Surgical treatment patterns and clinical outcomes of type B aortic dissection involving the aortic arch

Comparisons of open surgical repair, thoracic endovascular aortic repair, and optimal medical therapy for acute and subacute type B aortic dissection: a systematic review and meta-analysis

BACKGROUND

Various treatments have been employed in managing type B aortic dissection (TBAD), encompassing open surgical repair (OSR), thoracic endovascular aortic repair (TEVAR), and optimal medical therapy (OMT). Nonetheless, the determination of the most efficacious treatment protocol remains a subject of debate. We aim to compare the treatments in patients with acute and subacute TBAD using a meta-analytic approach.

METHODS

A systematic search was conducted across databases including PubMed, EmBase, and the Cochrane Library for relevant studies published from their inception up to September 2024. Studies comparing OSR, TEVAR, and OMT for TBAD through controlled or direct comparative designs were incorporated. Pairwise comparison meta-analyses were performed employing odds ratios (OR) alongside 95% confidence intervals (CIs) to quantify intervention effects by using the random-effects model.

RESULTS

Thirty-one studies involving 34,681 patients with TBAD were included in the final meta-analysis. We noted OSR were associated with an increased risk of in-hospital mortality (OR: 2.41; 95%CI: 1.67-3.49; P < 0.001), paraplegia (OR: 3.60; 95%CI: 2.20-5.89; P < 0.001), limb ischemia (OR: 7.80; 95%CI: 2.39-25.49; P = 0.001) and bleeding (OR: 9.54; 95%CI: 6.57-13.85; P < 0.001) as compared with OMT. Moreover, OSR versus TEVAR showed an increased risk of in-hospital mortality (OR: 2.67; 95%CI: 1.92-3.72; P < 0.001), acute renal failure (OR: 1.98; 95%CI: 1.61-2.42; P < 0.001), myocardial infaraction (OR: 2.76; 95%CI: 1.64-4.65; P < 0.001), respiratory failure (OR: 2.19; 95%CI: 1.73-2.76; P < 0.001), or bleeding (OR: 1.88; 95%CI: 1.33-2.67; P < 0.001), and lower risk of reintervention (OR: 0.30; 95%CI: 0.10-0.89; P = 0.030). Finally, TEVAR was associated with an increased risk of stroke (OR: 1.77; 95%CI: 1.41-2.21; P < 0.001), limb ischemia (OR: 13.00; 95%CI: 4.33-39.06; P < 0.001), and bleeding (OR: 3.65; 95%CI: 2.40-5.55; P < 0.001) as compared with OMT.

CONCLUSIONS

This study systematically compared various treatments and showed their safety and efficacy for acute and subacute TBAD. The results require further large-scale randomized controlled trials.

Aortic Outcome after Implementation of a Treatment Strategy for Type B Aortic Dissection Involving the Aortic Arch

OBJECTIVE

To evaluate the outcomes achieved after implementing a treatment strategy for non-A non-B (NANB) (B 1-2 D according to the latest consensus document of the Society of Vascular Surgery (SVS) and Society of Thoracic Surgeons (STS) acute aortic dissection (AAD)).

METHODS

This retrospective observational study adhered to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist. All cases of NANB AAD (B 1-2 D) treated at our institution between January 2016 and December 2022 were reviewed. Morbidity, mortality, aortic-related reintervention, and remodeling were analyzed.

RESULTS

Among 519 cases of acute aortic syndrome, n = 22 (4.2%) patients presented with NANB AAD (B 1-2 D) (n = 16,72.7% men, mean age 61.5 years+/14.7). Eleven cases were managed with best medical treatment (BMT) alone. Among them, one patient (9.1%) died suddenly 2 days after diagnosis for aortic rupture. Frozen elephant trunk procedure (FET) was required in the remaining 11 patients: 7 (31.8%) needed emergent operation for risks of impending aortic rupture or retrograde aortic dissection extension, and 4 (26.7%) underwent delayed surgery within a month from initial presentation. Overall, in-hospital mortality was 9.1% with both FET and BMT. At a median follow-up of 40 months (range 2 days-200 months) no other deaths occurred. A statistically significant differences in the rate of false lumen thrombosis (100% vs 55.5%, P = 0.033), and a significant positive aortic remodeling in zone 3 (P < 0.001) and 4 (P = 0.038) were reported in operated versus medically managed patients.

CONCLUSIONS

The best treatment for NANB is not established. We advocate for medical stabilization with an operative approach that favors open surgery in the acute post dissection period, promotes aortic remodeling, and carries acceptable risk in centers where FET is performed routinely.

The Interdisciplinary Aortic Team: Opportunities for Collaboration in Acute Aortic Syndromes

Interdisciplinary teams offer potential advantages over siloed care models in complex cardiovascular disease management. Consensus guidelines for aortic management have increasingly identified the interdisciplinary aortic team as a key component in delivering quality care. Acute aortic syndromes are a subset of high acuity and lethal aortic pathologies that may benefit from an interdisciplinary approach. The advantages of the interdisciplinary aortic team model in the management of acute aortic syndromes and barriers to implementation are discussed.

Patient-Tailored Therapy for Complex Aortic Arch Anatomy: An Evolving Research Field with Custom-Made Solutions

The treatment of complex aortic pathologies requires specialized techniques and tailored approaches due to each patient's unique anatomical and clinical challenges. The European Association for Cardiothoracic Surgery (EACTS) and the Society of Thoracic Surgeons (STS) new guidelines identify the aorta as the body's 24th organ and reiterate that multidisciplinary aortic teams are recommended for shared decision-making to determine optimal treatment strategies. Patients treated for conditions such as aneurysms, dissections, intramural hematomas, or penetrating aortic ulcers may develop complex forms over time, necessitating careful follow-up and timely corrective actions. Endovascular solutions can be favorable for older patients with complex anatomies and multiple comorbidities. However, when endovascular treatment is not feasible, hybrid treatments or open surgery must be considered if the patient's condition allows it. The risk-benefit ratio of each procedure must be carefully evaluated; choosing the best intervention or deciding not to intervene becomes a critical and challenging decision. At our Cardiac Surgery Center in Verona, a multidisciplinary team with over 20 years of experience in treating complex aortic arch pathologies extensively discussed different cases of complex aortic pathologies treated with endovascular, hybrid, or surgical approaches, emphasizing the importance of considering both anatomical and patient-specific characteristics. The decisions and treatments were often challenging, and unanimity was not always achieved, reflecting the complexity of finding the best solutions.

A Scoping Review of Definitions of Success in Endovascular Aortic Arch Repair

INTRODUCTION

The present standard of care to treat aortic arch pathologies is open surgical repair with cardiopulmonary bypass and deep hypothermic arrest. With approaches for total endovascular and extra-anatomic cervical debranching hybrid arch repair becoming more diverse, understanding what is considered a successful operation is prerequisite for a rigorous comparison of techniques. This review describes the specific outcomes reported, the rates of success, and the definitions of technical and clinical success in total endovascular and extra-anatomic cervical debranching hybrid aortic arch repair.

METHODS

A comprehensive search of MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials was performed. Studies with patients undergoing total endovascular or hybrid extra-anatomic cervical debranching repair of the aortic arch were included. Any publications including only patients with Ishimaru zone 2 or distal repairs were excluded from this review. Studies with less than 5 patients were excluded. Data extraction was performed by one author. Data items included were study design, procedure type, procedural details, underlying pathology, type of cervical debranching, type of endograft repair, surgical outcomes, definition of cerebrovascular events, technical success, and the definition of technical success.

RESULTS

Of 1754 studies screened for review, 85 studies with 5521 patients were included. By frequency, the included studies examined the following interventions: fenestrated devices, branched devices, parallel grafting. Most studies were retrospective single-institution studies. There were no randomized controlled trials. Short-term mortality and cerebrovascular events were nearly universally reported, present in 99% and 95% of studies reviewed, respectively. Only 27% of studies provided an explicit definition for cerebrovascular events. While 75% of studies reported a technical success rate, only 45% of those studies provided explicit criteria. Clinical success rates were infrequently reported, present in only 5.9% of studies reviewed.

CONCLUSION

The definitions of technical success that were provided fell short of analogous defined reporting standards in nearly all studies, inflating technical success rates. Definitions of cerebrovascular events and technical success require stringent criteria to uniformly compare various methods of endovascular aortic arch repair. A societal consensus document for reporting standards of endovascular aortic arch repair would allow for higher-quality outcomes research.

CLINICAL IMPACT

Total endovascular and extra-anatomic cervical debranching hybrid operations are being increasingly utilized for complex aortic arch repair. These techniques, however, can be associated with serious complications. Currently, there is no accepted metric to define technical or report clinical outcomes. Due to the paucity of high-quality data, use of these approaches may be limited in clinical practice. This study emphasizes the need for the development of standards for reporting outcomes in endovascular aortic arch repair. Future studies can then utilize these benchmarks, whcih will allow for improved efficacy and safety in these techniques.

Six-Year Outcomes of Total Arch Replacement vs Debranching With TEVAR for Aortic Arch Pathologies: Meta-Analysis of Kaplan-Meier-Derived Data From Propensity Score-Matched Studies

BACKGROUND

Total arch replacement (TAR) and debranching plus thoracic endovascular aortic repair (TEVAR) serve as significant therapeutic options for aortic arch pathologies. It remains unclear whether one of these approaches should be considered preferable. Our study aimed to compare the long-term outcomes of these 2 approaches.

METHODS

We carried out a pooled meta-analysis of time-to-event data extracted from studies published by December 2023. Eligibility criteria included populations with any aortic arch pathology who underwent debranching plus TEVAR or TAR, propensity score-matched (PSM) studies (prospective/retrospective; single-center/multicentric), and the outcomes included follow-up for overall survival/mortality and/or reinterventions.

RESULTS

Eleven PSM studies met our eligibility criteria, including a total of 1142 patients (571 matched pairs). We did not observe any statistically significant difference in the risk of all-cause death between the groups (hazard ratio [HR]=1.20, 95% confidence interval [CI]=0.91-1.56, p=0.202), but patients who underwent TAR had a significantly lower risk of late aortic reinterventions compared with patients who underwent debranching plus TEVAR (HR=0.38, 95% CI=0.23-0.64, p<0.001). Our meta-regression analyses for all-cause mortality identified statistically significant coefficients for age (coefficient=-0.047; p=0.012) and type A aortic dissections (coefficient=0.012; p=0.010).

CONCLUSIONS

Debranching plus TEVAR and TAR demonstrate no statistically significant differences in terms of survival in patients with aortic arch pathologies, but TAR is associated with lower risk of late aortic reinterventions over time. Although older patients may benefit more from debranching plus TEVAR rather than from TAR, patients with dissections may benefit more from TAR.

CLINICAL IMPACT

Although the 2 strategies seem to be equally valuable in terms of survival, total aortic arch replacement (when compared with debranching plus TEVAR to treat patients with aortic arch pathologies) is associated with reduction of late aortic reinterventions over time in patients with and without aortic dissections. However, we should consider debranching plus TEVAR in older patients as it is associated with lower risk of death in this population. The novelty of our study lies in the fact that, instead of comparing study-level effect estimates, we analyzed the outcomes with reconstructed time-to-event data. This offered us the opportunity of performing our analyses with a mathematically appropriate model which consider events and time; however, these findings might be under the influence of treatment allocation bias.

Differences in In-Hospital and Follow-Up Outcomes Between Non-A Non-B Aortic Dissection and Type B Aortic Dissection Treated by Endovascular Based Treatment

OBJECTIVES

Non-A non-B aortic dissection (AD) is a rare and life-threatening medical emergency, and it has been controversial whether it should be managed as type B aortic dissection (TBAD). The study aims to compare in-hospital and follow-up outcomes between patients with non-A non-B AD and those with TBAD treated by endovascular based treatment (EBT).

METHODS

From January 2017 to December 2021, 96 consecutive patients with non-A non-B AD met the inclusion criteria and underwent EBT. Patients with TBAD were matched to patients with non-A non-B AD at a 1:1 ratio using propensity score matching analysis to correct for baseline confounding factors. The primary endpoint was all-cause mortality. Aortic-related events were defined as dissection-related death, aortic rupture, retrograde type A aortic dissection, reintervention, and type Ia endoleak.

RESULTS

Patients with non-A non-B AD required more TEVAR-related adjunctive procedures compared to TBAD patients during EBT and they required a longer ICU length of stay (36.0 vs 24.0 hours, P < .05) as well as a longer hospitalization (8.0 vs 7.0 days, P < .05) after EBT. There was no statistical difference in overall survival after EBT for patients with TBAD and non-A non-B AD. However, compared to patients with TBAD, non-A non-B AD patients had a higher rate of reintervention and experienced more aortic-related late events during follow-up.

CONCLUSION

Patients with non-A non-B acute AD who are treated with EBT do not have higher in-hospital or follow-up mortality rates compared to patients with type B AD. However, there is an increased risk of reintervention and aortic-related late events after the intervention during follow-up.

Current knowledge and contemporary management of non-A non-B aortic dissections

Non-A non-B aortic dissection (AAD) is an infrequently documented condition, comprising of only a small proportion of all AADs. The unique anatomy of the aortic arch and the failure of the existing classifications to adequately define individuals with non-A non-B AAD, have led to an ongoing controversy around the topic. It seems that the clinical progression of acute non-A non-B AAD diverges from the typical type A and B dissections, frequently leading to serious complications and thus mandating early intervention. Currently, the available treatment methods in the surgical armamentarium are conventional open, endovascular techniques and combined hybrid methods. The optimum approach is tailored in every individual case and may be determined by the dissection’s location, extent, the aortic diameter, the associated complications and the patient’s status. The management of non-A non-B dissections still remains challenging and a unanimous consensus defining the gold standard treatment has yet to be reached. In an attempt to provide further insight into this perplexing entity, we performed a minireview of the literature, aiming to elucidate the epidemiology, clinical course and the optimal treatment modality.