The Aortic Team Model for the Management of the Distal Arch, Descending Thoracic and Thoracoabdominal Aorta: Appraisal at 3 Years.

BACKGROUND: This study aimed to assess feasibility, logistical challenges, and clinical outcomes associated with the implementation of an Aortic Team model for the management of distal arch, descending thoracic and thoracoabdominal aortic disease. METHODS: An Aortic Team care pathway was implemented in November 2019. Working as a unit, two cardiac surgeons, two vascular surgeons, an interventional radiologist, a cardiologist, and an anesthesiologist collectively determined care decisions via multispecialty presence at an Aortic Clinic. Cardiac and vascular surgeons operated in tandem for open procedures. Interventional radiology participated alongside cardiac and vascular for endovascular procedures. Cardiology aided in medical therapies for heritable and degenerative disease, and had a lead role for genetics and high-risk pregnancy referrals. The model spanned three hospitals. Clinical outcomes at 3 years were assessed. RESULTS: There were 35 descending thoracic and thoracoabdominal surgeries and 77 thoracic endovascular aortic repairs. Endoarch devices were used in 7 cases (Gore Thoracic Branch Endoprosthesis, 4, Terumo RelayBranch, 3) and an endothoracoabdominal device in 4 cases (Cook Zenith t-branch). The Aortic Clinic acquired 456 patients, with yearly increases (54 patients [year 1], 181 patients [year 2], 221 patients [year 3]). For surgery, mortality was 8.6% (3/35), permanent paralysis 5.7% (2/35), stroke 8.6% (3/35), permanent dialysis 0%, and reinterventions 8.6% (3/35). For endovascular cases, mortality was 3.9% (3/77), permanent paralysis 3.9% (3/77), stroke 5.2% (4/77), permanent dialysis 1.3% (1/77), and reinterventions 16.9% (13/77). CONCLUSION: An Aortic Team model is feasible and ensures all treatment options are considered. Conventional open thoracoabdominal procedures showed acceptable outcomes. Endoarch technology shows early promise.

The Aortic Team Model and Collaborative Decision Pathways for the Management of Complex Aortic Disease: Clinical Practice Update From the Canadian Cardiovascular Society/Canadian Society of Cardiac Surgeons/Canadian Society for Vascular Surgery/Canadian Association for Interventional Radiology.

Disease of the aortic arch, descending thoracic, or thoracoabdominal aorta necessitates dedicated expertise across medical, endovascular, and surgical specialties. Cardiologists, cardiac surgeons, vascular surgeons, interventional radiologists, and others have expertise and skills that aid in the management of patients with complex aortic disease. No specialty is uniformly expert in all aspects of required care. Because of this dispersion of expertise across specialties, an aortic team model approach to decision-making and treatment is advocated. A nonhierarchical partnership across specialties within an interdisciplinary aortic clinic ensures that all treatment options are considered and promotes shared decision-making between the patient and all aortic experts. Furthermore, regionalization of care for aortic disease of increased complexity assures that the breadth of treatment options is available and that favourable volume-outcome ratios for high-risk procedures are maintained. An awareness of best practice care pathways for patient referrals for preventative management, acute care scenarios, chronic care scenarios, and pregnancy might facilitate a more organized management schema for aortic disease across Canada and improve lifelong surveillance initiatives.

Aortic arch endovascular branch and fenestrated repair: Initial Canadian experience with novel technology.

Objective: The objective is to describe the initial Canadian experience using novel aortic arch branched endograft technologies. Methods: We performed a retrospective consecutive case series of all patients undergoing aortic arch branched repair with newly available endograft technology since 2020 at our site. We describe the patient characteristics, treatment characteristics, and postoperative outcomes. Results: Eleven patients received arch branched endografts, indicated for penetrating aortic ulcer in seven patients (64%), arch degeneration after prior aortic dissection repair in three (27%), and acute aortobronchial fistula in one patient (9%). Their average age was 72 ± 7 years. Complete arch repair from zone 0 to 4 was performed in six cases (55%); the remaining repairs landed proximally in zones 1 or 2. Seven repairs used a single retrograde facing inner branch (thoracic branch endoprosthesis; W.L. Gore & Associates), three used double antegrade inner branch (Bolton Relay; Terumo Interventional Systems), and one emergent case used double in situ fenestrations. Seven repairs (64%) used an adjunctive extra-anatomic bypass to complete great vessel perfusion, two of which were created during a prior aortic repair. Inferior vena cava balloon inflow occlusion during deployment was used in all cases. No mortalities, transient or permanent spinal cord paralysis, myocardial infarction, dialysis dependence, venous thromboembolism, or bleeding requiring reintervention occurred. No patient undergoing elective arch branch repair experienced a stroke. The one patient undergoing emergent repair did suffer a stroke. The median length of stay was 5 days (interquartile range, 2-8 days). Two endoleaks developed: a type Ia endoleak successfully treated with a Palmaz stent (Cordis) during the index admission, and a type II endoleak with ongoing sac regression on postoperative follow-up. Postoperatively, one patient suffered a suspected aortic graft infection that was treated with lifelong antibiotics. During a mean radiographic follow-up of 7.2 months, no cases of branch vessel instability (ie, no migration, reintervention, arterial rupture, intraluminal thrombus, occlusion, stenosis, or kinking of the branch grafts) developed. Three patients experienced sac regression of >5 mm, and no patient experienced continued postoperative dilation. Conclusions: To the best of our knowledge, this is the largest reported Canadian volume of aortic arch repair using novel branched or fenestrated technology. The series demonstrates that a multidisciplinary program and properly selected patients can yield excellent results using endovascular repair for complex aortic arch pathology.

A Systematic Review of Total Endovascular Aortic Arch Repair: A Promising Technology.

BACKGROUND: Total endovascular aortic arch repair (TEAAR) represents an emerging alternative for the treatment of aortic arch disease in patients at prohibitive risk for open surgery. A systematic review of TEAAR was performed to delineate early outcomes with this new technology. METHODS: All studies (excluding single-patient case reports) of CE-certified "custom made" or "off-the-shelf" zone 0 stent graft deployments were included. The primary search of Medline, Embase, CINAHL, and the Cochrane CENTRAL registry was supplemented with searches of Web of Science, ClinicalTrials.gov, and conference abstracts (within last 3 years), and a hand search of citations within relevant articles. Articles underwent 2-stage screening by 2 independent reviewers before inclusion. RESULTS: Fifteen relevant investigations were identified. Indications for TEAAR were chronic arch dissection with degenerative aneurysmal disease (54%, 148/273), pure arch aneurysm (41%, 112/273), penetrating atherosclerotic ulcer (2%, 5/273), and type IA endoleak from a zone 2 thoracic endograft (1%, 3/273). Double-branch (70%, 192/273), triple-branch (19%, 53/273), and single-branch (into innominate artery; 10%, 28/273) devices were used. Adjunct left carotid-subclavian bypass occurred in 90% of double- and single-branch procedures. Procedural success with TEAAR was 93% (95% CI 85.8%-96.3%). The proportion of all-cause mortality was 16% (95% CI 8%-26%), stroke 14% (8%-24%), peripheral vascular events 7% (1%-33%), and myocardial infarction 4% (2%-7%). Endoleaks were identified in 13% (7%-25%) of the study population. CONCLUSIONS: TEAAR represents an emerging option for the management of aortic arch disease wth high procedural success rates and acceptable early outcomes in a high-risk patient population.

Zone 0 Aortic Arch Reconstruction Using the RelayBranch Thoracic Stent Graft.

Endovascular therapies have had a considerable impact on contemporary management of thoracic aortic disease. Still, with the anatomic challenges of the aortic arch, endovascular experience with devices that traverse the arch and deploy in the Zone 0 position remains limited. We report the first Canadian experience with the RelayBranch Thoracic Stent Graft (Terumo Aortic, Sunrise, FL) with Zone 0 deployment for total endovascular aortic arch repair in a patient at very high risk for redo open surgery. We demonstrate safe deployment of the device and successful treatment of a type 1A endoleak. Features of the RelayBranch design that mitigate challenges of arch deployment are also discussed.

Les traitements endovasculaires ont eu un impact considérable sur la gestion contemporaine des pathologies de l'aorte thoracique. Pourtant, en raison des contraintes anatomiques de la crosse aortique, l'expérience endovasculaire avec des dispositifs qui traversent la crosse et se déploient dans la zone 0 reste limitée. Nous rapportons la première expérience canadienne de l'endoprothèse thoracique RelayBranch avec déploiement (Terumo Aortic, Sunrise, FL) en zone 0 pour une réparation endovasculaire totale de la crosse aortique chez un patient présentant un risque très élevé de reprise de chirurgie ouverte. Nous décrivons le déploiement en toute sécurité du dispositif et le traitement réussi d'une endofuite de type 1A. Enfin, nous examinons les caractéristiques du système RelayBranch qui limitent les difficultés liées au déploiement du dispositif dans la crosse aortique.

In-hospital outcomes and long-term survival of women of childbearing age with aortic dissection.

OBJECTIVE: In the present study, we defined the outcomes and effects of pregnancy in a cohort of women of childbearing age with acute aortic dissection (AAD). METHODS: We reviewed our database of AAD to identify all eligible female patients. Women aged <45 years were included. Data on pregnancy timing with respect to the occurrence of dissection, the demographic data, dissection extent, dissection treatment, dissection-related outcomes, overall maternal and fetal mortality, and genetic testing results were analyzed. RESULTS: A total of 62 women aged <45 years had presented to us with AAD from 1999 to 2017. Of the 62 women, 37 (60%) had had a history of pregnancy at AAD. Of these 37 patients, 10 (27%) had had a peripartum aortic dissection, defined as dissection during pregnancy or within 12 months postpartum. Of the 10 AADs, 5 were type A and 5 were type B. Three patients had presented with AAD during pregnancy (one in the second and two in the third trimester). Five patients (50%) had developed AAD in the immediate postpartum period (within 3 months) and two (20%) in the late postpartum period. For the immediate postpartum AADs (<3 months), four of the five patients delivered via cesarean section. Of these 10 peripartum AADs, 3 (30%) had occurred in patients with known Marfan syndrome. In-hospital mortality for those with peripartum AAD was 10% (1 of 10). Fetal mortality was 20% (2 of 10). CONCLUSIONS: The frequency of aortic dissection in women of childbearing age at our institution was low. However, pregnancy might increase the risk of those young women genetically predisposed to dissection events. From these data, this risk appears to be greatest in the immediate postpartum period, even for those who undergo cesarean section. Close clinical and radiographic surveillance is required for all women with suspected aortopathy, especially in the third trimester and early postpartum period.

Endovascular Repair of Ruptured Ascending Aorta Secondary to Embolized Transcatheter Aortic Valve.

Since its approval by the United States Food and Drug Administration in 2011, transcatheter aortic valve replacement has revolutionized the treatment of aortic valvular disease with a rapid increase in use. Potentially fatal aortic complications are rare, occurring in 0.2% to 1.1% of cases-all reported in the early perioperative period. We present a case of a late ascending aortic pseudoaneurysm with rupture secondary to erosion by an embolized transcatheter aortic valve occurring 6 years after implantation. The patient was successfully treated with a commercially available, off-the-shelf aortic endograft.

Contemporary Management of Aortic Arch Aneurysm.

The management of the aortic arch aneurysm is becoming increasingly complex and multidisciplinary. It has evolved since the first successful repair by DeBakey et al in 1957. After these initial repairs, the improvement in open surgical techniques, cardiopulmonary bypass, anesthesia, and perioperative care were the primary drivers of the decrease in morbidity and mortality associated with repair. The development of endovascular technology has spurred another revolution in the management of aortic arch aneurysms. In this review, we present a current appraisal and description of open surgical, hybrid, and endovascular techniques based on the literature. These techniques are varied and have different advantages and disadvantages, depending on patient anatomy and perioperative surgical risk. We provide an overview of the attributes of each technique and how they may be applied to individual cases. While each technique could not be discussed in detail in this report, it is clear that institutions must be able to proficiently offer the full spectrum of open, hybrid, and endovascular surgical techniques to treat this diverse condition. For low and intermediate risk patients, open surgery remains the gold standard. However, just as improvements in technique, monitoring and perioperative care led to progress in open repair, similar advancements in endograft technology, anatomical customization, and embolic protection will expand the use of endovascular repair. As the management of the condition becomes increasingly nuanced and multidisciplinary, centers must be equipped to offer a variety of techniques with high fidelity and adaptability to each unique patient.

Differential Interactions between Tat-specific redox enzyme peptides and their chaperones.

The twin-arginine translocase (Tat) system is used by many bacteria to move proteins across the cytoplasmic membrane. Tat substrates are prefolded and contain a conserved SRRxFLK twin-arginine (RR) motif at their N termini. Many Tat substrates in Escherichia coli are cofactor-containing redox enzymes that have specific chaperones called redox enzyme maturation proteins (REMPs). Here we characterized the interactions between 10 REMPs and 15 RR peptides of known and predicted Tat-specific redox enzyme subunits. A combination of in vitro and in vivo experiments demonstrated that some REMPs were specific to a redox enzyme(s) of similar function, whereas others were less specific and bound peptides of unrelated enzymes. Results from Biacore surface plasmon resonance (SPR) and bacterial two-hybrid experiments identified interactions in addition to those found in far-Western experiments, suggesting that conformational freedom and/or other cellular factors may be required. Furthermore, we show that the interaction of the two prevents both from being proteolytically degraded in vivo, and kinetic data from SPR show up to 10-fold-tighter binding to the expected RR substrate when multiple binding partners existed. Investigations using full-length sequences of the RR proteins showed that the mature portion for some redox enzyme subunits is required for detection of the interactions. Sequence alignments among the REMPs and RR peptides indicated that homology between the REMPs and the hydrophobic regions following the RR motifs in the peptides correlates to cross-recognition.

Small multidrug resistance proteins: a multidrug transporter family that continues to grow.

The small multidrug resistance (SMR) protein family is a bacterial multidrug transporter family. As suggested by their title, SMR proteins are composed of four transmembrane alpha-helices of approximately 100-140 amino acids in length. Since their designation as a family, many homologues have been identified and characterized both structurally and functionally. In this review the topology, structure, drug resistance, drug binding, and transport mechanisms of the entire SMR protein family are examined. Additionally, updated bioinformatic analysis of predicted and characterized SMR protein family members was also conducted. Based on SMR sequence alignments and phylogenetic analysis of current members, we propose that this small multidrug resistance transporter family should be expanded into three subclasses: (i) the small multidrug pumps (SMP), (ii) suppressor of groEL mutation proteins (SUG), and a third group (iii) paired small multidrug resistance proteins (PSMR). The roles of these three SMR subclasses are examined, and the well-characterized members, such as Escherichia coli EmrE and SugE, are described in terms of their function and structural organization.