Perioperative Mass Transfusion Affects In-Hospital but Not Follow-Up Survival in Patients with Acute Type A Aortic Dissection.

Background and Objectives: The aim of this study was to analyze the influence of mass transfusion on the postoperative outcome and survival in patients presenting with acute Type A aortic dissection. Materials and Methods: Between 2002 and 2020, a total of 505 patients were surgically treated for an acute Type A aortic dissection. Mass transfusion was defined as the peri- and postoperative replacement by transfusion of 10 units. Patient characteristics and outcomes were analyzed and compared between patients with and without mass transfusion. Results: Mass transfusion occurred in 105 patients (20%). The incidences of symptomatic coronary malperfusion (p = 0.017) and tamponade (p = 0.043) were higher in patients with mass transfusion. There was no statistically significant difference in the distal extension of the aortic dissection between the two groups. A valved conduit was significantly more common in patients with mass transfusion (p = 0.007), while the distal aortic repair was similar between the two groups. Cardiopulmonary bypass time (p < 0.001), cross clamp time (p < 0.001) and in-hospital mortality were significantly higher in patients with mass transfusion (p < 0.001), but the survival after discharge (landmark-analysis) showed equal survival between patients with and without mass transfusion (log rank: p = 0.4). Mass transfusion was predictive of in-hospital mortality (OR: 3.308, p < 0.001) but not for survival after discharge (OR: 1.205, p = 0.661). Conclusions: Mass transfusion is necessary in many patients with acute Type A aortic dissection. These patients present sicker and require longer surgery. However, mass transfusion does not influence survival after discharge.

Training in Aortic Arch Surgery as a Blueprint for a Structured Educational Team Approach: A Review.

Background and objectives: The treatment of pathologies of the aortic arch is a complex field of cardiovascular surgery that has witnessed enormous progress recently. Such treatment is mainly performed in high-volume centres, and surgeons gain great experience in mastering potential difficulties even under emergency circumstances, thereby ensuring the effective therapy of more complex pathologies with lower complication rates. As the numbers of patients rise, so does the need for well-trained surgeons in aortic arch surgery. But how is it possible to learn surgical procedures in a responsible way that, in addition to surgical techniques, also places particular demands on the overall surgical management such as perfusion strategy and neuro-protection? This is why a good training programme teaching young surgeons without increasing the risk for patients is indispensable. Our intention was to highlight the most challenging aspects of aortic arch surgery teaching and how young surgeons can master them. Materials and Methods: We analysed the literature to find out which methods are most suitable for such teaching goals and what result they reveal when serving as teaching procedures. Results: Several studies were found comparing the surgical outcome of young trainees with that of specialists. It was found that the results were comparable whether the procedure was performed by a specialist or by a trainee assisted by the specialist. Conclusions: We thus came to the conclusion that even for such a complex type of intervention, the responsible training of young surgeons by experienced specialists is possible. However, it requires a clear strategy and team approach to ensure a safe outcome for the patient.

Thoracic aortic emergencies involving the aortic arch: An integrated cardiovascular surgical treatment approach.

Thoracic aortic emergencies involving the aortic arch are potentially fatal conditions that require the entire surgical repertoire of conventional surgery, such as complete aortic arch replacement using the frozen-elephant-trunk technique, through hybrid procedures, to full surgical endovascular options with conventional or delivered/fenestrated stent-grafts. An interdisciplinary aortic team should choose the optimal treatment of the pathologies of the aortic arch, considering the morphology of the entire aorta, from the root to beyond the bifurcation, as well as the clinical comorbidities. The treatment goal is a complication-free postoperative result and lasting freedom from aortic reinterventions. Irrespective of the selected therapy method, patients should then be connected to a specialized aortic outpatient clinic. The aim of this review was to provide an overview of pathophysiology and current treatment options in emergencies of the thoracic aorta, also involving the aortic arch. We wanted to summarize the preoperative considerations, intraoperative settings, and strategies, as well the postoperative follow-up.

Practice of neuromonitoring in open and endovascular thoracoabdominal aortic repair-an international expert-based modified Delphi consensus study.

OBJECTIVES: Spinal cord injury is detrimental for patients undergoing open or endovascular thoracoabdominal aortic aneurysm (TAAA) repair. The aim of this survey and of the modified Delphi consensus was to gather information on current practices and standards in neuroprotection in patients undergoing open and endovascular TAAA. METHODS: The Aortic Association conducted an international online survey on neuromonitoring in open and endovascular TAAA repair. In a first round an expert panel put together a survey on different aspects of neuromonitoring. Based on the answers from the first round of the survey, 18 Delphi consensus questions were formulated. RESULTS: A total of 56 physicians completed the survey. Of these, 45 perform open and endovascular TAAA repair, 3 do open TAAA repair and 8 do endovascular TAAA repair. At least 1 neuromonitoring or protection modality is utilized during open TAAA surgery. Cerebrospinal fluid (CSF) drainage was used in 97.9%, near infrared spectroscopy in 70.8% and motor evoked potentials or somatosensory evoked potentials in 60.4%. Three of 53 centres do not utilize any form of neuromonitoring or protection during endovascular TAAA repair: 92.5% use CSF drainage; 35.8%, cerebral or paravertebral near infrared spectroscopy; and 24.5% motor evoked potentials or somatosensory evoked potentials. The utilization of CSF drainage and neuromonitoring varies depending on the extent of the TAAA repair. CONCLUSIONS: The results of this survey and of the Delphi consensus show that there is broad consensus on the importance of protecting the spinal cord to avoid spinal cord injury in patients undergoing open TAAA repair. Those measures are less frequently utilized in patients undergoing endovascular TAAA repair but should be considered, especially in patients who require extensive coverage of the thoracoabdominal aorta.

Experience with "Select Crowd Review" in Peer Review for The Thoracic and Cardiovascular Surgeon: 1-Year Experience.

OBJECTIVE: To evaluate the experience with a new peer review method, "Select Crowd Review" (SCR): anonymized PDFs of manuscripts are accessible to a reviewer crowd via an online platform. It has access for 10 days to enter anonymized comments directly into the manuscript. A SCR-Editor summarizes the annotations, giving a recommendation. Both reviewed PDF and summary are sent back to authors. Upon submission, authors are given a choice to accept or decline SCR. DESIGN: All manuscript submissions since introduction in July 2021 until July 2022 were analyzed regarding acceptance and quality. Manuscripts were sent to a crowd of 45 reviewers and regular double-blinded peer review at the same time. Efficiency and performance of the crowd's reviews were compared with those of regular review. For thoracic manuscripts, a crowd was not yet available. RESULTS: SCR was accepted by the authors for 73/179 manuscripts (40.8%). After desk rejections, 51 cardiac manuscripts entered SCR. For five manuscripts, the crowd did not respond. In all remaining papers, the crowd's recommendation concurred with that of the normal reviewers. Regular peer review took up to 6 weeks. Twelve manuscripts underwent repeated SCR after revision. A median of 2 (0-9) crowd members sent in reviews. In revisions, average response was one reviewer responding. CONCLUSION: SCR encountered good acceptance by authors. As the first experience showed concordant recommendations compared with traditional review, we have extended SCR to thoracic manuscripts for more experience. SCR may become the sole review method for eligible manuscripts. Efficiency should be increased, especially for re-review of revisions.

Concomitant aortic root replacement during frozen elephant trunk implantation does not increase perioperative risk.

OBJECTIVES: Our aim was to evaluate the risk of concomitant aortic root replacement during frozen elephant trunk (FET) total arch replacement. METHODS: Between March 2013 and February 2021, 303 patients underwent aortic arch replacement using the FET technique. Patient characteristics, intra- and postoperative data were compared between patients with (n = 50) and without (n = 253) concomitant aortic root replacement (implantation of a valved conduit or using the reimplantation valve-sparing technique) after propensity score matching. RESULTS: After propensity score matching, there were no statistically significant differences in preoperative characteristics including the underlying pathology. There was no statistically significant difference regarding arterial inflow-cannulation or concomitant cardiac procedures, while cardiopulmonary bypass (P < 0.001) and aortic cross-clamp (P < 0.001) times were significantly longer in the root replacement group. Postoperative outcome was similar between the groups and there were no proximal reoperations in the root replacement group during follow-up. Root replacement was not predictive for mortality (P = 0.133, odds ratio: 0.291) in our Cox regression model. There was no statistically significant difference in overall survival (log rank: P = 0.062). CONCLUSIONS: Concomitant FET implantation and aortic root replacement prolongs operative times but does not influence postoperative outcomes or increase operative risk in an experienced high-volume centre. The FET procedure did not appear to be a contraindication for concomitant aortic root replacement even in patients with borderline indications for aortic root replacement.

Similarities, differences and unmet needs regarding prosthetic materials in aortic arch replacement using the frozen elephant trunk technique: a review.

The constant improvement of operative techniques offers the possibility of treating an increasing number of patients with complex acute and chronic thoracic aortic pathologies involving the aortic arch. Reliable and durable prosthetic material forms the platform for these approaches. Besides the most important properties like impermeability for blood, infection and thrombotic resistance, there are also properties which are not seen at first glance but can nevertheless play a key role in the healing process and long-term results, such as endothelialization and immunostimulation. To ensure the best possible properties of the graft, different variables of the grafts are continuously developed. Beside the choice of material and the weaving technique, Dacron sealing with gelatin is in clinical use for many years but is still being discussed. Collecting clinical experiences with sealed and unsealed grafts in aortic arch replacement led to the conclusion that blood loss through the prosthesis, especially in the early phase after the implantation of the graft, is lowered by gelatin sealing. Furthermore, binding of antimicrobiotic and antithrombotic agents to the collagen are promising approaches to a better prevention of these dreaded complications. More research examining the healing process of the prosthesis is needed in order to find out more about the influence of the prosthesis sealing.

Downstream thoracic endovascular aortic repair following the frozen elephant trunk procedure.

The frozen elephant trunk technique has become a well-established treatment option for patients presenting all thoracic aortic pathologies including acute and chronic dissection, aortic aneurysms and even penetrating aortic ulcers involving the aortic arch and descending aorta. Nevertheless, there is a significant incidence of and risk for distal aortic reinterventions after the frozen elephant trunk. Indications mainly include a planned staged approach, diameter progression of downstream aortic segments and the development of distal stent-graft induced new entries (dSINEs). Endovascular stent-graft extension through conventional thoracic endovascular aortic repair (TEVAR) is a relatively simple and safe method to address any pathologies in the remaining descending thoracic aorta up to the level of the coeliac trunk. In fact, the frozen elephant trunk stent-graft provides an ideal proximal landing zone for any endovascular stent-graft extension. Postoperative outcomes are very promising with very low reported in-hospital mortality and morbidity. In case this 2-staged-approach fails to stabilize the remaining aorta, a 3-step procedure, namely open thoracoabdominal aortic replacement, is simplified because the anastomosis site has moved distally. Follow-up of all patients, following frozen elephant trunk implantation or distal stent-graft extension, is mandatory, ideally in an outpatient clinic dedicated to the aorta in order to identify disease progression or to detect any complications as soon as possible.

Postoperative In-Stent Thrombus Formation Following Frozen Elephant Trunk Total Arch Repair.

Objectives: Our aim was to investigate the occurrence and clinical consequence of postoperative in-stent thrombus formation following the frozen elephant trunk (FET) procedure. Methods: Postoperative computed tomography angiography (CTA) scans of all 304 patients following the FET procedure between 04/2014 and 11/2021 were analysed retrospectively. Thrombus size and location were assessed in multiplanar reconstruction using IMPAX EE (Agfa HealthCare N.V., Morstel, Belgium) software. Patients' characteristics and clinical outcomes were evaluated between patients with and without thrombus formation. Results: During the study period, we detected a new postoperative in-stent thrombus in 19 patients (6%). These patients were significantly older (p = 0.009), predominantly female (p = 0.002) and were more commonly treated for aortic aneurysms (p = 0.001). In 15 patients (79%), the thrombi were located in the distal half of the FET stent-graft. Thrombus size was 18.9 mm (first quartile: 12.1; third quartile: 33.2). Distal embolisation occurred in 4 patients (21%) causing one in-hospital death caused by severe visceral ischaemia. Therapeutic anticoagulation was initiated in all patients. Overstenting with a conventional stent-graft placed within the FET stent-graft was the treatment in 2 patients (11%). Outcomes were comparable both groups. Female sex (p = 0.005; OR: 4.289) and an aortic aneurysm (p = 0.023; OR: 5.198) were identified as significant predictors for thrombus development. Conclusion: Postoperative new thrombus formation within the FET stent-graft is a new, rare, but clinically highly relevant event. The embolisation of these thrombi can result in dismal postoperative outcomes. More research is therefore required to better identify patients at risk and improve perioperative treatment.

Distal Aortic Failure Following the Frozen Elephant Trunk Procedure for Aortic Dissection.

Background: Aim of this study was to report and to identify risk factors for distal aortic failure following aortic arch replacement via the frozen elephant trunk (FET) procedure. Methods: One hundred eighty-six consecutive patients underwent the FET procedure for acute and chronic aortic dissection. Our cohort was divided into patients with and without distal aortic failure. Distal aortic failure was defined as: (I) distal aortic reintervention, (II) aortic diameter dilatation to ≥ 6 cm or > 5 mm growth within 6 months, (III) development of a distal stent-graft-induced new entry (dSINE) and/or (IV) aortic-related death. Preoperative, intraoperative, postoperative and aortic morphological data were analyzed. Results: Distal aortic failure occurred in 88 (47.3%) patients. Forty-six (24.7%) required a distal reintervention, aortic diameter dilatation was observed in 9 (4.8%) patients, a dSINE occurred in 22 (11.8%) patients and 11 (6.4%) suffered an aortic-related death. We found no difference in the number of communications between true and false lumen (p = 0.25) but there were significantly more communications between Ishimaru zone 6-8 in the distal aortic failure group (p = 0.01). The volume of the thoracic descending aorta measured preoperatively and postoperatively within 36 months afterward was significantly larger in patients suffering distal aortic failure (p < 0.001; p = 0.011). Acute aortic dissection (SHR 2.111; p = 0.007), preoperative maximum descending aortic diameter (SHR 1.029; p = 0.018) and preoperative maximum aortic diameter at the level of the diaphragm (SHR 1.041; p = 0.012) were identified as risk factors for distal aortic failure. Conclusion: The incidence and risk of distal aortic failure following the FET procedure is high. Especially those patients with more acute and more extensive aortic dissections or larger preoperative descending aortic diameters carry a substantially higher risk of developing distal aortic failure. The prospective of the FET technique as a single-step treatment for aortic dissection seems low and follow-up in dedicated aortic centers is therefore paramount.

Endovascular treatment of traumatic aortic rupture using iliac extension stent-grafts in patients with small aortic diameters.

OBJECTIVES: To evaluate outcomes after thoracic endovascular aortic repair in young patients sustaining traumatic blunt aortic injury (BAI) using iliac extension stent-grafts because of small aortic diameters measuring <24 mm. METHODS: Retrospective analysis regarding clinical presentation, trauma management, endovascular techniques and outcome of patients with a small descending aorta involving an iliac extension stent-graft to treat traumatic BAI. RESULTS: Among 48 patients who suffered a BAI and underwent thoracic endovascular aortic repair, 7 received iliac extension stent-grafts. They were 27.4/[standard deviation (SD): -13.1] years old and 6 out of 7 were male. The iliac extension stent-graft was used as distal stent-graft, and a thoracic stent-graft was used in most patients as proximal extension. We achieved overall technical success in all patients during a procedure lasting 92.6 (SD: 54.9) min. One patient died 2 days after the endovascular procedure of hypoxic brain injury, and another died after 17 days of liver failure. That patient had also suffered a spinal cord injury following the procedure, as the stent-graft had been deployed in Ishimaru Zone 2, and the carotid to subclavian bypass had to be omitted because of his critical condition. Control computed tomographic angiographs was available in 6 patients after 7.7 (SD: 5.1) days and showed no endoleak. The surviving patients were discharged after 18.4 (SD: 13.4) days. CONCLUSIONS: Treating traumatic BAI using iliac extension stent-grafts in young patients with small aortic diameters is feasible. We observed no mortality caused by the BAI or related to endovascular therapy within this small patient cohort.

Diameter Changes in Traumatic Aortic Injury: Implications for Stent-Graft Sizing.

OBJECTIVES: The aim of this study was to compare aortic diameters from admission computed tomography angiography (CTA) scans to postoperative aortic diameters in patients with traumatic aortic injury (TAI) and evaluate the influence of substantial blood loss on aortic diameter. METHODS: The aortic databases of two tertiary university centers were retrospectively screened for patients with TAI between February 2002 and February 2019. Concomitant organ injuries, bone fractures, blood loss, and clinical outcomes were evaluated. Aortic diameters were measured in CTA upon admission and were compared with the CTA before discharge at three different aortic levels (mid-ascending, 5 cm distal to the end of the stent graft, and at the celiac trunk level). RESULTS: We identified 45 patients, aged 43 (first quartile; third quartile [26; 55]) years with a TAI treated by thoracic endovascular aortic repair. The most frequent cause of TAI was a car accident (n = 24). Concomitant injuries were seen in all but one patient. Bone and pelvic fractures were seen in 40 (89%) and 15 (33%) patients, respectively. Type III aortic injury was present in 25 patients (56%). Increase of aortic diameter after stabilization was +1.7 mm (-0.6 mm; 2.5 mm; p = 0.004) at the mid-ascending aorta, +2.1 mm (0.2 mm; 3.8 mm; p < 0.001) 5 cm distal to the stent graft, and +1.5 mm (0.5 mm; 3.2 mm; p < 0.001) at the celiac trunk level. CONCLUSION: In patients with TAI, the aortic diameter is significantly reduced as compared with the aortic diameter at discharge. The reduction of aortic diameter might be caused by hemorrhagic shock and should be kept in mind for appropriate stent-graft sizing.

Impact of concomitant replacement of the ascending aorta in patients undergoing aortic valve replacement on operative morbidity and mortality.

OBJECTIVES: The aim of this study was to evaluate the impact of concomitant ascending aortic replacement on operative morbidity and mortality in patients undergoing aortic valve replacement (AVR). METHODS: We retrospectively analysed our institutional database for all patients undergoing elective isolated AVR and AVR with concomitant replacement of the ascending aorta between January 2009 and May 2020. Patients undergoing surgery for infective endocarditis or requiring hypothermic circulatory arrest were excluded. A 3:1 propensity matching was performed for 688 patients to compare isolated AVR (120 patients) with AVR + ascending aortic replacement (40 patients). RESULTS: There were significant differences in median cardiopulmonary bypass (CPB) time [92.5 (75-114) vs 118.5 (104-131) min; P < 0.001], median aortic cross-clamp time [65.0 (51.5-78.5) vs 84.5 (77-94) min; P < 0.001] and median intensive care unit stay [1 (1-3) vs 2 (1-6) days; P < 0.01]. There was no significant difference in the use of intraoperative and postoperative blood products, re-exploration for bleeding, postoperative atrial fibrillation, acute renal failure, incidence of stroke, perioperative myocardial infarction and 30-day mortality. CONCLUSIONS: Concomitant replacement of the ascending aorta significantly prolongs CPB and aortic clamp times but does not increase operative morbidity and mortality. Therefore, replacement of a dilated ascending aorta appears to be the most durable and safest treatment option in patients undergoing AVR with an aneurysmatic ascending aorta.

Morphology of the left subclavian artery: implications for single-branched endovascular aortic arch repair.

OBJECTIVES: Our goal was to evaluate the morphology of the aortic arch, focusing on the left subclavian artery (LSA), and to anticipate implications for single-branched endovascular aortic arch repair. METHODS: We performed a morphological analysis of computed tomography angiography scans of 322 patients between January 2002 and December 2018. Arch type and distance between arch vessels on the convexity were evaluated. We defined 3 morphological types: U-type distance between the left common carotid artery (LCCA) and LSA offspring >10 mm; V-type distance between the LCCA and LSA offspring <10 mm and W-type isolated left vertebral artery offspring from the aortic arch. RESULTS: Most patients presented a type III arch [50% (n = 161)]. The median distance from the brachiocephalic trunk offspring to the LCCA offspring measured 2.5 mm (2.0-3.0 mm) and that between the LCCA offspring and the LSA offspring was 6.5 mm (4.0-11.0 mm). We observed no significant difference based on the morphological type (V versus U versus W) in the brachiocephalic trunk-LCCA distance, but there were significant differences in the LCCA-LSA distance between types V and U (P < 0.001) and between types V and W (P < 0.001). Interestingly, we found no significant difference in the LCCA-LSA distance between types U and W. We noted a significant difference in the median diameter of the LSA according to U, V and W types: V type versus U type, 12.5 vs 13.5 mm (P = 0.033) as well as U type versus W type, 13.5 vs 10.5 mm (P < 0.001) and V type versus W type, 12.5 vs 10.5 mm (P < 0.002). The distances between the LSA offspring and left vertebral artery offspring between types U and V did not differ significantly. CONCLUSIONS: Our categorization of the U, V and W types of the LSA can help us anticipate shapes and distances and thereby function as an initial evaluation tool for predicting single branched endovascular aortic arch repair involving the LSA.