Endovascular repair or medical treatment of acute type B aortic dissection? A comparison

Effect of False Lumen Occlusion Treatment With AFX VELATM, Candy-Plug Technique for Chronic Aortic Dissection

INTRODUCTION

We sought to examine midterm results and remodeling effect of false-lumen occlusion treatment using AFX VELA in case of chronic dissection repair.

MATERIAL AND METHODS

From June 2019 to May 2022, we performed false lumen occlusion treatment using a modified Candy-Plug technique with AFX VELA on 8 chronic aortic dissection patients with a patent false lumen. We collected operative data, short-term clinical outcomes, mid-term clinical outcomes and imaging test results. We conducted follow-up examinations at postoperative, 6-month and 1-, 2- and 3-year intervals, including contrast-enhanced computed tomography to evaluate the diameter, false lumen thrombosis and any events.

RESULTS

The average time from the symptom onset to the thoracic endovascular repair was 81.5 (35-155) months. The aorta showed aneurysmal dilation with an average maximum short-axis diameter of 58.9 (41-91) mm. Two cases needed emergency surgery due to rupture and impending rupture. There were no postoperative deaths. Complete thrombosis within the false lumen was achieved in 6 cases (75%), but 2 cases had incomplete thrombosis, requiring additional treatment. The mean maximum diameter showed a significant decrease at 6 months, 1 year and 2 years postoperatively compared to preoperative measurements (P < .05).

CONCLUSION

We showed the results of false lumen occlusion treatment using the AFX VELA cuff. We observed favorable clinical outcomes and remodeling effects. While the long-term durability and efficacy of this technique in aortic remodeling will need to be monitored with further observation, the use of this cuff is considered a reliable approach to false lumen occlusion treatment.

Midterm Results of Thoracic Endovascular Aortic Repair with Reentry Closure for Chronic Type B Aortic Dissection with Aneurysmal Dilatation

Objectives: This study aims to discuss the midterm results of thoracic endovascular aortic repair (TEVAR) with reentry closure for chronic type B aortic dissection (CTBAD). Materials and Methods: This retrospective study analyzed 13 patients with CTBAD who underwent TEVAR with reentry closure between July 2014 and December 2020. We evaluated the false lumen (FL) cross-sectional area using computed tomography images of the descending aorta at the level of the bronchial bifurcation, Valsalva sinus, celiac artery, and infrarenal abdominal aorta pre- and postoperation. The study endpoints were technical and clinical success rates, freedom from additional aortic reintervention or surgery, and survival. Results: Technical success was obtained in 12 patients (92.3%) with no hospital mortality and neurological complications. The postoperative observation period was 49.2±21.5 months. The clinical success rate was 76.9% (10 cases), and a postoperative reduction of the FL cross-sectional area was obtained in 53.8% of patients. The 5-year overall survival rate was 64.8% with no aortic-related deaths while the 5-year freedom from additional aortic surgery rate was 66.7%. Conclusions: TEVAR with reentry closure suggests preventing FL dilatation or rupture in CTBAD, but the revision of our devices and further research with more patients and longer follow-up periods are required.

MANAGEMENT OF LEFT SUBCLAVIAN ARTERY IN TYPE-B AORTIC DISSECTION TREATED WITH THORACIC ENDOVASCULAR AORTA REPAIR

OBJECTIVE

Thoracic endovascular aortic repair (TEVAR) has been the favored approach for the treatment of type B aortic dissection (TBAD). To obtain an adequate proximal landing zone, coverage of the left subclavian artery (LSA) will often be necessary. The occurrence of possible neurologic complications has continued to be debated. We investigated the management of the LSA in patients with TBAD undergoing endovascular repair.

METHODS

We searched the PubMed and MEDLINE databases to October 2020 for studies of TEVAR for TBAD. Data on the study design, demographics, endograft details, LSA coverage and revascularization, mortality, complications, and follow-up were extracted and analyzed. The effects of LSA coverage and revascularization on neurologic complications and outcomes were investigated.

RESULTS

A total of 26 reports (24 retrospective and 2 prospective) were deemed eligible for our study. A total of 1483 patients (mean age, 56.9 ± 6.2 years) had undergone TEVAR for acute (n = 932; 62.9%), subacute (n = 36; 2.4%), or chronic (n = 515; 34.7%) TBAD, with a success rate of 97.8% and hospital mortality of 4.9%. The LSA origin had been covered for 707 patients (47.7%), and 326 had undergone LSA revascularization (surgical, n = 96; endovascular, n = 170; unspecified or not reported, n = 60). LSA revascularization was concomitant for 68.1% of cases, after TEVAR for 1.8%, and not reported for 30.1%. Of 1146 patients, 10 (0.9%) had experienced left arm claudication, and the overall stroke rate was 3.3% (2.7% for the LSA group and 1% for the uncovered LSA group; P = .0815). Of the patients with stroke and a covered LSA, 1% (2 of 203) had undergone LSA revascularization and 4.8% (5 of 105) had not (P = .0478). Twenty-six patients (1.9%) had developed paraplegia: 0.7% (3 of 433) with a covered LSA, 1.4% (7 of 491) with an uncovered LSA (P = .3508), and not reported for 16 patients. Endoleak was present in 138 patients (13.4%) at a mean follow-up of 32.1 ± 25.6 months.

CONCLUSIONS

Our review has shown that LSA coverage during endovascular repair for complicated TBAD will does not significantly increase the risk of neurologic complications; however, revascularization of the LSA should be always recommended.

Aortic remodeling after endovascular aortic repair and tailored distal entry tears exclusion in Crawford type III or IV dissection aneurysm

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) can only promote 55-80% false lumen (FL) thrombosis when only the proximal primary tear is covered during the repair of type B aortic dissection (TBAD). This study evaluated the effectiveness and clinical outcome of tailored exclusion of the primary entry tear with TEVAR and distal fenestrations with ancillary devices in patients with subacute or chronic Crawford type III and IV aortic dissection aneurysm.

METHODS

All patients underwent either TEVAR for primary entry tear; subsequently, various ancillary devices were applied on each distal fenestration. These techniques included covered stent occlusion of detached visceral artery entry tears, TL stenting and FL occlusion with vascular plugs in the common iliac artery dissection, or TEVAR coverage for multiple fenestrations from segmental arteries. This case series included nine patients (seven men and two women; mean age: 63.4 years) during January 2013 to May 2019. Outcome analysis included the rates of technical success and procedure-related complications, completeness of FL occlusion, aortic remodeling, and midterm mortality at 2 years.

RESULTS

The mean follow-up duration was 37.7 months without in-hospital mortality. One patient was lost to follow-up at the second month, the rest of patients were all alive during the follow-up period. All patients achieved complete FL thrombosis, and six patients exhibited aneurysm diameter shrinkage.

CONCLUSION

Tailored exclusion of visceral and iliac distal fenestrations with proximal primary tear coverage can promote FL thrombosis and aortic remodeling in the visceral aortic segment in patients with Crawford type III or IV aortic dissection aneurysm.

Thoracic endovascular aortic repair or best medical therapy for uncomplicated type B aortic dissection? A meta-analysis

INTRODUCTION

The aim of this meta-analysis was to investigate all studies comparing thoracic endovascular aortic repair (TEVAR) and best medical therapy (BMT) for the treatment of uncomplicated type B aortic dissection (TBAD).

EVIDENCE ACQUISITION

PubMed/Medline and Web of Knowledge were searched until September 2014 for relevant studies published in English. Pooled odds ratio (OR) and its corresponding 95% CI were analyzed with Cochrane Review Manager (RevMan v.5.3).

EVIDENCE SYNTHESIS

Our analysis showed that compared with BMT, TEVAR did not significantly affect 30-day (hospital) mortality. A significantly lower 1-year and 2- or 3-year survival rates was observed with TEVAR vs. BMT. Interestingly, a trend just short of statistical significance towards higher 4- or 5-year survival was found with TEVAR treatment (P=0.08). No significant differences were found in false lumen (FL) thrombosis formation with TEVAR vs. BMT treatment. However, a trend toward less incomplete or no FL thrombosis was noted with TEVAR. No significantly impact on the risk of later re-intervention was found with TEVAR vs. BMT.

CONCLUSIONS

TEVAR did not provide obvious early survival advantage for uncomplicated TBAD over BMT, especially in the patients using TEVAR alone. It may remain a treatment option in uncomplicated TBAD patients with high risks for later complications. More randomized, prospective, long-term studies are needed to further clarify whether TEVAR could be a better first-line treatment strategy vs. BMT for uncomplicated TBAD.

Endovascular repair of acute complicated type B aortic dissection-systematic review and meta-analysis of long-term survival and reintervention

Background

Thoracic endovascular repair (TEVAR) is considered the first-line therapy in the repair of acute complicated type B aortic dissection (AC-BAD). Given the difficulty of designing randomized trials in this surgical cohort, long-term outcome data is limited. This systematic review and meta-analysis provide a complete aggregation of reported long-term survival and freedom from reintervention of AC-BAD patients based on the existing literature.

Methods

Three databases were searched from date of database inception to January 2021. The relevant references were identified and baseline cohort characteristics, survival and freedom from reintervention were extracted. The primary endpoints were survival and freedom from reintervention, whilst secondary endpoints were post-operative outcomes such as cord ischemia and endoleak. Kaplan-Meier curves were digitized and aggregated as per established procedure.

Results

A total of 2,812 references were identified in the literature search for review, with 46 selected for inclusion. A total of 2,565 patients were identified, of which 1,920 (75%) were male. The mean age of the cohort was 59.8±5.8. Actuarial survival at 2, 4, 6 and 10 years was 87.5%, 83.2%, 78.5% and 69.7%, respectively. Freedom from all secondary reintervention at 2, 4, 6, 8 and 10 years was 74.7%, 69.1%, 65.7%, 63.9% and 60.9%, respectively. When accounting for study quality, actuarial survival at 2, 4, 6 and 8 years was 85.4%, 79.1%, 69.8% and 63.1%, respectively. Freedom from all secondary reintervention at 2, 4, 6 and 8 years was 73.2%, 67.6%, 63.7% (maintained), respectively.

Conclusions

TEVAR is associated with promising long-term survival extended to 10 years, though rates of freedom from reintervention remain an ongoing point for improvement. Randomized controlled trials comparing endovascular with open repair in the setting of acute, complicated type B aortic dissection are needed.

TEVAR for complicated and uncomplicated type B aortic dissection-Systematic review and meta-analysis

BACKGROUND

Type B aortic dissection (TBAD), is defined as a dissection involving the aorta distal to left subclavian artery with the ascending aorta and the aortic arch not affected. TBAD is classified due to the time frame and presence of complications. Complicated TBAD (co-TBAD) patients have a greater mortality rate than uncomplicated TBAD (un-TBAD) and thoracic endovascular aortic repair (TEVAR) is considered the gold-standard intervention for these clinical challenges.

METHODS

We undertook a systematic review of the literature regarding TEVAR intervention in co-TBAD and un-TBAD. A comprehensive search was undertaken across four major databases and was evaluated and assessed until June 2020.

RESULTS

A total of 16,104 patients were included in the study (7772 patients co-TBAD and 8352 un-TBAD). A significantly higher proportion of comorbidities were seen in co-TBAD patients compared with un-TBAD. Acute dissection was more frequent in the co-TBAD group (73.55% vs. 66.91%), while chronic dissection was more common in un-TBAD patients (33.8% vs. 70.73%). Postprocedure stroke was higher in co-TBAD (5.85% vs. 3.92%; p < .01), while postprocedural renal failure was higher in un-TBAD patients (7.23 vs. 11.38%; p < .01). No difference was observed in in-hospital mortality however the 30 days mortality was higher in the co-TBAD group. One-year survival was higher in the uncomplicated group but this difference was not observed in the 5-year survival.

CONCLUSION

In our analysis we can appreciate that despite significantly higher comorbidities in the co-TBAD cohort, there was no difference in in-hospital mortality between the two groups and the 5-year survival did not have any difference.

Clinical Utility of the Candy-Plug Technique Using an Excluder Aortic Extender

Objective: To describe the clinical utility and technical aspects of the candy-plug technique using an Excluder aortic extender (Ex-cuff) for false lumen (FL) occlusion in chronic aortic dissection. Materials and Methods: This is a retrospective study analyzing seven consecutive patients (mean age, 63 years; range, 44-78 years; 6 men) with aneurysmal dilatation or rupture in chronic aortic dissection. All patients had undergone thoracic endovascular aortic repair with FL occlusion using this technique. We assessed technical (deployment accuracy) and clinical (no FL backflow on the latest contrast-enhanced computed tomography) success. Results: Technical success was obtained in six patients (86%). Technical failure was caused by the malposition of the candy-plug. The mean follow-up period was 593 days (range, 222-1225 days). Clinical success was obtained in four (57%), and incomplete Amplatzer Vascular Plug (AVP) embolization was seen in two. There was no enlarged FL after the procedure, and all patients are alive during the follow-up periods. Conclusion: The candy-plug technique using an Ex-cuff may be a feasible option; however, it takes time to achieve complete AVP embolization. Therefore, using additional embolic materials should be considered when we use it for the rupture case. (This is a translation of Jpn J Endovasc Interv 2018; 19: 29-35.).

Short term outcome of thoracic endovascular aortic repair in patients with thoracic aortic diseases

AIM AND BACKGROUND

Open surgical repair for thoracic aortic diseases is associated with a high perioperative mortality and morbidity. Most of type B aortic dissections are uncomplicated and are medically treated which carries a high mortality rate. Thoracic endovascular aortic repair is the first-line therapy for isolated aneurysms of the descending aorta and complicated type B aortic dissection. The aim of this study is to test the safety of early thoracic endovascular aortic repair in patients with uncomplicated type B aortic dissection and patients with thoracic aortic aneurysms.

METHODS

A total of 30 patients (24 men and 6 females; mean age 59 ± 8 years) with uncomplicated type B aortic dissection and descending thoracic aortic aneurysm who underwent endovascular aortic repair in National Heart Institute and Cairo University hospitals were followed up. Clinical follow-up data was done at one, three and twelve months thereafter. Clinical follow-up events included death, neurological deficits, symptoms of chronic mal-perfusion syndrome and secondary intervention. Multi-slice computed tomography was performed at three and six months after intervention.

RESULTS

Of the 30 patients, 24 patients had aortic dissection, and 6 patients had an aortic aneurysm. 7 patients underwent hybrid technique and the rest underwent the basic endovascular technique in whom success rate was 100%. Two patients developed type I endoleak, however both improved after short term follow up. The total mortality rate was 10% throughout the follow-up. Both death and endoleak occurred in subacute and chronic cases, while using TEVAR in acute AD and aneurysm showed no side effects. Early thoracic endovascular aortic repair showed better results and less complications.

CONCLUSION

Along with medical treatment, early thoracic endovascular aortic repair in uncomplicated type B aortic dissections and thoracic aortic aneurysms is associated with better outcome.

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.

Comparison of thoracic endovascular aortic repair, open surgery and best medical treatment for type B aortic dissection: A meta-analysis

BACKGROUND

Treatments of type B aortic dissection (TBAD) include thoracic endovascular aortic repair (TEVAR), best medical treatment (BMT) and open surgery (OS). This meta-analysis was to compare these three strategies to evaluate which provides best outcomes.

METHODS

We searched clinical trials that compared treatment strategies for TBAD. The outcomes measures were 30-day/in-hospital mortality, long-term survival rate, paraplegia or paraparesis, renal failure, rupture, stroke, late re-intervention, late rupture and aneurismal dilatation/expansion.

RESULTS

Sixteen control trials covering 10,307 patients were evaluated. Meta-analysis showed that TEVAR provides preferable long-term survival rate (HR=0.71; 95% CI: 0.52-0.95), lower rate of late re-intervention (OR=0.33; 95% CI: 0.13-0.85), late rupture (OR=0.21; 95% CI: 0.10-0.43) and late aneurismal dilatation/expansion (OR=0.15; 95% CI: 0.04-0.63) compared with BMT. However, TEVAR seemed to be associated with higher stroke rate than BMT (OR=1.65; 95% CI: 1.21-2.23). 30-day/in-hospital mortality appeared to be lower in TEVAR (OR=0.49; 95% CI: 0.29-0.81) when compared with OS. In addition, OS induced higher 30-day/in-hospital mortality compared with BMT (OR=3.95, 95% CI: 1.56-10.02).

CONCLUSIONS

Our study shows that TEVAR may be favorable in long-term outcomes and effectively provide morphologic advantages compared to BMT. However, there is a need for prophylactic measures against stroke in TEVAR. OS seems to be inferior to TEVAR both in short-term and long-term outcomes. Further studies especially randomized clinical trials are needed to comprehensively compare the efficacy between TEVAR and BMT.

Endovascular Repair in Acute Complicated Type B Aortic Dissection: 3-Year Results from the Valiant US Investigational Device Exemption Study

Acute complicated type B aortic dissection (TBAD) is a potentially catastrophic, life-threatening condition. If left untreated, there is a high risk of aortic rupture, irreversible organ or limb damage, or death. Several risk factors have been associated with acute complicated TBAD, including age and refractory hypertension. In the acute phase, even uncomplicated patients are more prone to develop complications if hypertension and pain are left medically untreated. Innovations in stent graft technologies have incrementally improved outcomes since their first use for this condition in 1999, though improvement is needed in mitigating periprocedural complications, adverse events, and mortality. In the past decade, endovascular repair has become the preferred treatment because of its superior outcomes to open repair and medical therapy. The Valiant Captivia Thoracic Stent Graft System is a third-generation endovascular stent graft with advancements in minimally invasive delivery, conformability to the anatomy, and the minimization of adverse sequelae. Herein, this stent graft is briefly reviewed and its 3-year outcomes are presented. Freedom from all-cause and dissection-related mortality was 79.1% and 90.0%, respectively. The Valiant Captivia Stent Graft represents a safe, effective intervention for acute complicated TBAD. Continued surveillance is needed to verify its longer-term durability.

Successful Repair of Acute Type B and Retrograde Type A Aortic Dissection With Kidney Ischemia

Acute dissection of thoracic aorta carries a risk of renal ischemia followed by the development of a kidney failure. The optimal surgical and nonsurgical management of these patients, timing of intervention, and the factors predicting renal recovery are not well delineated and remain controversial. We present a case of acute type B thoracic aortic dissection with left kidney ischemia. Evaluation of renal function was performed by the means of internationally accepted Risk, Injury, Failure, Loss of kidney function, End stage kidney disease and Acute Kidney Injury Network classifications for acute kidney injury, renal duplex sonography, and intravascular ultrasound that demonstrated left renal artery dissection with a flap completely compressing the true lumen. The patient underwent thoracic endovascular aortic repair and left renal artery stent and recovered well. Six months later, at the follow-up visit, retrograde type A aortic dissection was found, which was successfully repaired. Reversal of renal ischemia after aortic dissection depends on the precise assessment of renal function and prompt intervention.

Standardized Protocol to Analyze Computed Tomography Imaging of Type B Aortic Dissections

Purpose: To propose a standard measuring protocol for type B aortic dissections so as to improve comparability between studies reporting aortic dimensions. Methods: Fifteen computed tomography (CT) scans of type B aortic dissections were measured with a standard protocol by 2 independent observers using postprocessing software. The following parameters were assessed: true, false, and total lumen diameter; true and false lumen volume; and entry tear size, location, and number. Diameters were measured in a perpendicular plane at 2, 10, and 20 cm from the left subclavian artery and 5 cm from the most distal renal artery. True lumen volume was assessed from the left subclavian artery to the aortic bifurcation, while the false lumen volume was from the start to end up to the aortic bifurcation. Entry tear location was assessed in relation to the left subclavian artery. Intra- and interobserver repeatability and agreement were evaluated using the Bland-Altman method, an a priori set of acceptable differences, and Lin’s concordance correlation coefficient (LCCC). Results: Intra- and interobserver mean differences for aortic diameter and true and false lumen volumes were generally within the limits of agreement and the a priori differences; the LCCC showed excellent agreement. Entry tear location, size, and number were difficult to measure in a repeatable manner, with inconsistent correlation coefficients, especially between the 2 observers. Conclusion: This protocol showed acceptable repeatability for aortic diameter and aortic volume measurements. Assessment of entry tears proved challenging and associated with less favorable results. Additionally, investigators are urged to be more transparent regarding the measurement methodology used in studies describing aortic dimensions.

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.

Biomechanical Changes After Thoracic Endovascular Aortic Repair in Type B Dissection

Thoracic endovascular aortic repair (TEVAR) has evolved into an established treatment option for type B aortic dissection (TBAD) since it was first introduced 2 decades ago. Morbidity and mortality have decreased due to the minimally invasive character of TEVAR, with adequate stabilization of the dissection, restoration of true lumen perfusion, and subsequent positive aortic remodeling. However, several studies have reported severe setbacks of this technique. Indeed, little is known about the biomechanical behavior of implanted thoracic stent-grafts and the impact on the vascular system. This study sought to systematically review the performance and behavior of implanted thoracic stent-grafts and related biomechanical aortic changes in TBAD patients in order to update current knowledge and future perspectives.

Type B Aortic Dissection: A Review of Prognostic Factors and Meta-analysis of Treatment Options

According to international guidelines, stable patients with uncomplicated Type B aortic dissection (TBAD) should receive optimal medical treatment. Despite adequate antihypertensive therapy, the long-term prognosis of these patients is characterized by a significant aortic aneurysm formation in 25-30% within four years, and survival rates from 50 to 80% at five years and 30 to 60% at 10 years. In a prospective randomized trial, preemptive thoracic endovascular aortic repair (TEVAR) in patients with chronic uncomplicated TBAD was associated with an excess early mortality (due to periprocedural hazards), but the procedure showed its benefit in prevention of aortic-specific mortality at five years of follow-up. However, preemptive TEVAR may not be the treatment of choice in all patients with uncomplicated TBAD because of the inherent periprocedural complications like stroke, paraparesis, and death, as well as stent graft-induced complications (i.e., retrograde dissection or endoleaks). Thus, the TEVAR-related deaths and complications (especially paraplegia and stroke) raise concerns that moderate the better survival with TEVAR at five years. By timely identification of those patients prone for developing complications, early intervention, preferably in the subacute or early chronic phase, may improve the overall long-term outcome for these patients. Therefore, early detectable and reliable prognostic factors for adverse events are essential to stratify patients who can be treated medically and those who will benefit from rigorous follow-up and, in the long-term, from timely, or even prophylactic, TEVAR. Several studies have identified prognostic factors in TBAD such as aortic diameter, partial false lumen thrombosis, false lumen thickness, and location of the primary entry tear. Combining these clinical and radiological predictors may be essential to implement a patient-specific approach designed to intervene only in those patients who are at high risk of developing complications to improve the long-term outcomes of patients with uncomplicated Type B aortic dissection.

Dynamic MR angiography in acute aortic dissection

BACKGROUND

To evaluate the benefit (additional flow information), image quality, and diagnostic accuracy of a dynamic magnetic resonance angiography (MRA) combining high spatial and temporal resolution for the preinterventional assessment of acute aortic dissection.

METHODS

Nineteen patients (12 men, 7 women; aged 32-78 years) with acute aortic dissection underwent contrast-enhanced four-dimensional (4D) MRA and 3D conventional high-resolution MRA (3D MRA) within one examination on a 1.5 Tesla MR system. Both MRA datasets for each patient were evaluated and compared for image quality and visualization of vascular details on a 5-point scale (5 = excellent image quality, 1 = nondiagnostic image quality). In addition, presence and relevance of additional hemodynamic information (flow direction and organ perfusion delay) gained by dynamic MRA were assessed.

RESULTS

Conventional 3D MRA provided significantly higher values for image quality of the aorta and aortic side branches compared with dynamic MRA (aorta: 4.3 versus 3.3; P = 0.006 side branches: 4.2 versus 3.3; P = 0.02). However, in 10 of the 19 patients (53%) the additionally available information on flow dynamics due to dynamic MRA (e.g., delayed perfusion of parenchymal organs) led to a change in therapy planning and realization.

CONCLUSION

Dynamic MRA is a technique that combines functional flow and morphological information. Thus, the combination of 3D and dynamic MRA provides all requested information for treatment planning in patients suffering from acute aortic dissection.

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.

Treatment of acute type-B aortic dissection: thoracic endovascular aortic repair or medical management alone?

OBJECTIVES

This study sought to evaluate the early and long-term effect of thoracic endovascular aortic repair (TEVAR) on type-B acute aortic dissection (AAD).

BACKGROUND

Uncomplicated type-B AAD is generally treated with medical management; complicated dissections require surgery or TEVAR. Studies have demonstrated that long-term outcomes with medical management are suboptimal. Therefore, we sought to determine the long-term effect of TEVAR compared with medical management alone on type-B AAD.

METHODS

From January 2004 to May 2008, 193 consecutive patients in 2 hospitals were treated and retrospectively placed into 1 of 2 groups: 1) the TEVAR group-type-B AAD treated with TEVAR and antihypertensive medications (n = 152); and the 2) medicine group-uncomplicated type-B AAD treated medically alone (n = 41). All TEVAR procedures were performed in the acute phase.

RESULTS

There were no significant differences in demographics, comorbidity profiles, or early events between groups. The cumulative freedom from all late adverse events at 1, 3, and 5 years was 97%, 89%, and 67% in the TEVAR group and 97%, 63%, and 34% in the medicine group. Log-rank tests showed that medically treated patients had more late adverse events than TEVAR-treated patients did (p = 0.003). The 5-year cumulative survival rate from all-cause death was not significantly different between the 2 groups.

CONCLUSIONS

Patients with type-B AAD treated with TEVAR experienced fewer late adverse events than those treated with medical management, but there was no significant difference among the groups in 5-year mortality rates. Further studies of longer-term survival rates are needed to determine whether TEVAR could be an effective treatment for type-B AAD.

Endovascular Versus Medical Therapy for Uncomplicated Type B Aortic Dissection

Background:

Uncomplicated type B dissections have been traditionally managed with antihypertensive therapy. In the endovascular era, this dictum has been revisited. This review pooled the available studies to compare the outcomes of best medical therapy (BMT) to thoracic endovascular aortic repair (TEVAR) for uncomplicated type B dissections.

Methods:

A literature search was performed to identify studies on uncomplicated type B dissections managed with BMT with and without TEVAR. The primary outcome measures were mortality rates at 30 days and at 2 years following intervention.

Results:

A total of 6 studies included 123 patients who underwent TEVAR/BMT, and 566 patients who had BMT alone. The mortality rates at 30 days (6.5% TEVAR/BMT vs 4.8% BMT, P = .21) and at 2 years (9.7% vs 11.9%, P = .32) were similar. Renal failure was greater in TEVAR/BMT (15.4% vs 2.1%, P < .01). Rates of surgical reintervention/intervention were similar (17.6% vs 20.1%, P = .31).

Conclusion:

The TEVAR with BMT does not provide survival benefit compared to BMT alone, 2 years following uncomplicated type B aortic dissection.

Endovascular versus conventional medical treatment for uncomplicated chronic type B aortic dissection

BACKGROUND

Aortic dissection is a potentially life-threatening condition that occurs when a tear forms in the inner lining of the aorta. It has traditionally been treated by blood pressure control (medical treatment) or open surgery, both with high mortality rates. More recently stent-graft repair has been suggested as an alternative.

OBJECTIVES

To identify the best management for uncomplicated (without rupture of the organs or malperfusion of the extremities) subacute or chronic type B aortic dissection.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched their Specialised Register (last searched May 2012) and CENTRAL (2012, Issue 4). Clinical trials databases were searched for ongoing or unpublished studies.

SELECTION CRITERIA

All randomised controlled trials designed to compare the outcome of uncomplicated (without rupture of the organs or malperfusion of the extremities) chronic (occurring more than two weeks previously) type B aortic dissection when treated by stenting adjunctive to best medical treatment versus best medical treatment alone were included.

DATA COLLECTION AND ANALYSIS

Data on all cause and aorta-related mortality at two years was collected and analysed. In addition, secondary outcome measures were analysed, including morbidity, complications (additional endovascular or open surgery for rupture, expansion or malperfusion) and quality of life.

MAIN RESULTS

A single trial was identified that fulfilled the inclusion criteria (INSTEAD trial). The two-year all cause survival was not statistically significantly different between study groups (95.6% ± 2.5% in the optimised medical therapy (OMT) group and 88.9% ± 3.7% in the thoracic endovascular aneurysm repair (TEVAR) + OMT group; log rank test P = 0.15).

AUTHORS' CONCLUSIONS

Overall, the data at two years were insufficient to make any practice recommendations. However, the data on the anatomic remodeling of dissected aortas observed after TEVAR + OMT is encouraging and future studies should follow up cases for at least five years to see if early endovascular interventions, even in stable initially uncomplicated type B patients, are of long-term benefit.

Management of acute complicated and uncomplicated type B dissection of the aorta: focus on endovascular stent grafting

Endovascular repair of aortic dissection is the subject of multiple studies. This article aims to review the current literature on Type B complicated and uncomplicated dissection, including indications for medical therapy, open surgical therapy, and endovascular therapy. The review suggests a benefit for thoracic endovascular aortic repair in complicated dissection and medical therapy for uncomplicated dissection. Upcoming trials may shed more light on this issue.

Thoracic EndoVascular Stent Graft Repair for Aortic Aneurysm

BACKGROUND

The number of cases employing thoracic endovascular aortic repair (TEVAR) has been increasing due to lower morbidity and mortality compared to open repair technique. The aim of this study is to evaluate the outcome of TEVAR for thoracic aortic diseases.

MATERIALS AND METHODS

Sixteen patients underwent TEVAR from October 2003 to April 2010. Mean age at operation was 59 years (20~78 years), and 11 were male. Indications for TEVAR were large aortic diameter (>5.5 cm) upon presentation in 6 patients, increasing aortic diameter during the follow-up period in 4, traumatic aortic rupture in 3, persistent chest pain in 2, and ruptured aortic aneurysm in one. The mean diameter, length and the number of the stents were 33 mm (26~40 mm), 12 cm (9.5~16.0 cm), and 1.25 (1~2), respectively. Aortography employing Multi-detector computerized tomography (MDCT) technique was performed at one week, and patients were followed up in the out-patient department at one month, 6 months, and one year postoperatively.

RESULTS

Primary technical success showing complete exclusion of the aneurysm was achieved in 15 patients. One patient showed a small endo-leak (type 1). Four patients developed perioperative stroke: Three recovered without sequelae, and one showed mild right-side weakness. There was no operative mortality. Diameter of the thoracic aorta covered by stent graft changed within 10% range in 12 patients, decreased by more than 10% in 3, and increased by more than 10% in one during mean follow-up duration of 18 months (1~73 months). There was no recurrence-related death during this period.

CONCLUSION

Intermediate-term outcome after TEVAR was encouraging. Indications for TEVAR could be extended for other thoracic aortic diseases.

Acute complicated and uncomplicated type III aortic dissection: an endovascular perspective

Type III aortic dissection is associated with high morbidity and mortality. There is a shifting paradigm in the treatment of complicated and uncomplicated acute type III aortic dissection toward earlier endovascular repair. In this review, the authors present the current perspective on the endovascular management of acute complicated and uncomplicated type III aortic dissection.