Reoperative aortic root surgery: single-center long-term outcomes and literature review.

Background and Objective: Reoperative aortic root surgery has become more and more common over the years and is considered high-risk, with significantly worse outcomes compared to first-procedure root surgery. At our institution, this kind of surgery is frequently performed. The aim of the present review is to describe currently available literature on reoperative surgery on the aortic root in terms of patients' population, indications for surgery and outcomes and to present our center's experience on the matter. Methods: A literature review was performed in order to identify pertinent studies. They were then compared and described. We also described preoperative characteristics, operative strategies and outcomes of all the patients who underwent redo aortic root surgery from January 1986 to December 2022 at our center. Key Content and Findings: Our literature review identified 12 pertinent studies, with a total of 16,627 considered patients. The most frequent indications for redo surgery were endocarditis (35.5%), aneurysm, dissection and pseudoaneurysm. Mean cardiopulmonary bypass (CPB) and cross-clamp times were 218 and 152 minutes, respectively. In-hospital mortality was 12%. When analyzing our center's data, 344 procedures were identified. Aortic root dilation was the most frequent indication (36.9%). Mean CPB and cross-clamp times were 218.0±78.8 and 158.2±49.7 minutes, respectively. In-hospital mortality was 9.6%. Survival at 5 and 15 years was 76.1% and 51.4% respectively. Freedom from further aortic reintervention was 88.1% after 5 years and 64.9% after 15 years. Conclusions: Reoperative aortic root surgery is a difficult cardiac procedure which is linked to significantly higher mortality than first-time root replacement. If it is performed by experienced surgeons with a careful preoperative planning its result can still be satisfactory. Our results showed acceptable rates of mortality and reinterventions at follow-up. Endocarditis, however, was linked to worse outcomes.

Is surgical risk of aortic arch aneurysm repair underestimated? A novel perspective based on 30-day versus 1-year mortality.

OBJECTIVES: The decision to undergo aortic aneurysm repair balances the risk of operation with the risk of aortic complications. The surgical risk is typically represented by perioperative mortality, while the aneurysmal risk relates to the 1-year risk of aortic events. We investigate the difference in 30-day and 1-year mortality after total arch replacement for aortic aneurysm. METHODS: This was an international two-centre study of 456 patients who underwent total aortic arch replacement for aneurysm between 2006 and 2020. Our primary end-point of interest was 1-year mortality. Our secondary analysis determined which variables were associated with 1-year mortality. RESULTS: The median age of patients was 65.4 years (interquartile range 55.1-71.1) and 118 (25.9%) were female. Concomitantly, 91 (20.0%) patients had either an aortic root replacement or aortic valve procedure. There was a drop in 1-year (81%, 95% confidence interval (CI) 78-85%) survival probability compared to 30-day (92%, 95% CI 90-95%) survival probability. Risk hazards regression showed the greatest risk of mortality in the first 4 months after discharge. Stroke [hazard ratio (HR) 2.54, 95% CI (1.16-5.58)], renal failure [HR 3.59 (1.78-7.25)], respiratory failure [HR 3.65 (1.79-7.42)] and reoperation for bleeding [HR 2.97 (1.36-6.46)] were associated with 1-year mortality in patients who survived 30 days. CONCLUSIONS: There is an increase in mortality up to 1 year after aortic arch replacement. This increase is prominent in the first 4 months and is associated with postoperative complications, implying the influence of surgical insult. Mortality beyond the short term may be considered in assessing surgical risk in patients who are undergoing total arch replacement.

Frozen elephant trunk technique using hybrid grafts: 15-year outcomes from a single-centre experience.

OBJECTIVES: The purpose of the study is to compare the short- and long-term outcomes of the frozen elephant trunk (FET) technique based on 2 different hybrid grafts implanted from January 2007 to July 2022. METHODS: The study includes patients who underwent an elective or emergency FET procedure. Short-term, long-term mortality and freedom from thoracic endovascular aortic repair (TEVAR) were the primary end points. Analyses were carried out separately for the periods 2007-2012 and 2013-2022. RESULTS: Of the 367 enrolled, 49.3% received E-Vita Open implantation and 50.7% received Thoraflex Hybrid implants. Overall mean age was 61 years [standard deviation (SD) = 11] and 80.7% were male. The average annual volume of FET procedures was 22.7 cases/year. Compared to E-Vita Open, patients implanted with Thoraflex Hybrid grafts were more likely to receive distal anastomosis in zone 2 (68.3% vs 11.6%, P < 0.001) with a shorter stent portion, mean = 103mm (SD = 11.3) vs mean = 149 mm (SD = 12.7; P < 0.001) and they underwent a reduced visceral ischaemia time, mean = 42.5 (SD = 14.2) vs mean= 61.0 (SD = 20.2) min, P < 0.001. In the period 2013-2022, overall survival at 1, 2 and 5 years was 74.8%, 72.5% and 63.2% for Thoraflex and 73.2%, 70.7% and 64.1% for E-Vita, without significant differences between groups (log-rank test = 0.01, P = 0.907). Overall freedom from TEVAR at 1, 2 and 5 years was 66.7%, 57.6% and 39.3% for Thoraflex and 79%, 69.7% and 66% for E-Vita, with significant differences between groups (log-rank test = 5.28, P = 0.029). In a competing risk analysis adjusted for chronic/residual aortic syndromes and stent diameter, the Thoraflex group was more likely to receive TEVAR during follow-up (subdistribution hazard ratio SHR = 2.12, 95% confidence interval 1.06-4.22). CONCLUSIONS: The FET technique addresses acute and chronic arch disease with acceptable morbidity and mortality. Downstream endovascular reinterventions are very common during follow-up.

Frozen elephant trunk in acute aortic dissection: a literature review.

Background: Acute aortic dissection is a life-threatening condition that requires urgent surgical treatment. The frozen elephant trunk (FET) technique, including the Thoraflex hybrid prosthesis, has emerged as an effective strategy for treating complex aortic pathologies. With the widespread application of the FET technique, it continues to evolve, aiming to simplify procedures and reduce complications. These advancements provide improved outcomes and help save lives in patients with acute aortic dissection. Methods: For this review, PubMed databases were utilized from inception to March 2023. A descriptive approach was employed to identify and present the evidence regarding the application of the FET technique in acute settings and its clinical implications on the postoperative course. Results: In the reviewed studies, FET was a commonly used treatment approach for acute type A aortic dissection. A comprehensive analysis of 12 studies, comprising over 4056 FET procedures, revealed varying rates of early mortality (up to 21.1%), perioperative stroke (ranging from 2.7 to 18.0%), and spinal cord ischemia (ranging from 0 to 8.2%). During the follow-up period, which ranged from 6 to 108 months, the mortality rate was reported to be as high as 38%. Conclusions: The surgical management of acute aortic dissection remains challenging, but FET has shown promising results. Experienced teams have achieved acceptable in-hospital mortality and stroke rates, along with a lower risk of spinal cord injury compared to conventional repair. Furthermore, the FET technique has demonstrated positive alterations in the structure of the distal aorta, potentially improving long-term survival and reducing the necessity for future procedures.

Staging TEVAR after FET - an exception or the rule?

Purpose: Frozen elephant trunk (FET) was born as an ideal one-step procedure to treat complex arch and descending thoracic aorta pathology. It was then proved that it frequently needs reintervention, which can often be performed by thoracic endovascular aortic repair (TEVAR) extension since FET provides a safe proximal landing zone. We hereby describe our experience in TEVAR extension after FET, its main indications, technique, and outcomes. Methods: Between 2007 and 2022, 371 patients underwent FET at our center. Of these, 119 needed TEVAR extension. Some required more than one TEVAR, with a total of 154 procedures. The preoperative characteristics, indications, and outcomes were analyzed retrospectively. Results: Of 154 TEVAR procedures, 15 were performed in an urgent setting. Mean time from FET to TEVAR was 22,2 ± 28,73 months. Two patients died in the operating room; no others died during the hospital stay. Survival after 1, 2, 5, and 10 years was 96.2%, 93.9%, 90.1%, and 70.5% respectively. There was no statistically significant difference in the rates of TEVAR extension for patients in which a Thoraflex™ vs E-vita™ graft was used, nor for zone 2 vs zone 3 anastomosis and stent length. Conclusion: Though TEVAR extension is often required after FET, it is a safe and effective procedure with excellent post-operative outcomes in the short-, mid-, and long-term and allows successful treatment of complex aortic pathologies. Rigorous and specialized follow-up after FET is central to identify the right moment to intervene.

Survival and reoperation in acute aortic syndromes-a single-centre experience of 912 patients.

OBJECTIVES: Acute aortic syndromes are associated with poor outcomes, despite diagnostic and therapeutic advances. We analysed trends in volumes and outcomes from 2000 to 2021. METHODS: The study population includes 494 type A acute aortic syndromes (TAAAS) (54.2%) and 418 type B acute aortic syndromes (TBAAS) (45.8%). Primary outcomes were in-hospital mortality, long-term survival and freedom from aortic reoperation. RESULTS: Regardless the type of acute aortic syndrome, patient volumes increased over time. Patients with TBAAS were older, more likely to have comorbid conditions and previous cardiac surgery (P < 0.001), while cerebrovascular accidents were more frequent in TAAAS (P < 0.05). Among TAAAS, 143 (28.9%) required total arch and 351 (71.1%) hemiarch replacement. TBAAS management was medical therapy in 182 (43.5%), endovascular in 198 (47.4%) and surgical in 38 (9.1%) cases. Overall in-hospital mortality was 14.6% [18.2% in TAAAS (95% confidence interval (CI) 14.4-21.2%) vs 10.7% in TBAAS (95% CI 7.8%-13.7%); P = 0.0027]. After propensity score adjustment, in-hospital mortality exhibited a significantly decreasing trend from 2000 to 2021 (P < 0.001) in TAAAS and TBAAS. 1-, 5- and 10-year survival was 74.2%, 62.2% and 45.5% in TAAAS and 75.4%, 60.7% and 41.0% in TBAAS (P = 0.975), with no differences among treatment strategies. The adjusted cumulative reoperation risk at 10 years was more than two-fold in TBAAS versus TAAAS (9.5% vs 20.5%, hazard ratio (HR) = 2.30, 95% I 1.31-4.04). CONCLUSIONS: In the last decades, better patient triage and surgical/endovascular techniques led to substantial improvements in the management of acute aortic syndrome, with reduction in early mortality and reoperation rate. However, long-term mortality is still >50%.

Distal stent graft-induced new entry (dSINE) after frozen elephant trunk: a scoping review.

Background: The introduction of hybrid total arch replacement with the frozen elephant trunk (FET) technique has improved the field of aortic surgery by allowing single-stage treatment of complex aortic pathologies. Although FET has been associated with favorable aortic remodeling, it is also associated with the potential development of distal stent graft-induced new entries (dSINEs). The aim of our review is to collect data about the incidence and the supposed conditions for the occurrence of dSINE after total hybrid arch replacement with FET technique. Methods: The literature review was performed using PubMed databases from inception to January 2022. A descriptive approach to detect and display supposed risk factors and predictors for dSINE occurrence has been adopted. Results: Eight studies summarized the state-of-the-art of dSINE in a total number of 544 FET procedures performed to treat acute and chronic aortic dissections. The scoping review showed dSINEs occurrence in 69 patients (12.7%). The mean time between surgery and the diagnosis ranged from 12.6 to 30.6 months. Most patients that developed dSINE received endovascular treatment, whereas a couple of them needed open surgery. According to our experience, from January 2007 to December 2021, in 225 FET procedures a total of 54 cases of dSINE, both with Thoraflex and E-vita grafts have been detected. The mean time between the surgical procedure and the diagnosis was 27.2±33.6 months. Conclusions: dSINEs are frequent complications after FET. Although not emergent, they require proper treatment. Due to dSINE's asymptomatic nature and potential harm, a rigorous follow-up including angio-computed tomography (CT) should be planned.

Aortic tissue pathology in reoperative post-dissection repair following prior use of BioGlue.

AIM: The benefits of BioGlue as a surgical adjunct in aortic procedures have been demonstrated in several studies, but limited information is available regarding the associated histopathological findings of aortic tissue at the time of reoperation. The objective of this study was to assess, at reoperation, the histopathological characteristics of aortic tissue which has had BioGlue applied during a previous surgery. METHODS: This prospective, single-center, single-arm study enrolled patients who were undergoing aortic reoperation and who had BioGlue used during previous aortic surgery. Histopathological assessment of aortic specimens obtained intraoperatively was performed on tissue that would have been removed independent of subject participation in the study. RESULTS: A total of 11 patients were enrolled and based on gross assessment, excessive amounts of BioGlue had been applied during the initial surgery in 36.4% of cases. The samples with the greatest amount of residual BioGlue demonstrated moderate to marked inflammatory responses, while the remaining samples demonstrated minimal to moderate inflammatory responses. Calcification of residual BioGlue was noted in 4 cases. Substantial medial degeneration was associated with suture line dehiscence in 4 cases, some of which had a large quantity of residual BioGlue. No evidence of suture degradation was observed. CONCLUSIONS: Cases with surgical anastomosis dehiscence were associated with substantial medial degeneration. While no histologic findings directly linked BioGlue to these degenerative changes, a contributory role cannot be excluded. Following the manufacturer's instructions for appropriate application of BioGlue is crucial to prevent potential complications.

How much should be covered a type B aortic dissection? Just do it, but don't forget about spinal cord protection.

Revascularization of the left subclavian artery (LSA) is considered a method of spinal cord protection from ischemia during thoracic endovascular aortic repair (TEVAR). Coverage of the artery of Adamkiewicz with TEVAR is usually well tolerated because of collateral pathways to this vessel, but on the other side, the LSA is crucial in this regard since it represents the primary source of collateral pathways. In our commentary, we wish to focus the discussion on the LSA revascularization and about the complexity of the anatomy of spinal cord supply in order to underline what have been already studied, analyzed, and recommended from the current guidelines.

BioGlue® is not associated with polypropylene suture breakage after aortic surgery.

Objective: We have encountered broken or damaged polypropylene sutures (Prolene®) at the anastomotic sites during aortic reoperations. Because a surgical sealant, bovine serum albumin-glutaraldehyde (BioGlue®), was used in previous aortic surgery in some of these cases, we undertook this in vitro study to evaluate whether the use of BioGlue® was associated with breakage of polypropylene sutures at the aortic anastomosis. Materials and methods: The broken polypropylene sutures, anastomotic sites and aortic tissue at the location of suture breakage were visually inspected and evaluated intraoperatively. Six human cadaveric aortic samples were incised circumferentially and anastomosed proximally to a valved conduit with running 4-0 polypropylene sutures (Prolene®). In the test group (n = 3), BioGlue® was applied directly to the Prolene® sutures at the anastomotic sites, while in the control group (n = 3) the anastomoses were not sealed with any surgical adhesive. The six samples were immersed in Dulbecco's phosphate buffered saline solution and mounted on a M-6 Six Position Heart Valve Durability Testing System and tested up to 120 million cycles for a 2-year period. During and upon completion of the testing, the integrity of Prolene® sutures, the anastomosis and aortic tissues was regularly assessed by visual inspection. Results: Intraoperative findings included a stretched and thin aortic wall (some with thrombus), a small cleft between the aortic tissue and the Dacron vascular graft. An excessive amount of BioGlue® was often found around the anastomosis, with cracking material, but no signs of mechanical damage were observed in these cases. Upon visual inspection during and after in vitro testing, there was no apparent damage to the polypropylene sutures on the interior or exterior of the aortic anastomoses in any of the samples. No difference was observed in the physical integrity of the polypropylene sutures at anastomotic lines, the anastomoses and aortic tissues between the test and control samples. Conclusions: The results of this study suggest that the use of BioGlue® was not associated with breakage of the polypropylene sutures at the anastomotic sites after aortic dissection repair.