Outcomes and survival in surgical treatment of descending thoracic aorta with acute dissection

Acute Type B Aortic Dissection Complicated With Spinal Cord Ischemia and Paraplegia Treated With Endovascular Scissor Technique

Spinal cord ischemia leading to paraplegia is a rare, life-limiting complication of acute type B aortic dissection. We report a case of spinal cord ischemia occurred in a young woman treated with endovascular scissor technique in urgent setting. The patient had an uneventful post-procedural course. After 4 months, computed tomography angiography confirmed false lumen reperfusion and major symptoms were regressed. In selected cases, this procedure is a tool to improve false lumen perfusion in type B dissections, and demonstrated to be helpful in our case of spinal cord ischaemia.

Towards biomechanics-based pre-procedural planning for thoracic endovascular aortic repair of aortic dissection

BACKGROUND AND OBJECTIVE

Although thoracic aortic endovascular repair (TEVAR) has shown promising outcomes in the treatment of patients with complicated type B aortic dissection, complications still occur after TEVAR that can lead to catastrophic events. Biomechanical interactions between the stent-graft (SG) and the local aortic tissue play a critical role in determining the outcome of TEVAR. Different SG design may cause different biomechanical responses in the treated aorta, but such information is not known at the time of pre-procedural planning. By developing patient-specific virtual stent-graft deployment tools, it is possible to analyse and compare the biomechanical impact of different SGs on the local aorta for individual patients.

METHODS

A finite element based virtual SG deployment model was employed in this study. Computational simulations were performed on a patient-specific model of type B aortic dissection, accounting for details of the SG design and the hyperelastic behaviour of the aortic wall. Based on the geometry reconstructed from the pre-TEVAR CTA scan, the patient-specific aortic dissection model was created and pre-stressed. Parametric models of three different SG products (SG1, SG2 and SG3) were built with two different lengths for each design. The SG models incorporated different stent and graft materials, stent strut patterns, and assembly approaches. Using our validated SG deployment simulation framework, virtual trials were performed on the patient-specific aortic dissection model using different SG products and varying SG lengths.

CONCLUSION

Simulation results for different SG products suggest that SG3 with a longer length (SG3-long) would be the most appropriate device for the individual patient. Compared to SG1-short (the SG deployed in the patient), SG3-long followed the true lumen tortuosity closely, resulted in a more uniform true lumen expansion and a significant reduction in peak stress in the distal landing zone. These simulation results are promising and demonstrate the feasibility of using the virtual SG deployment model to assist clinicians in pre-procedural planning.

Aortic dissection: results of the invasive treatment in France between 2012 and 2018 according to the French national database

BACKGROUND

To evaluate results of the invasive repair in the management of acute aortic dissection (AoD) in France.

METHODS

Patients admitted to hospital with acute AoD from 2012 to 2018 were identified. Patient demographics, severity score at admission, treatment strategy and in-hospital mortality were described. For patients undergoing intervention, perioperative complications rate was reported. A secondary analysis evaluating patients' outcome as regards of the annual caseload per center was conducted.

RESULTS

Overall, 14,706 patients with acute AoD were identified (male 64%, mean age 67, median modified Elixhauser score 5). The overall incidence increased during the study period (from 3.8 in 2012 to 4.4/100,000 in 2018) associated with a North-South gradient (respectively 3.6 vs. 4.7/100,000) and a winter peak; 45.5% (N.=6697) of patients received medical treatment alone. Among those with invasive repair, 6276 (78.3%) were defined as type A AoD (TAAD), whereas type B AoD (TBAD) accounted for 1733 patients (21.7%), of whom 1632 (94%) had TEVAR and 101 (6%) had other arterial procedures; 30-day mortality was respectively 18.9% in TAAD and 9.5% for TBAD. In high-volume centers (i.e. >20 AoD/year), a lower 3-month mortality of 22.3% was noted compared to 31.4% in the low-volume centres (P<0.001); 47% of patients reported ≥1 early major complication. TEVAR exhibited less complication (P<0.001) compared to other arterial reconstructions in TBAD.

CONCLUSIONS

The incidence of acute AoD increased in France over the period of the study and was associated with stable postoperative early mortality. Early postoperative mortality is significantly reduced in high-volume centers.

Hotspots and development frontiers of postoperative complications of AD: Bibliometric analysis - a review

The research on the postoperative complications of aortic dissection (AD) has received great attention from scholars all over the world, and the number of research articles in this field has consistently increased year after year. However, no bibliometric reports have been published yet to analyze the scientific output and the current situation in this field. The Bibliometrix R-package, VOSviewer, and CiteSpace software were used to conduct a bibliometric analysis of the hotspots and development frontiers of AD. A total of 1242 articles were retrieved. The USA, China, and Japan had the highest number of publications. The five keywords with the highest frequency were "analysis," "incidence," "acute type," "graft," and "risk factor." The results also indicated that the research in related fields had shifted from surgical treatment and utilizing experience to the evidence-based exploration of risk factors and the construction of prediction models to help better manage postoperative complications of AD. This is the first bibliometric analysis of global publications on the postoperative complications of AD. The current research hotspots focus on three areas: common postoperative complications of AD, exploration of the related risk factors, and management of complications. Future research could focus on identifying risk factors through meta-analysis and using a multicenter database for AD as well as building relevant models to predict the development of complications to better facilitate the clinical management of AD patients.

Open surgical replacement of the descending aorta: single-center experience

Background

This study presents a single center's experience and analyzes clinical outcomes following elective open surgical descending aortic replacement.

Methods

Between January 2000 and August 2019, 96 patients with mean age 64 years (range, 49.5-71 years) (62.5% (n=60) male) underwent elective descending aortic replacement due to aneurysm (n=60) or chronic dissection (n=36). Marfan syndrome was present in 12 patients (12.5%).

Results

In-hospital mortality rate was 3.1% (n= 3. 2 in the aneurysm group, 1 in the dissection group). New-onset renal insufficiency postoperatively with (creatinine ≥ 2.5 mg/dl) manifested in 10 patients (10.8%). One patient (1%) suffered from stroke, and paraplegia developed in 1 pts (1%). The median follow-up time was 7 years (IQR: 2.5-13 years). The 5- and 10-year survival rates were 70.8% and 50.7% respectively. We did not observe any early or late prosthetic graft infection. The Cox proportional hazards regression analysis identified age (HR: 1.044, 95% CI: 1.009-1.080, p-value: 0.014), diabetes (HR: 2.544, 95% CI: 1.009-6.413, p-value: 0.048), and chronic obstructive pulmonary disease (COPD) (HR: 2.259, 95% CI: 1.044-4.890, p-value: 0.039) as risk factors for late mortality.

Conclusions

This study showed that the elective open surgical replacement of the descending aorta can be achieved with excellent outcomes in terms of perioperative mortality and morbidity. Prosthetic graft is not a problem with open surgical descending aortic replacement, even in the long term.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12055-022-01443-x.

Aortic arch surgery for type B aortic dissection: How far should we go? The value of a hybrid approach

Traditionally, the management of type B aortic dissection has been the domain of the vascular surgeons. Timing and type of intervention still generate debate. We sought to review our early experience with the treatment of this condition based on a hybrid approach following an aortic multi-disciplinary team meeting involving close cooperation between cardiac surgeons, vascular surgeons, interventional radiologists, vascular anesthetists, and cardiac anesthetists. Four patients (age 41-56 years; 3 males; 1 female) with type B aortic dissection underwent aortic arch surgery through a hybrid approach: one elective procedure consisting of ascending aorta and hemi-arch replacement with debranching followed by thoracic endovascular aortic repair (TEVAR); one redo procedure requiring aortic arch replacement with hybrid frozen elephant trunk; two acute presentations (aortic arch replacement and debranching followed by TEVAR; AVR with ascending aorta, arch, and proximal descending thoracic aorta replacement with conventional elephant trunk and debranching). Deep hypothermic circulatory arrest was required in three patients. Despite respiratory complications and slightly prolonged postoperative course, all patients survived without onset of stroke, paraplegia, malperfusion, endoleak, or need for re-exploration. Follow-up remains satisfactory. Different factors may affect outcome following complex aortic procedures. Nevertheless, close cooperation between cardiac surgeons, vascular surgeons, and interventional radiologists may reduce potential for complications and address aspects that may not be completely within the domain of individual specialists.

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.

ARISE: First-In-Human Evaluation of a Novel Stent Graft to Treat Ascending Aortic Dissection

BACKGROUND

Operative mortality for type A aortic dissection is still 10-20% at centers of excellence. Additionally, 10-20% are not considered as viable candidates for open surgical repair and not offered life-saving emergency surgery. ARISE is a multicenter investigation evaluating the novel GORE® Ascending Stent Graft (ASG; Flagstaff, AZ).

OBJECTIVE

The purpose of this study is to assess early feasibility of using these investigational devices to treat ascending aortic dissection.

METHODS

This a prospective, multicenter, non-randomized, single-arm study that enrolls patients at high surgical risk with appropriate anatomical requirements based on computed tomography imaging at 7 of 9 US sites. Devices are delivered transfemorally under fluoroscopic guidance. Primary endpoint is all-cause mortality at 30 days. Secondary endpoints include major adverse cardiovascular and cerebrovascular events (MACCE) at 30 days, 6 months, and 12 months.

RESULTS

Nineteen patients were enrolled with a mean age of 75.7 years (range 47-91) and 11 (57.9%) were female. Ten (52.6%) had DeBakey type I disease, and the rest were type II. Sixteen (84.2%) of the patients were acute. Patients were treated with safe access, (7/19 (36.8%) percutaneous, 10/19 (52.6%) transfemoral, 2/19 (10.5%) iliac conduit), delivery, and deployment completed in all cases. Median procedure time was 154 mins (range 52-392) and median contrast used was 111 mL (range 75-200). MACCE at 30 days occurred in 5 patients including mortality 3/19 (15.8%), disabling stroke in 1/19 (5.3%), and myocardial infarction in 1/19 (5.3%).

CONCLUSION

Results from the ARISE early feasibility study of a specific ascending stent graft device to treat ascending aortic dissection are promising.

The effect of beta-blockers on hemodynamic parameters in patient-specific blood flow simulations of type-B aortic dissection: a virtual study

Aortic dissection (AD) is one of the fatal and complex conditions. Since there is a lack of a specific treatment guideline for type-B AD, a better understanding of patient-specific hemodynamics and therapy outcomes can potentially control the progression of the disease and aid in the clinical decision-making process. In this work, a patient-specific geometry of type-B AD is reconstructed from computed tomography images, and a numerical simulation using personalised computational fluid dynamics (CFD) with three-element Windkessel model boundary condition at each outlet is implemented. According to the physiological response of beta-blockers to the reduction of left ventricular contractions, three case studies with different heart rates are created. Several hemodynamic features, including time-averaged wall shear stress (TAWSS), highly oscillatory, low magnitude shear (HOLMES), and flow pattern are investigated and compared between each case. Results show that decreasing TAWSS, which is caused by the reduction of the velocity gradient, prevents vessel wall at entry tear from rupture. Additionally, with the increase in HOLMES value at distal false lumen, calcification and plaque formation in the moderate and regular-heart rate cases are successfully controlled. This work demonstrates how CFD methods with non-invasive hemodynamic metrics can be developed to predict the hemodynamic changes before medication or other invasive operations. These consequences can be a powerful framework for clinicians and surgical communities to improve their diagnostic and pre-procedural planning.

A multicenter study of emergency endovascular repair of the thoracic aorta: Indications and outcomes

OBJECTIVE

Endovascular techniques have become an essential tool for the treatment of descending thoracic aortic disease (thoracic endovascular aneurysm repair [TEVAR]). The aim is to analyze the indications and outcomes of emergency TEVAR at national level in relation to elective surgery.

STUDY DESIGN AND SCOPE

A retrospective multicenter registry of patients with descending thoracic aortic disease treated on an emergency basis using endovascular techniques between 2012-2016, in 11 clinical units.

PATIENTS, INCLUSION CRITERIA

1) Ruptured descending thoracic aortic aneurysms (RTAA); 2) Blunt traumatic thoracic aortic injury (TAI); and 3) Complicated acute type B aortic dissections (TBADc).

PRIMARY VARIABLES

Patient mortality, survival and reoperation rate.

SECONDARY VARIABLES

Demographic data, cardiovascular risk factors, specific data by indication, technical resources and postoperative complications.

RESULTS

A total of 135 urgent TEVARs were included (111 men, mean age 60.4 ± 16.3 years): 43 ruptured thoracic aortic aneurysms (31.9%), 54 type B dissections (40%) and 32 traumatic aortic injuries (23.7%), and other etiologies 4.4%. The overall mortality rate at 30 days was 18.5%, and proved higher in the RTAA group (27.9%). The mean actuarial survival rate was 67 ± 6% at 5 years. The postoperative stroke rate was 5.2%, and the paraplegia rate was 5.9%. Aortic reoperations proved necessary in 12 patients (9%).

CONCLUSIONS

Emergency descending thoracic aortic diseases can be treated by endovascular techniques with optimal results and low morbidity and mortality - though the figures are slightly higher than in elective cases. This registry provides, for the first time, real information on the daily clinical practice of emergency TEVAR in Spain.

Wrapping of ascending aortic aneurysm with supra-aortic debranching and endovascular repair for aortic arch aneurysm and ruptured descending thoracic aortic aneurysm

We report a case of a hybrid surgical treatment of a 71-year-old fragile female with severe chronic obstructive pulmonary disease with a 5-year history of progressive back pain and diagnosis of descending thoracic aorta aneurysm (DTAA), but refused operation at first. Since the patient presented with an acute expanding painful pulsatile mass due to a ruptured DTAA contained by the subcutaneous tissue and had a high-risk surgical profile, we agreed that the simplest urgent operation should be performed. Cardiopulmonary bypass with or without deep hypothermic circulatory arrest was ruled out as an option. The initial approach would be permanent bypasses to the supra-aortic trunks and endovascular repair of the ruptured DTAA, but we ran into a problem: the absence of suitable diameter in the ascending aorta to land the prosthesis-zone 0. To overcome this obstacle, we opted to perform a diameter reduction of the ascending aorta by wrapping it with a Dacron tube to create a neck where we could land the endovascular prosthesis. Following this step bypasses from the proximal ascending aorta to the brachiocephalic artery, left common carotid artery and left subclavian artery were created. Since we gained ground to act in zone 0, the first endoprosthesis was landed in the wrapped zone and the aortic arch-from zone 0 to zone 3. The second and third endoprostheses covered the ruptured DTAA above the celiac trunk-zones 4 and 5. Good positioning of the endoprostheses was achieved and we attained procedural success.

A multicenter study of emergency endovascular repair of the thoracic aorta: indications and outcomes

OBJECTIVE

Endovascular techniques have become an essential tool for the treatment of descending thoracic aortic disease (thoracic endovascular aneurysm repair [TEVAR]). The aim is to analyze the indications and outcomes of emergency TEVAR at national level in relation to elective surgery.

STUDY DESIGN AND SCOPE

A retrospective multicenter registry of patients with descending thoracic aortic disease treated on an emergency basis using endovascular techniques between 2012-2016, in 11 clinical units.

PATIENTS, INCLUSION CRITERIA

1) Ruptured descending thoracic aortic aneurysms; 2) Blunt traumatic thoracic aortic injury; and 3) Complicated acute type B aortic dissections (TBADc).

PRIMARY VARIABLES

Patient mortality, survival and reoperation rate.

SECONDARY VARIABLES

Demographic data, cardiovascular risk factors, specific data by indication, technical resources and postoperative complications.

RESULTS

A total of 135 urgent TEVARs were included (111 men, mean age 60.4 ± 16.3 years): 43 ruptured thoracic aortic aneurysms (31.9%), 54 type B dissections (40%) and 32 traumatic aortic injuries (23.7%), and other etiologies 4.4%. The overall mortality rate at 30 days was 18.5%, and proved higher in the ruptured descending thoracic aortic aneurysms group (27.9%). The mean actuarial survival rate was 67± 6% at 5 years. The postoperative stroke rate was 5.2%, and the paraplegia rate was 5.9%. Aortic reoperations proved necessary in 12 patients (9%).

CONCLUSIONS

Emergency descending thoracic aortic diseases can be treated by endovascular techniques with optimal results and low morbidity and mortality - though the figures are slightly higher than in elective cases. This registry provides, for the first time, real information on the daily clinical practice of emergency TEVAR in Spain.

Systematic review and meta-analysis of acute type B thoracic aortic dissection, open, or endovascular repair

OBJECTIVE

The purpose of this study was to compare perioperative and mortality outcomes of endovascular aortic repair against open repair in acute type B thoracic aortic dissection.

METHODS

A comprehensive search was undertaken among the four major databases (PubMed, Embase, Scopus, and Ovid) to identify all published data comparing open vs endovascular repair in management of acute type B aortic dissection. Databases where evaluated and assessed to July 2017. The 95% confidence intervals were analyzed from the extracted data using relevant statistical methods.

RESULTS

Overall, 18,193 patients were found in a combination of nine studies. Patients undergoing open repair were younger (mean, 61.3 ± 9.3 years vs 66.6 ± 12.5 years; P < .00001). Postoperative stroke and paraplegia were similar in both groups (P = .71 and P = .81 respectively); however, the rate of all neurologic complications were more common in the traditional open repair group (6.9% vs 4.8%; P = .006). The all-cause operative and 1-year death was reported as higher in the open repair group (18.6% vs 7.4% [P < .0001] and 24.3% vs 14.3% [P < .0001], respectively); however, at 5 years this rate is almost similar between both groups (46.7% vs 49.7%; P = .21). At 1 year, the rate of reintervention was reported to be higher in endovascular repair group of patients (15.4% vs 5.5%; P = .004).

CONCLUSIONS

This study concludes that endovascular repair, in the setting of acute type B thoracic aortic dissection, provides an early surgical benefit; however, this finding has not yet been supported by long-term data. There seems to be a benefit with respect to all-neurologic events in favor of endovascular repair. Long-term comparative data and studies are required to give a better understanding of these two approaches.

Type B aortic dissection: new perspectives

Background

Stanford type B aortic dissection is one of the aortic catastrophes with a high mortality and morbidity that needs immediate or delayed treatment, either surgically or endovascularly. This comprehensive review article addresses the current status of open, endovascular and hybrid treatment options for type B aortic dissections with the focus on new therapeutic perspectives.

Methods

Evaluation of currently available evidence based on randomized and registry data and personal experience.

Results

All type B dissections require prompt medical treatment to prevent aortic rupture. Acute complicated dissections are nowadays treated by endografting to reroute blood flow into the true lumen and promote false lumen thrombosis and future aortic remodeling. In acute uncomplicated situations the position of endografting is less clear and should be further delineated; however, on the long run also in these situations endografting might be protective for future aortic catastrophes in certain patient categories. In the chronic dissection with aneurysm formation of the descending thoracic and/or thoracoabdominal aorta, especially in connective tissue disorders, open surgery offers nowadays the best immediate results with long durability. Thoracic endografting plays only a minor role in these circumstances but branched and fenestrated endografting are very promising techniques. Hybrid techniques can offer the solution for high risk patients that are not suitable for open surgery.

Conclusions

Emergent thoracic endografting is the golden standard for all complicated type B dissections while uncomplicated patients with high-risk features might benefit from endovascular repair. Open surgery is limited for chronic post dissection aneurysms. Aortic surveillance is of paramount importance in all situations.

Conservative management versus endovascular or open surgery in the spectrum of type B aortic dissection

Background

Type B aortic dissection is a life-threatening acute aortic condition often with acute ischemic signs or symptoms. With initial management focusing on alleviating malperfusion and pain, and avoiding propagation of dissection or rupture both systolic blood and pulse pressure should be reduced initially by an aggressive medical approach. In the setting of persistent signs of complications endovascular strategies have replaced open surgery and led to a fourfold increase in early survival and better long-term outcomes.

Methods

An electronic health database search was performed on articles published between January 2006 and July 2017. Publications were included in this review if (I) the index aortic pathology was type B aortic (distal) dissection; (II) when medical management, open surgical replacement or thoracic endovascular aortic repair were among those options; (III) when at least one of all basic outcome criteria such as survival, spinal cord ischemia and cerebrovascular accident was reported; (IV) when ≥15 serial patients were included. A total of 62 studies were eligible and analysed.

Results

Our manuscript has summarized data collected over 12 years on management specific outcomes in the setting of distal aortic dissection and provides an up-to-date interpretation of the published evidence. For complicated cases, treated acutely, the 30-day or in-hospital mortality was 7.3% when managed by endovascular means, whereas the pooled rate for 30-day or in-hospital mortality was 19.0% when subjected to open repair. For acute uncomplicated type B dissection usually treated with blood pressure lowering medications, the pooled 30-day or in-hospital mortality rate was 2.4%. Survival rates at 5 years averaged at 60% (40% mortality). Freedom from any aortic event ranged from 34.0% to 83.9%, underlining an inherent risk of progression and late complications. For chronic complicated type B dissection, the rates of stroke, paraplegia and operative mortality following endovascular repair ranged from 5% to 13%, 2% to 13% and 2 to 13%, respectively, while 5-year survival rates after open repair ranged from 60% to 90%. In chronic uncomplicated type B dissection almost 90% of patients survive initial hospitalization and were subjected to medical management with a 5-year survival of 50-80%. However, up to 20-55% of medically treated patients develop aneurysmal degeneration after 5 years with an unknown risk of rupture.

Conclusions

Currently, the less invasive strategy of endovascular repair (as compared to open surgery) provides improved 30-day or in-hospital survival in the setting of complicated acute type B aortic dissection and may seek broad application. Open surgical aortic reconstruction should be left to experienced aortic centres if endovascular management is not an option.

Total Endovascular Treatment of Acute Non-A-non-B Dissection Complicated by Visceral Malperfusion without Primary Entry Tear Coverage

Management of visceral ischemia due to non-A, non-B dissection is extremely challenging due to the position of the primary entry tear at the level of the brachiocephalic vessels. We report on a patient who was admitted for a complicated non-A, non-B-type dissection with visceral and leg ischemia. A covered stent graft was implanted below the primary entry tear to redirect the flow in the true lumen, associated with stents implantation in the visceral arteries, to treat the dissection's static component. The patient did well, without need for bowel resection visceral or late stent restenosis. Stent-graft implantation below the primary entry tear in cases of visceral ischemia due to non-A, non-B dissection seems feasible.

Type B Aortic Dissections: Current Guidelines for Treatment

Stanford type B aortic dissections (TBADs) involve the descending aorta and can present with complications, including malperfusion syndrome or aortic rupture, which are associated with significant morbidity and mortality if left untreated. Clinical diagnosis is straightforward, typically confirmed using CT angiography. Treatment begins with immediate anti-impulse medical therapy. Acute TBAD with complications should be repaired with emergent thoracic endovascular aortic repair (TEVAR). Uncomplicated TBAD with high-risk features should undergo TEVAR in the subacute phase. Open surgical repair is seldom required and reserved only for select cases. It is critical to follow these patients clinically and radiographically in the outpatient setting.

Frozen Elephant Trunk and Antegrade Visceral Debranching in the Surgical Treatment of Type B Aortic Dissection: An Alternative Method

Intervention is inevitable in complicated Type B aortic dissections. Classical surgical procedures and endovascular interventions are far from ideal treatments due to their high risk of periprocedural complications and mortality. There is often a need for alternative method in cases of difficult anatomy. We present the combined use of frozen elephant trunk and antegrade visceral debranching methods in the treatment of a 54-year-old male patient with complicated Type B aortic dissection.

TEVAR for ruptured descending thoracic aortic aneurysm: case report

A ruptured descending thoracic aortic aneurysm (rDTAA) is a life-threatening condition associated with high morbidity and mortality. Endovascular treatment for rDTAA promotes effective aneurysm exclusion with a minimally invasive approach. The authors report a case of a 76-year-old man with hemodynamically unstable 9-cm-diameter rDTAA treated with emergency thoracic endovascular aortic repair (TEVAR).

Aortic dissection

Aortic dissection is a life-threatening condition caused by a tear in the intimal layer of the aorta or bleeding within the aortic wall, resulting in the separation (dissection) of the layers of the aortic wall. Aortic dissection is most common in those 65-75 years of age, with an incidence of 35 cases per 100,000 people per year in this population. Other risk factors include hypertension, dyslipidaemia and genetic disorders that involve the connective tissue, such as Marfan syndrome. Swift diagnostic confirmation and adequate treatment are crucial in managing affected patients. Contemporary management is multidisciplinary and includes serial non-invasive imaging, biomarker testing and genetic risk profiling for aortopathy. The choice of approach for repairing or replacing the damaged region of the aorta depends on the severity and the location of the dissection and the risks of complication from surgery. Open surgical repair is most commonly used for dissections involving the ascending aorta and the aortic arch, whereas minimally invasive endovascular intervention is appropriate for descending aorta dissections that are complicated by rupture, malperfusion, ongoing pain, hypotension or imaging features of high risk. Recent advances in the understanding of the underlying pathophysiology of aortic dissection have led to more patients being considered at substantial risk of complications and, therefore, in need of endovascular intervention rather than only medical or surgical intervention.

Update in the management of type B aortic dissection

Stanford type B aortic dissection (TBAD) is a life-threatening aortic disease. The initial management goal is to prevent aortic rupture, propagation of the dissection, and symptoms by reducing the heart rate and blood pressure. Uncomplicated TBAD patients require prompt medical management to prevent aortic dilatation or rupture during subsequent follow-up. Complicated TBAD patients require immediate invasive management to prevent death or injury caused by rupture or malperfusion. Recent developments in diagnosis and management have reduced mortality related to TBAD considerably. In particular, the introduction of thoracic stent-grafts has shifted the management from surgical to endovascular repair, contributing to a fourfold increase in early survival in complicated TBAD. Furthermore, endovascular repair is now considered in some uncomplicated TBAD patients in addition to optimal medical therapy. For more challenging aortic dissection patients with involvement of the aortic arch, hybrid approaches, combining open and endovascular repair, have had promising results. Regardless of the chosen management strategy, strict antihypertensive control should be administered to all TBAD patients in addition to close imaging surveillance. Future developments in stent-graft design, medical therapy, surgical and hybrid techniques, imaging, and genetic screening may improve the outcomes of TBAD patients even further. We present a comprehensive review of the recommended management strategy based on current evidence in the literature.

Current management of acute type B aortic dissection

Acute type B aortic dissection (TBAD) occurs as a result of an intimal tear within the proximal thoracic aorta. Patients are typically managed acutely with aggressive antihypertensive therapy. Surgical repair is reserved for those who develop complications such as rupture or malperfusion. The surgical management of acute TBAD has changed considerably in the last decade secondary to the advent of thoracic stent grafting. Thoracic endovascular aortic repair (TEVAR) has improved early mortality and morbidity rates for patients presenting with complicated TBAD. The role of TEVAR in patients presenting with acute and subacute uncomplicated TBAD is less clear. TEVAR has been associated with increased late survival and better aortic remodeling, with low perioperative morbidity in selected patients. Recent literature suggests certain radiographic criteria may be used to predict patients developing late aortic events who would benefit from early TEVAR. The purpose of this article is to review the contemporary management of acute TBAD, discuss controversies in management and evaluate the latest research findings.

Endovascular management of rupture in acute type B aortic dissections

OBJECTIVE

Reports of thoracic endovascular aortic repair (TEVAR) for complicated acute type B aortic dissection (ABAD) bring together a large range of clinical presentations. With a 30 day mortality of 50% when managed with open surgery, rupture is the most devastating complication of ABAD. This study investigated the outcome of TEVAR for ABAD complicated by rupture (r-ABAD) to assess the results of this particularly critical subgroup.

METHODS

A review of consecutive TEVAR for r-ABAD in two tertiary referral centers was performed using a prospectively maintained database.

RESULTS

Between 2000 and 2013, 24 patients (mean age 71 years; 14 males) underwent TEVAR for r-ABAD. Sixteen (67%) were in shock (Systolic blood pressure <80 mmHg) before surgery. Seven patients had coverage of the left subclavian artery, of whom four had partial arch debranching procedures via cervical access concomitant with TEVAR. Median length of aortic coverage was 150 mm, median proximal oversizing was 13.3% (range 6.2-33.3%). Technical success was achieved in 100%. There were four in hospital deaths (16%). Two patients (8%) had paraplegia, but neither stroke nor renal insufficiency requiring dialysis occurred. During a mean follow up of 28 months, there was one aortic dissection related death and eight patients (40% of the surviving patients) required re-intervention. All re-interventions were managed endovascularly. At last follow up CT scan, eight patients (40%) had complete remodeling of the aortic wall.

CONCLUSION

With 16% in hospital mortality and 8% early major complications, this study confirms the feasibility of TEVAR for r-ABAD with a lower peri-operative morbidity and mortality rate compared with open surgery. Given the high rate of re-intervention, close follow up is required in surviving patients.

Outcomes of open surgical repair of descending thoracic aortic disease

Background

To determine the predictors of clinical outcomes following surgical descending thoracic aortic (DTA) repair.

Methods

We identified 103 patients (23 females; mean age, 64.1±12.3 years) who underwent DTA replacement from 1999 to 2011 using either deep hypothermic circulatory arrest (44%) or partial cardiopulmonary bypass (CPB, 56%).

Results

The early mortality rate was 4.9% (n=5). Early major complications occurred in 21 patients (20.3%), which included newly required hemodialysis (9.7%), low cardiac output syndrome (6.8%), pneumonia (7.8%), stroke (6.8%), and multi-organ failure (3.9%). None experienced paraplegia. During a median follow-up of 56.3 months (inter-quartile range, 23.1 to 85.1 months), there were 17 late deaths and one aortic reoperation. Overall survival at 5 and 10 years was 80.9%±4.3% and 71.7%±5.9%, respectively. Reoperation-free survival at 5 and 10 years was 77.3%±4.8% and 70.2%±5.8%. Multivariable analysis revealed that age (hazard ratio [HR], 1.10; 95% confidence interval [CI], 1.05 to 1.15; p<0.001) and left ventricle (LV) function (HR, 0.88; 95% CI, 0.82 to 0.96; p<0.003) were significant and independent predictors of long-term mortality. CPB strategy, however, was not significantly related to mortality (p=0.49).

Conclusion

Surgical DTA repair was practicable in terms of acceptable perioperative mortality/morbidity as well as favorable long-term survival. Age and LV function were risk factors for long-term mortality, irrespective of the CPB strategy.

Case Report and Review of Literature: Late Retrograde Type A Aortic Dissection With Rupture after Repair of Type B Aortic Dissection with a GORE TAG Endovascular Prosthesis

Acute aortic dissection is the most common catastrophic condition of the aorta. Treatment options include open surgery and thoracic endovascular aortic reconstruction (TEVAR). We present a late Type A dissection as a complication of the management of descending aortic dissections with TEVAR and a review of the literature. TEVAR of the thoracic aorta is a viable treatment option for the management of complicated descending thoracic aortic dissections. Careful patient selection is necessary as medical therapy successfully treats the majority of uncomplicated Type B dissections. TEVAR should be reserved for patients with complicated Type B dissections or those who fail nonoperative management. Close postoperative monitoring is necessary when TEVAR is performed and should be accompanied by lifelong surveillance. A high level of suspicion is important to identify retrograde Type A dissections in these patients given its rarity and the ambiguity of its clinical presentation.

Emergency endovascular stent grafting in acute complicated type B dissection

OBJECTIVE

The objective of this study was to assess midterm results of emergency endovascular stent grafting for patients with life-threatening complications of acute type B aortic dissection.

METHODS

Between March 1999 and November 2011, 110 patients (86 men, 24 women) with complications of acute type B aortic dissection (mean age, 61 years; range, 19-87 years) were treated with thoracic endovascular aortic repair for malperfusion (55.5%) or aortic rupture (53.6%) in five major European referral centers and one U.S. referral center. Additional comorbidities included hypertension in 90 patients (82%), diabetes in 14 patients (13%), and chronic obstructive pulmonary disease in six patients (6%). Eleven patients (10%) had undergone previous aortic surgery.

RESULTS

Overall hospital mortality was 12% (n = 13), with 14 late deaths after hospital discharge. In-hospital complications occurred in 32 patients (36%); 10 patients developed postoperative renal failure, five patients experienced new permanent neurologic symptoms, and six patients (5.4%) experienced retrograde type A aortic dissection. Furthermore, nine patients (8%) developed an early type I endoleak. Actuarial survival at 1 and 5 years was 85% and 73%, respectively. Postprocedural computed tomography angiography showed complete or partial thrombosis of the false lumen at the stent graft level in 61% and 23% of all patients, respectively. Freedom from treatment failure according to the Stanford classification was 82%, 75%, and 59% at 1, 3, and 5 years.

CONCLUSIONS

Endovascular repair of complicated acute type B aortic dissection is proven to be a technically feasible and effective treatment modality in this relatively difficult patient cohort. Short-term and midterm results are persuasive; however, the long-term efficacy needs to be further evaluated.

Management of complicated and uncomplicated acute type B dissection. A systematic review and meta-analysis

BACKGROUND

The management of acute type B dissection represents a clinical challenge. We undertook a systematic review of the available literature regarding medical, surgical and endovascular treatments of acute type B aortic dissection and combined the eligible studies into a meta-analysis.

METHODS

An extensive electronic health database search was performed on all articles published from January 2006 up to November 2013 describing the management of acute type B aortic dissection. Studies including less than 15 patients were excluded.

RESULTS

ACUTE COMPLICATED TYPE B DISSECTION: overall, 2,531 patients were treated with endovascular repair (TEVAR) and the pooled rate for 30-day/in-hospital mortality was 7.3%. The pooled estimates for cerebrovascular events, spinal cord ischemia (SCI) and total neurologic events were 3.9%, 3.1% and 7.3%, respectively. A total of 1,276 patients underwent open surgical repair and the pooled rate for 30-day/in-hospital mortality was 19.0%. The pooled rate for cerebrovascular events was 6.8%, for SCI 3.3% and for total neurologic complications 9.8%. Acute uncomplicated type B dissection: outcome of 2,347 patients who underwent conservative medical management were analyzed. The pooled 30-day/in-hospital mortality rate was 2.4%. The pooled rate for cerebrovascular events was 1%, for SCI 0.8% and for overall neurologic complications 2%.

CONCLUSIONS

Endovascular repair provides a superior 30-day/in-hospital survival for acute complicated type B aortic dissection compared to surgical aortic reconstruction. However, open repair still has a significant role as endovascular repair is not applicable in all patients and there remains concerns regarding the durability of this technique. TEVAR seems to have a more favorable outcome regarding aortic remodeling and the aortic-specific survival rate when compared with medical therapy alone. Randomized controlled trials focusing on the prognostic factors of early and late complications in uncomplicated type B dissections are needed.

Best surgical option for arch extension of type B dissection: the endovascular approach

Despite advances in surgical techniques and postoperative management, the in-hospital mortality rate for patients undergoing conventional open surgical repair for type B dissections is still significant. In light of this, the less invasive surgical procedure for acute type B aortic dissections, defined as thoracic endovascular aortic repair (TEVAR), was developed. Despite some controversy, the use of TEVAR for the management of type B aortic dissections has become commonplace. Generally, the main entry tear in type B aortic dissection is located in the vicinity of the orifice of the left subclavian artery (LSA). The proximal landing zone in the aortic arch must be secured as long as the aim of TEVAR for type B dissection is primary entry closure. This requires hybrid surgery that includes the use of open surgical procedures, such as debranching for revascularization of cervical branches. Despite the presence of challenging anatomic conditions in the aortic arch, hybrid repair has evolved as an increasingly viable alternative, and promising early and long-term results have been reported. As the next step, fenestrated and branched TEVAR techniques have recently been reported with satisfactory early results. In the coming years, there will be intense competition to develop the devices themselves, improve delivery systems, and supplement devices with auxiliary functions. Thus there is high expectations for the next generation and how they will improve and advance treatment methods of TEVAR for type B aortic dissections.

National trends in utilization, mortality, and survival after repair of type B aortic dissection in the Medicare population

OBJECTIVE

The application of thoracic endovascular aortic repair (TEVAR) has changed treatment paradigms for thoracic aortic disease. We sought to better define specific treatment patterns and outcomes for type B aortic dissection treated with TEVAR or open surgical repair (OSR).

METHODS

Medicare patients undergoing type B thoracic aortic dissection repair (2000-2010) were identified by use of a validated International Classification of Diseases, Ninth Revision diagnostic and procedural code-based algorithm. Trends in utilization were analyzed by procedure type (OSR vs TEVAR), and patterns in patient characteristics and outcomes were examined.

RESULTS

Total thoracic aortic dissection repairs increased by 21% between 2000 and 2010 (2.5 to 3 per 100,000 Medicare patients; P = .001). A concomitant increase in TEVAR was seen during the same interval (0.03 to 0.8 per 100,000; P < .001). By 2010, TEVAR represented 27% of all repairs. TEVAR patients had higher rates of comorbid congestive heart failure (12% vs 9%; P < .001), chronic obstructive pulmonary disease (17% vs 10%; P < .001), diabetes (8% vs 5%; P < .001), and chronic renal failure (8% vs 3%; P < .001) compared with OSR patients. For all repairs, patient comorbidity burden increased over time (mean Charlson comorbidity score of 0.79 in 2000, 1.10 in 2010; P = .04). During this same interval, in-hospital mortality rates declined from 47% to 23% (P < .001), a trend seen in both TEVAR and OSR patients. Whereas in-hospital mortality rates and 3-year survival were similar between patients selected for TEVAR and OSR, there was a trend toward women having slightly lower 3-year survival after TEVAR (60% women vs 63% men; P = .07).

CONCLUSIONS

Surgical treatment of type B aortic dissection has increased over time, reflecting an increase in the utilization of TEVAR. Overall, type B dissection repairs are currently performed at lower mortality risk in patients with more comorbidities.

Endovascular repair of thoracic and abdominal aortic ruptures: a single-center experience

PURPOSE

We aimed to present our preliminary single-center experience of the endovascular management of thoracic and abdominal aortic ruptures.

MATERIALS AND METHODS

Between September 2010 and May 2012, 11 consecutive patients (nine males, two females; age range, 26-80 years) with thoracic and abdominal aortic ruptures underwent endovascular repair in our unit. Thoracoabdominal computed tomography (CT) angiography was performed for diagnosis and follow-up. Patients were selected for endovascular repair by a cardiovascular surgeon, anesthesiologist, and interventional radiologist. All repairs were performed using commercially available stent-grafts. The patients were followed up with CT angiography before discharge, at six months, and yearly thereafter.

RESULTS

Three patients died by day 30. One patient died due to an unsuccessful procedure and hemodynamic instability; two patients died because of comorbidities. The other eight patients were followed for six to 24 months after the procedure. No endoleaks or late ruptures were observed during the follow-up period. The patient with iatrogenic thoracic aortic rupture developed paraplegia after the procedure.

CONCLUSION

Reduced mortality due to aortic rupture has been reported with the expanding use of endovascular repair. Reports of small centers are important because of the rarity of these pathologies, and because transferring patients with aortic rupture to a referral center is not usually possible.

TEVAR for type B aortic dissection in Japan

TEVAR is a new strategy for treating both acute and chronic type B aortic dissection. The JSC guidelines classify TEVAR as a Class I recommendation for cases of complicated acute type B dissection and a Class IIa recommendation for cases of chronic type B aortic dissection. While TEVAR has been primarily applied to treat complicated acute type B aortic dissection in Europe and the USA, the procedure remains an off-label treatment strategy for aortic dissection in Japan. The current state of TEVAR for type B aortic dissection in Japan from 2001 to 2011 is estimated in the annual reports of the Japanese Association for Thoracic Surgery. The number of acute type B aortic dissection patients treated with transluminal stent grafting increased rapidly after 2008, from 10 cases in 2001 to 76 cases in 2010. Meanwhile, the number acute type B aortic dissection patients treated with any type of surgery has increased gradually, from 100 cases in 2001 to 194 cases in 2009. The number of chronic type B aortic dissection patients treated with transluminal stent grafting increased abruptly in 2010, reaching 346 cases, which accounted for one-third of all surgical procedures for chronic type B aortic dissection. Furthermore, the number of open surgeries for chronic type B aortic dissection has also increased gradually, from 401 cases in 2001 to 947 cases in 2011. At present, open surgery, TEVAR and hybrid procedures are available to treat patients with type B aortic dissection. The use of a multidisciplinary team approach is mandatory when selecting the appropriate surgical strategy.

Five-year results for endovascular repair of acute complicated type B aortic dissection

INTRODUCTION

Despite a current lack of U.S. Food and Drug Administration approval for the indication, thoracic endovascular aortic repair (TEVAR) has replaced open surgical management for acute complicated type B aortic dissection due to promising short- and midterm data. However, long-term results, with a view toward durability and need for secondary procedures, are limited. As such, the objective of the present study is to report long-term outcomes of TEVAR for acute (≤ 2 weeks from symptom onset) complicated type B dissection.

METHODS

Between July 2005 and September 2012, 50 consecutive patients underwent TEVAR for management of acute complicated type B dissection at a single referral institution. Patient records were retrospectively reviewed from a prospectively maintained clinical database.

RESULTS

Indications for intervention included rupture in 10 (20%), malperfusion in 24 (48%), and/or refractory pain/impending rupture in 17 (34%). One patient (2%) had both rupture and malperfusion indications. Ten (20%) patients required one or more adjunctive procedures, in addition to TEVAR, to treat malperfusion syndromes. In-hospital and 30-day rates of death were both 0%; 30-day/in-hospital rates of stroke, permanent paraplegia/paraparesis, and new-onset dialysis were 2% (n = 1), 2% (n = 1), and 4% (n = 2), respectively. Median follow-up was 33.8 months [interquartile range, 12.3-56.6 months]. Overall survival at 5 and 7 years was 84%, with no deaths attributable to aortic pathology. Thirteen (26%) patients required a total of 17 reinterventions over the study period for type I endoleak (n = 5), metachronous aortic pathology (n = 5), persistent false lumen pressurization via distal fenestrations (n = 4), type II endoleak (n = 2), or retrograde acute type A aortic dissection (n = 1). Median time to first reintervention was 4.5 months (range, 0 days-40.3 months). Of the 17 total reinterventions, six (35%) were performed using open techniques and 11 (65%) with endovascular or hybrid methods; there was no difference in survival between patients who did or did not require reintervention.

CONCLUSIONS

This study confirms the excellent short-term outcomes of TEVAR for acute complicated type B dissection and demonstrates the results to be durable and sustained over long-term follow-up. Although aortic reinterventions were required in one-quarter of patients, no aortic-related deaths were observed. These data support the use of TEVAR for acute complicated type B aortic dissection but also highlight the importance of life-long aortic surveillance by an experienced aortic referral center in order to identify and treat complications of the underlying disease process and treatment, as well as new aortic pathologies, as they arise.