximum aortic diameter of 40 mm or more, a patent false lumen, and a fusiform index of 0.64 or more (hazard ratios, 3.18, 2.64, and 2.73, respectively). The values of actuarial freedom from aortic events for patients with all 3 predictors at 1, 5, and 10 years were 22%, 17%, and 8%, respectively, whereas the values in those without these predictors were 97%, 94%, and 90%, respectively.

CONCLUSIONS

The degree of fusiform dilatation of the proximal descending aorta, a patent false lumen, and a large aortic diameter can be predominant predictors of late aortic events in patients with type B acute aortic dissection. Patients with these predictors should be recommended to undergo early interventions (surgery or stent-graft implantation) or at least be closely followed up during the chronic phase before such events develop.

The Hybrid Total Arch Repair: Brachiocephalic Bypass and Concomitant Endovascular Aortic Arch Stent Graft Placement

BACKGROUND

Repair of aortic arch aneurysm is technically demanding, requiring complex circulatory management. Very large atherosclerotic saccular aneurysms of the arch are grave markers of extensive arch and brachiocephalic atheromatous disease and represent high surgical risks for perioperative neurologic complications. Operative morbidity and mortality may be prohibitive with traditional surgical intervention. We described our experience with a hybrid procedure for total arch repair with a brachiocephalic bypass with a trifurcated graft followed by concomitant placement of a stent graft in the arch.

METHODS

Since June 2005, we have performed the hybrid total arch repair in eight patients. A retrospective review was performed to evaluate the new technique.

RESULTS

The mean age of the patients was 67 years with a mean aneurysm size of 8 cm (range, 4.4 to 10 cm). Significant comorbidities included carotid stenosis, chronic renal insufficiency, peripheral vascular disease, hypertension, and coronary artery disease. Two patients had previous Abdominal aortic aneurysm (AAA) repairs. Three patients had previous sternotomy for type A dissection, ascending aortic aneurysm repair, and coronary artery bypass grafting. Transesophageal echocardiogram demonstrated grade IV or V atheromatous disease in the arch and ascending aorta. Stent grafts were deployed antegrade directly into the ascending aorta in three patients and retrograde from the femoral artery in five patients. Technical success with complete aneurysmal exclusion was achieved in all patients (100%). At a mean follow-up period of 11.7 months, there was no incidence of endoleak. There was one death resulting from a perioperative myocardial infarction (first patient). Documented perioperative neurologic events (stroke) occurred in two patients, with both patients demonstrating no residual deficit at the time of discharge.

CONCLUSIONS

Saccular arch aneurysms can be technically treated by total arch repair with brachiocephalic bypass and concomitant aortic arch stent graft placement. Hybrid arch repair provides an alternative to patients otherwise considered prohibitively high risk for traditional open arch repair.

The Endovascular Approach to Acute Aortic Trauma

Endovascular repair of the traumatically injured thoracic aorta has emerged as an exceptionally promising modality that is typically quicker than open repair, with a reduced risk of paralysis. There are a specific set of anatomic criteria that need to be applied, which can be rapidly assessed by the CT angiogram. The enthusiasm for endovascular repair must be tempered by recognition of the complications and lack of long-term follow-up, particularly in younger patients. Surgeons who are skilled in open aortic repair must not only be involved, but should take on a leadership role during the planning, deployment, and follow-up of these patients. Familiarity with all of the available devices expands treatment options. As more specific devices become available, and more follow-up is accrued, the role of endovascular stents will continue to grow.

Overview of Great Vessel Trauma

Traumatic injury to the aorta and the brachiocephalic branches are potentially lethal injuries. Specialized preoperative imaging and medical management can lead to better outcomes in this group of patients. In addition, improved surgical techniques for spinal cord protection have led to decreased morbidity in surgical candidates. TEVAR remains a promising technique; however, long-term data currently are not available.