Standardizing clinical end points in aortic arch surgery: a consensus statement from the International Aortic Arch Surgery Study Group

Major adverse outcomes in patients with acute type A aortic dissection undergoing total arch replacement with frozen elephant trunk procedure

BACKGROUND

The objective of this investigation was to identify the risk factors linked to major adverse outcomes (MAO) subsequent to total arch replacement with frozen elephant trunk procedure (TAR+FET) surgery among patients diagnosed with acute type A aortic dissection (ATAAD). Additionally, the study aimed to elucidate the influence of these adverse outcomes on the long-term prognosis of the patients.

METHOD

670 ATAAD patients received the TAR+FET procedure. Multivariable logistic regression was used to investigate the risk factors associated with in-hospital MAO. Additionally, long-term survival outcomes were assessed through follow-up observations of all patients.

RESULTS

The overall in-hospital mortality was 4.33%. Among 670 patients, 169 patients (25.22%) developed postoperative MAO. Multivariate analysis showed that in-hospital MAO was positively associated with age (OR = 1.025, 95%CI: 1.005-1.045, P = 0.014), lower limb symptoms (OR = 2.562, 95%CI: 1.407-4.666, P = 0.002), involvement of coronary artery (OR = 2.027, 95%CI: 1.312-3.130, P = 0.001), involvement of left renal artery (OR = 1.998, 95%CI: 1.359-2.938, P < 0.001), CPB time (OR = 1.011, 95%CI: 1.007-1.015, P < 0.001) and WBC counts (OR = 1.045, 95%CI: 1.007-1.083, P = 0.019). MAO group showed a worse long-term prognosis than those non-MAO group (P = 0.002).

CONCLUSIONS

While TAR+FET can be an effective treatment option for ATAAD patients, careful patient selection and management are essential in minimizing the risk of MAO and ensuring long-term success.

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.

Development of a machine learning-based model to predict major adverse events after surgery for type A aortic dissection complicated by malnutrition

Objective

This study aims to develop a predictive model for the risk of major adverse events (MAEs) in type A aortic dissection (AAAD) patients with malnutrition after surgery, utilizing machine learning (ML) algorithms.

Methods

We retrospectively collected clinical data from AAAD patients with malnutrition who underwent surgical treatment at our center. Through least absolute shrinkage and selection operator (LASSO) regression analysis, we screened for preoperative and intraoperative characteristic variables. Based on the random forest (RF) algorithm, we constructed a ML predictive model, and further evaluated and interpreted this model.

Results

Through LASSO regression analysis and univariate analysis, we ultimately selected seven feature variables for modeling. After comparing six different ML models, we confirmed that the RF model demonstrated the best predictive performance in this dataset. Subsequently, we constructed a model using the RF algorithm to predict the risk of postoperative MAEs in AAAD patients with malnutrition. The test set results indicated that this model has excellent predictive efficacy and clinical applicability. Finally, we employed the Shapley additive explanations (SHAP) method to further interpret the predictions of this model.

Conclusion

We have successfully constructed a risk prediction model for postoperative MAEs in AAAD patients with malnutrition using the RF algorithm, and we have interpreted the model through the SHAP method. This model aids clinicians in early identification of high-risk patients for MAEs, thereby potentially mitigating adverse clinical outcomes associated with malnutrition.

One-year results of the Flowdynamics Dense Mesh Stent for residual dissection after proximal repair of stanford type A or type B aortic dissection: a multicenter, prospective, and randomized study

OBJECTIVE

Negative remodeling of the distal aorta following proximal repair for acute aortic dissection has garnered growing attention. This clinical scenario has spurred the development of techniques and devices. A multicenter, prospective, and randomized controlled study was conducted with the aim of confirming the safety and effectiveness of a newly-designed flowdynamics dense mesh stent for the treatment of residual dissection after proximal repair.

METHODS

Patients with nonchronic residual dissection affecting visceral branches were prospectively enrolled at three centers and randomly allocated to either the FDMS group or the control group. Primary endpoints encompassed all-cause and aortic-related mortality, while the patency of branch arteries is indeed a key focal metric. Morphological changes (diameter, area, and volume) were analyzed to demonstrate the therapeutic effect.

RESULTS

One hundred twelve patients were recruited in the clinical trial, and 103 patients completed the 12-month follow-up. The rate of freedom from all-cause and aortic-related death in the FDMS group was 94.64 and 100%, respectively. All visceral branches remained patent. The FDMS group exhibited a substantial expansion in TL and a notable shrinkage in FL at the planes below renal arteries (ΔArea TL : FDMS vs. Control, 0.74±0.46 vs. 0.34±0.66 cm 2 , P <0.001; ΔArea FL : FDMS vs. Control, -0.72±1.26 vs. -0.12±0.86 cm, P =0.01) and 5 cm below renal arteries (ΔArea TL : FDMS vs. Control, 1.06±0.75 vs. 0.16±0.63 cm 2 , P <0.001; ΔArea FL : FDMS vs. Control, -0.53±1.43 vs. -0.25±1.00 cm, P =0.27). Meanwhile, the FDMS group demonstrated an increase of 22.55±11.14 cm 3 in TL ( P <0.001) and a corresponding reduction of 21.94±11.77 cm 3 in FL ( P =0.08).

CONCLUSIONS

This newly-designed FDMS for endovascular repair of residual dissection following the proximal repair is demonstrated to be safe and effective at 12 months.

Inflammatory Trajectory and Anti-Inflammatory Pharmacotherapy in Frozen Elephant Trunk-Treated Acute Type I Aortic Dissection

Background

Acute DeBakey type I aortic dissection is associated with high morbidity and mortality. Little is known regarding the role of leukocyte trajectory in prognosis.

Methods

We included adult acute DeBakey type I aortic dissection patients with emergency frozen elephant trunk and total arch replacement in 2 cardiovascular centers (2020-2022). We used latent class mixed model to group patients according to their leukocyte patterns from hospital admission to the first 5 days after surgery. We investigated the association of leukocyte trajectory and 30-day and latest follow-up mortality (October 31, 2023), exploratorily analyzing the effects of ulinastatin treatment on outcome.

Results

Of 255 patients included, 3 distinct leukocyte trajectories were identified: 196 in group I (decreasing trajectory), 34 in group II (stable trajectory), and 25 in group III (rising trajectory). Overall, 30-day mortality was 25 (9.8%), ranging from 8.2% (16/196) in group I, 8.8% (3/34) in group II, to 24.0% (6/25) in group III (P for trend = .036). Group III was associated with higher mortality both at 30 days (adjusted hazard ratio, 3.260; 95% CI, 1.071-9.919; P = .037) and at the last follow-up (adjusted hazard ratio, 2.840; 95% CI, 1.098-7.345; P = .031) compared with group I.

Conclusions

Distinct and clinically relevant groups can be identified by analyzing leukocyte trajectories, and a rising trajectory was associated with higher short-term and midterm mortality.

Clinical predictive value of the age, creatinine, and ejection fraction score in patients in acute type A aortic dissection after total arch replacement

The age, creatinine, and ejection fraction (ACEF) score has been accepted as a predictor of poor outcome in elective operations. This study aimed to investigate the predictive value of ACEF score in acute type A aortic dissection (AAAD) patients after total arch replacement. A total of 227 AAAD patients from July 2021 and June 2022 were enrolled and divided into Tertiles 1 (ACEF ≤ 0.73), Tertiles 2 (0.73 < ACEF ≤ 0.95), and Tertiles 3 (ACEF > 0.95). Using inverse probability processing weighting (IPTW) to balance the baseline characteristics and compare the outcomes. Cox logistic regression was used to further evaluate the survival prediction ability of ACEF score. The in-hospital mortality was 9.8%. After IPTW, in the baseline characteristics reached an equilibrium, a higher ACEF score before operation still associated with higher in-hospital mortality. After 1 year follow-up, 184 patients (90.6%) survival. Multivariable analysis revealed that ACEF score (adjusted hazard ratio  1.68; 95% confidence interval 1.34-4.91; p = 0.036) and binary ACEF score (adjusted HR 2.26; 95% CI 1.82-6.20; p < 0.001) was independently associated with 1-year survival. In addition, net reclassification improvement (NRI) and integrated differentiation improvement (IDI) verified that the ACEF score and binary ACEF score is an accurate predictive tool in clinical settings. In conclusions, ACEF score could be considered as a useful tool to risk stratification in patients with AAAD before operation in daily clinical work.

The prognostic value of preoperative systemic inflammatory response index in predicting outcomes of acute type A aortic dissection patients underwent surgical treatment

Background

The systemic inflammatory response index (SIRI) is a novel inflammatory-immune biological marker that has prognostic value in various cardiovascular diseases. This study aims to investigate the relationship between SIRI and short-term and long-term prognosis in patients with acute type A aortic dissection (AAAD) underwent surgical treatment.

Methods

We conducted a retrospective analysis of patients with AAAD who underwent emergency surgical treatment at our center. Through multifactorial logistics regression analysis and cox proportional hazards regression analysis, we identified SIRI as an independent risk factor for major adverse events (MAEs) and long-term aorta-related adverse events (ARAEs) post-surgery. The optimal cutoff value of preoperative SIRI was determined using receiver operating characteristic (ROC) curve analysis, and patients were divided into low SIRI group and high SIRI group. The prognostic outcomes at different time points post-surgery for the two groups of patients were analyzed using Kaplan-Meier survival analysis, and the significance was determined by log-rank test.

Results

A total of 691 AAAD patients were included in this study. Among them, 50 patients (7.2%) died within 30 days post-surgery, and 175 patients (25.3%) experienced MAEs. A total of 641 patients were followed up, with an average follow-up time of 33.5 ± 17.5 months, during which 113 patients (17.6%) experienced ARAEs. The results of multifactorial logistics regression analysis and cox proportional hazards regression analysis showed that SIRI was an independent risk factor for postoperative MAEs (OR=3.148, 95%CI[1.650-6.006], p<0.001) and ARAEs (HR=2.248, 95%CI[1.050-4.809], p<0.037). Kaplan-Meier analysis demonstrated that the MAEs-free survival in the high SIRI group was significantly lower than that in the low SIRI group, and a similar trend was observed in the ARAEs-free survival during follow-up (log-rank test, p<0.001).

Conclusion

Preoperative SIRI is significantly associated with the short-term and long-term prognosis of AAAD patients underwent emergency open surgery, demonstrating its valuable prognostic value. Therefore, preoperative SIRI is a reliable biological marker that can serve as a valuable tool for preoperative risk stratification and decision management.

A predictive model for postoperative adverse outcomes following surgical treatment of acute type A aortic dissection based on machine learning

Acute type A aortic dissection (AAAD) has a high probability of postoperative adverse outcomes (PAO) after emergency surgery, so exploring the risk factors for PAO during hospitalization is key to reducing postoperative mortality and improving prognosis. An artificial intelligence approach was used to build a predictive model of PAO by clinical data-driven machine learning to predict the incidence of PAO after total arch repair for AAAD. This study included 380 patients with AAAD. The clinical features that are associated with PAO were selected using the LASSO regression analysis. Six different machine learning algorithms were tried for modeling, and the performance of each model was analyzed comprehensively using receiver operating characteristic curves, calibration curve, precision recall curve, and decision analysis curves. Explain the optimal model through Shapley Additive Explanation (SHAP) and perform an individualized risk assessment. After comprehensive analysis, the authors believe that the extreme gradient boosting (XGBoost) model is the optimal model, with better performance than other models. The authors successfully built a prediction model for PAO in AAAD patients based on the XGBoost algorithm and interpreted the model with the SHAP method, which helps to identify high-risk AAAD patients at an early stage and to adjust individual patient-related clinical treatment plans in a timely manner.

Cognitive Effects of Body Temperature During Hypothermic Circulatory Arrest Trial (GOT ICE): A Randomized Clinical Trial Comparing Outcomes After Aortic Arch Surgery

BACKGROUND

Deep hypothermia has been the standard for hypothermic circulatory arrest (HCA) during aortic arch surgery. However, centers worldwide have shifted toward lesser hypothermia with antegrade cerebral perfusion. This has been supported by retrospective data, but there has yet to be a multicenter, prospective randomized study comparing deep versus moderate hypothermia during HCA.

METHODS

This was a randomized single-blind trial (GOT ICE [Cognitive Effects of Body Temperature During Hypothermic Circulatory Arrest]) of patients undergoing arch surgery with HCA plus antegrade cerebral perfusion at 4 US referral aortic centers (August 2016-December 2021). Patients were randomized to 1 of 3 hypothermia groups: DP, deep (≤20.0 °C); LM, low-moderate (20.1-24.0 °C); and HM, high-moderate (24.1-28.0 °C). The primary outcome was composite global cognitive change score between baseline and 4 weeks postoperatively. Analysis followed the intention-to-treat principle to evaluate if: (1) LM noninferior to DP on global cognitive change score; (2) DP superior to HM. The secondary outcomes were domain-specific cognitive change scores, neuroimaging findings, quality of life, and adverse events.

RESULTS

A total of 308 patients consented; 282 met inclusion and were randomized. A total of 273 completed surgery, and 251 completed the 4-week follow-up (DP, 85 [34%]; LM, 80 [34%]; HM, 86 [34%]). Mean global cognitive change score from baseline to 4 weeks in the LM group was noninferior to the DP group; likewise, no significant difference was observed between DP and HM. Noninferiority of LM versus DP, and lack of difference between DP and HM, remained for domain-specific cognitive change scores, except structured verbal memory, with noninferiority of LM versus DP not established and structured verbal memory better preserved in DP versus HM (P = 0.036). There were no significant differences in structural or functional magnetic resonance imaging brain imaging between groups postoperatively. Regardless of temperature, patients who underwent HCA demonstrated significant reductions in cerebral gray matter volume, cortical thickness, and regional brain functional connectivity. Thirty-day in-hospital mortality, major morbidity, and quality of life were not different between groups.

CONCLUSIONS

This randomized multicenter study evaluating arch surgery HCA temperature strategies found low-moderate hypothermia noninferior to traditional deep hypothermia on global cognitive change 4 weeks after surgery, although in secondary analysis, structured verbal memory was better preserved in the deep group. The verbal memory differences in the low- and high-moderate groups and structural and functional connectivity reductions from baseline merit further investigation and suggest opportunities to further optimize brain perfusion during HCA.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02834065.

Metabolic Syndrome and Its Components are Associated with In-Hospital Complications after Thoracic Endovascular Aortic Repair for Acute Type B Aortic Dissection

BACKGROUND

This study aimed to explore whether and to what extent metabolic syndrome (MetS) and its components are associated with in-hospital complications in patients with acute type B aortic dissection after thoracic endovascular aortic repair (TEVAR).

METHODS

We retrospectively enrolled 684 patients who had undergone TEVAR. Demographic and clinical data were collected and subgroup analysis, mixed-model regression analysis, scoring systems, and receiver operating characteristic (ROC) curve analyses were performed.

RESULTS

Overall, 684 inpatients were assigned to the poor outcome (n = 90) or no complications (n = 594) group. Compared to the no complications group, the poor outcome group had a higher incidence of MetS (44 [48.9%] vs. 120 [20.2%], P < 0.05). In the subgroup analysis, in-hospital complications were present in 3.1%, 6.6%, 11.9%, 20.7%, 40.0%, and 62.5% of patients in the 6 groups who met the 0, 1, 2, 3, 4, and 5 MetS diagnostic criteria, respectively. On multivariable logistic regression, hypertension (odds ratio [OR]: 2.680; 95% confidence interval [CI]: 1.571-4.570), type 2 diabetes (OR: 2.135; 95% CI: 1.192-3.824), quartiles of body mass index (OR: 1.801; 95% CI: 1.415-2.291), high-density lipoprotein cholesterol (OR: 0.763; 95% CI: 0.611-0.953), and systolic blood pressure (OR: 1.894; 95% CI: 1.486-2.413) were independent factors for in-hospital complications after adjustment for other risk factors. After adjusting for potential confounding factors, MetS was an independent risk factor for in-hospital complications. We established a scoring system for each component and the area under the ROC curve was 0.664 (95% CI: 0.618-0.710) in all patients, 0.672 (95% CI: 0.595-0.749) in patients with MetS, and 0.610 (95% CI: 0.552-0.667) in patients without MetS, as determined by ROC analysis.

CONCLUSIONS

MetS, especially the blood pressure component, confers a greater risk of in-hospital complications in patients with acute type B aortic dissection after TEVAR.

Current Surgical Management of Acute Type A Aortic Dissection in China: A Multicenter Registry Study

Background

Many countries and regions have established multicenter registration studies to improve the outcomes of acute type A aortic dissection (ATAAD).

Objectives

The aims of this study were to report actual preoperative management, surgery type, and early outcomes of surgical treatment for ATAAD in China.

Methods

This cohort study uses data from the China Registry of Type A Aortic Dissection, a national clinical registry to investigate management of patients with Stanford type A aortic dissection. The data, including surgical management and outcomes of patients with ATAAD, were analyzed from January 2018 to December 2021.

Results

A total of 1,058 patients with ATAAD were enrolled in this study between January 2018 and December 2021. The mean age of all patients was 51.6 ±11.7 years. The median interval from onset to hospital was 10.65 hours (IQR: 6-24 hours), and the median interval from entering the emergency room to starting operation was 13 hours (IQR: 4.08-28.7 hours). Total arch repair was performed in 938 patients (88.7%), and frozen elephant trunk repair was performed in 800 patients (75.6%). The incidence of early mortality was 7.6%.

Conclusions

The population of patients with ATAAD in China experienced a longer interval from onset to arrival at the hospital, received more extensive aortic arch repair, and showed a relatively lower early mortality. These findings suggest that there may be a huge survivor bias in patients with ATAAD in China, more efforts should be made to promote prehospital emergency care and preoperative management of Chinese ATAAD patients. (A multicenter registration study of aortic dissection in China; ChiCTR1800015338).

Comprehensive review of hybrid aortic arch repair with focus on zone 0 TEVAR and our institutional experience

Even with increasing operator experience and a better understanding of the disease and the operation, intervention for aortic arch pathologies continues to struggle with relatively higher mortality, reintervention, and neurologic complications. The hybrid aortic arch repair was introduced to simplify the procedure and improve the outcome. With recent industry-driven advances, hybrid repairs are not only offered to poor surgical candidates but have become mainstream. This review discusses the evolution of hybrid repair, terminology pertinent to this technique, and results. In addition, we aim to provide a pervasive review of hybrid aortic arch repairs with reference to relevant literature for a detailed understanding. We have also discussed our institutional experience with hybrid repairs.

Aortic arch repair: lessons learned over three decades at Baylor College of Medicine

The treatment of complex aortic arch disease continues to be among the most demanding cardiovascular operations, with a considerable risk of death and stroke. Since January 1990, our single-practice service has performed over 3000 repairs of the aortic arch. Our aim was to describe the progression of our technical approach to open aortic arch repair. Our center's surgical technique has evolved considerably over the last three decades. When it comes to initial arterial cannulation, we have shifted away from femoral artery cannulation to innominate and axillary artery cannulation. During difficult repairs, this transition has made it easier to use antegrade cerebral perfusion rather than retrograde cerebral perfusion, which was commonly used in the early days. Brain protection tactics during open aortic arch procedures have evolved from profound (≤14 °C) hypothermia during circulatory arrest to moderate (22-24 °C) hypothermia. Aortic arch repair is performed through a median sternotomy and may treat acute aortic dissection, chronic aortic dissection, or degenerative aneurysm. Reoperative repair - that necessitating redo sternotomy - is common in patients undergoing aortic arch repair. The majority of repairs will include varying portions of the ascending aorta and may involve the aortic valve or the aortic root. In some patients, repair may extend into the proximal descending thoracic aorta; this includes elephant trunk, frozen elephant trunk, and antegrade hybrid approaches.

Significant Prediction of In-hospital Major Adverse Events by D-Dimer Level in Patients With Acute Type A Aortic Dissection

Background

Acute type A aortic dissection (ATAAD) is a rare, life-threatening condition affecting the aorta. This study explores the relationship between the level of admission D-dimer, which was assessed during the first 2 h from admission, and in-hospital major adverse events (MAE) with ATAAD.

Methods

A total of 470 patients with enhanced computed tomography (CT) confirmed diagnosis of ATAAD who underwent operation treatment in Guangdong Provincial People's hospital between September 2017 and June 2021 were enrolled in the present study. The X-tile program was used to determine the optimal D-dimer thresholds for risk. Restricted cubic spline (RSC) was performed to assess the association between D-dimer and endpoint. The perioperative data were compared between the two groups, univariate and multivariate analyses were used to investigate the risk factors of major adverse events (in-hospital mortality, gastrointestinal bleeding, paraplegia, acute kidney failure, reopen the chest, low cardiac output syndrome, cerebrovascular accident, respiratory insufficiency, MODS, gastrointestinal bleeding, and severe infection).

Results

Among 470 patients, 151 (32.1%) had MAE. In-hospital mortality was 7.44%. The patients with D-dimer >14,500 ng/ml were more likely to present with acute kidney failure, low cardiac output, cerebrovascular accident, multiple organ dysfunction syndromes (MODS), gastrointestinal bleeding, and severe infection. D-dimer level was an independent risk factor for acute kidney failure (OR 2.09, 95% CI: 1.25–3.51, p = 0.005), MODS (OR 6.40, 95% CI: 1.23–33.39, p = 0.028), gastrointestinal bleeding (OR 17.76, 95% CI: 1.99–158.78, p = 0.010) and mortality (OR 3.17, 95% CI: 1.32–7.63, p = 0.010). Multivariate regression analysis of adverse events also suggested that D-dimer >14,500 ng/ml (OR 1.68, 95% CI: 1.09–2.61, p = 0.020) was the independent risk factor of major adverse events.

Conclusions

Increasing D-dimer levels were independently associated with the in-hospital MAE and thus can be used as a useful prognostic biomarker before the surgery.

Parallel grafts and physician modified endografts for endovascular repair of the aortic arch

Aortic arch aneurysms are a challenging clinical problem especially in high-risk patients. Open aortic arch replacement, even in the best of centers, carries significant risk of stroke or death in this high-risk population. Many high-risk patients are deemed inoperable and not offered repair. Branched and fenestrated thoracic endografts are currently undergoing clinical trials in the United States but are not yet commercially available. Many elderly and frail patients have significant brachiocephalic occlusive disease or anatomy excluding them for consideration for such clinical trials. These patients also present with acute aortic syndromes requiring urgent or emergent repair and are unable to participate in clinical trials due to the time required to have such devices available. Alternative endovascular therapies, including parallel stent grafts (including Chimneys, Snorkels and Periscopes) and physician modified thoracic endografts, have been used to treat such high-risk patients combined with commercially available thoracic endovascular aneurysm repair (TEVAR) devices. This paper aims to review the techniques and current reported outcomes from parallel stent grafts and physician modified devices used to treat high risk patients undergoing repair for aortic arch pathologies.

Postoperative Hepatic Dysfunction After Frozen Elephant Trunk for Type A Aortic Dissection

Background: This study was aimed to investigate the incidence, risk factors, and outcomes of patients with postoperative hepatic dysfunction (PHD) after frozen elephant trunk (FET) for type A aortic dissection (TAAD).

Method: A retrospective study was performed with 492 patients who underwent FET for TAAD between 2015 and 2019. Independent risk factors for PHD were determined by multivariate mixed-effect logistic analysis with surgeon-specific factor as a random effect.

Results: The incidence of PHD was 25.4% (n = 125) in our cohort. Patients with PHD presented higher early mortality (10.4 vs. 1.1%, p < 0.001), rates of acute kidney injury (42.4 vs. 12.8%, p < 0.001), and newly required dialysis (23.2 vs. 3.0%, p < 0.001) compared with those without PHD. Moreover, with the median follow-up period of 41.3 months, the survival curve was worse in patients with PHD compared with no PHD group (log-rank p < 0.001), whereas it was similar after excluding patients who died within 30 days (log-rank p = 0.761). Multivariable analyses suggested that PHD was predicted by preoperative aspartate transferase [odds ratio (OR), 1.057; 95% confidence intervals (CI), 1.036–1.079; p < 0.001], celiac trunk malperfusion (OR, 3.121; 95% CI, 1.008–9.662; p = 0.048), and cardiopulmonary bypass time (OR, 1.014; 95% CI, 1.005–1.023; p = 0.003). Retrograde perfusion (OR, 0.474; 95% CI, 0.268–0.837; p = 0.010) was associated with a reduced risk of PHD. Celiac trunk malperfusion was an independent predictor for PHD but not associated with early mortality and midterm survival.

Conclusions: PHD was associated with increased early mortality and morbidity, but not with late death in midterm survival. PHD was predicted by preoperative aspartate transferase, celiac trunk malperfusion, and cardiopulmonary bypass (CPB) time, and retrograde perfusion was associated with a reduced risk of PHD.

Association of Apoptosis-Mediated CD4+ T Lymphopenia With Poor Outcome After Type A Aortic Dissection Surgery

Background: Many patients with type A aortic dissection (AAD) show low lymphocyte counts pre-operatively. The present study investigated the prognostic values of lymphopenia and lymphocyte subsets for the postoperative major adverse events (MAEs) in AAD patients undergoing surgery, and explore mechanisms of lymphopenia.

Methods: We retrospectively analyzed pre-operative lymphocyte counts in 295 AAD patients treated at two hospitals, and evaluated their correlation with MAEs. We prospectively recruited 40 AAD patients and 20 sex- and age-matched healthy donors (HDs), and evaluated lymphocyte subsets, apoptosis, and pyroptosis by flow cytometry.

Results: Multivariable regression analysis of the retrospective cohort revealed pre-operative lymphopenia as a strong predictor of MAEs (odds ratio, 4.152; 95% CI, 2.434–7.081; p < 0.001). In the prospective cohort, lymphocyte depletion in the AAD group was mainly due to loss of CD4⁺ and CD8⁺ T cells as compared with HDs (CD4⁺ T cells: 346.7 ± 183.6 vs. 659.0 ± 214.6 cells/μl, p < 0.0001; CD8⁺ T cells: 219.5 ± 178.4 vs. 354.4 ± 121.8 cells/μl, p = 0.0036). The apoptosis rates of CD4⁺ and CD8⁺ T cells were significantly higher in AAD patients relative to HDs (both p < 0.0001). Furthermore, the pre-operative CD4⁺ T cells count at a cut-off value of 357.96 cells/μl was an effective and reliable predictor of MAEs (area under ROC curve = 0.817; 95% CI, 0.684-0.950; sensitivity, 74%; specificity, 81%; p < 0.005). Pre-operative lymphopenia, mainly due to CD4⁺ T cells exhaustion by apoptosis, correlates with poor prognosis in AAD patients undergoing surgery.

Conclusion: Pre-operative lymphopenia in particular CD4⁺ T lymphopenia via apoptosis correlates with poor prognosis in AAD patients undergoing surgery.

New-Onset Postoperative Atrial Fibrillation After Total Arch Repair Is Associated With Increased In-Hospital Mortality

Background

It is well established that postoperative atrial fibrillation (POAF) is associated with adverse postoperative outcomes after major cardiac operations. The purpose of this study was to investigate the incidence of new‐onset POAF after successful total arch repair surgery and the association between POAF and in‐hospital mortality.

Methods and Results

All consecutive patients undergoing total arch repair from September 2012 to December 2019 in Fuwai hospital were enrolled (n=1280). Patients diagnosed with preoperative atrial fibrillation were excluded. POAF was diagnosed as the new‐onset atrial fibrillation or flutter for more than 5 minutes based on continuous electrocardiogram monitoring. A logistic regression model was used to determine predictors of in‐hospital mortality. Multivariable adjustment, inverse probability of treatment weighting, and propensity score matching were used to adjust for confounders. POAF was diagnosed in 32.3% (411/1271) of this cohort population. The occurrence of new‐onset POAF was associated with age (odds ratio [OR], 1.05; 95% CI, 1.04–1.06; P<0.001), male sex (OR, 0.72; 95% CI, 0.52–0.98; P=0.035), and surgery duration (OR, 1.2; 95% CI, 1.12–1.28; P<0.001). The in‐hospital mortality was significantly higher in patients with POAF than those without POAF (10.7% versus 2.4%, P<0.001). Inverse probability of treatment weighting and propensity score matching analyses confirmed the results. The increased in‐hospital mortality in POAF group still existed among subgroup analysis based on different age, sex, hypertension, smoking, and hypokalemia, combined with cardiac surgery, and deep hypothermic circulatory arrest.

Conclusions

More careful attention should be given to POAF after total arch repair surgery. The incidence of POAF after total arch repair surgery was 32.3% and associated with increased in‐hospital mortality. The elderly female patient who experienced longer operation duration was at highest risk for POAF.

Does deeper hypothermia reduce the risk of acute kidney injury after circulatory arrest for aortic arch surgery?

OBJECTIVES

The impact of hypothermic circulatory arrest (HCA) temperature on postoperative acute kidney injury (AKI) has not been evaluated. This study examined the association between circulatory arrest temperatures and AKI in patients undergoing proximal aortic surgery with HCA.

METHODS

A total of 759 consecutive patients who underwent proximal aortic surgery (ascending ± valve ± root) including arch replacement requiring HCA between July 2005 and December 2016 were identified from a prospectively maintained institutional aortic surgery database. The primary outcome was AKI as defined by Risk, Injury, Failure, Loss, End Stage Renal Disease (ESRD) criteria. The association between minimum nasopharyngeal (NP) and bladder temperatures during HCA and postoperative AKI was assessed, adjusting for patient-level factors using multivariable logistic regression.

RESULTS

A total of 85% (n = 645) of patients underwent deep hypothermia (14.1-20.0°C), 11% (n = 83) low-moderate hypothermia (20.1-24.0°C) and 4% (n = 31) high-moderate hypothermia (24.1-28.0°C) as classified by NP temperature. When analysed by bladder temperature, 59% (n = 447) underwent deep hypothermia, 22% (n = 170) low-moderate, 16% (n = 118) high-moderate and 3% mild (n = 24) (28.1-34.0°C) hypothermia. The median systemic circulatory arrest time was 17 min. The incidence of AKI did not differ between hypothermia groups, whether analysed using minimum NP or bladder temperature. In the multivariable analysis, the association between degree of hypothermia and AKI remained non-significant whether analysed as a categorical variable (hypothermia group) or as a continuous variable (minimum NP or bladder temperature) (all P > 0.05).

CONCLUSIONS

In patients undergoing proximal aortic surgery including arch replacement requiring HCA, degree of systemic hypothermia was not associated with the risk of AKI. These data suggest that moderate hypothermia does not confer increased risk of AKI for patients requiring circulatory arrest, although additional prospective data are needed.

Risk factor analysis of clinical outcomes of total aortic arch replacement and frozen elephant trunk with aortic balloon occlusion

Background

Total aortic arch replacement (TAR) with frozen elephant trunk (FET) requires hypothermic circulatory arrest (HCA) for 20 min, which increases the surgical risk. We invented an aortic balloon occlusion (ABO) technique that requires 5 min of HCA on average to perform TAR with FET and investigated the possible merit of this new method in this study.

Methods

This retrospective study included consecutive patients who underwent TAR and FET (consisting of 130 cases of ABO group and 230 cases of conventional group) in Fuwai Hospital between August 2017 and February 2019. In addition to the postoperative complications, the alterations of blood routine tests, alanine transaminase (ALT) and aspartate transaminase (AST) during in-hospital stay were also recorded.

Results

The 30-day mortality rates were similar between ABO group (4.6%) and conventional group (7.8%, P = 0.241). Multivariate analysis showed ABO reduced postoperative acute kidney injury (23.1% vs. 35.7%, P = 0.013) and hepatic injury (12.3% vs. 27.8%, P = 0.001), and maintained similar cost to patients (25.5 vs. 24.9 kUSD, P = 0.298). We also found that AST was high during intensive care unit (ICU) stay and recovered to normal before discharge, while ALT was not as high as AST in ICU but showed a rising tendency before discharge. The platelet count showed a rising tendency on postoperative day 3 and may exceed the preoperative value before discharge.

Conclusions

The ABO achieved the surgical goal of TAR with FET with an improved recovery process during the in-hospital stay.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13019-021-01643-3.

Improvement of Clinical Outcomes of Total Aortic Arch Replacement and Frozen Elephant Trunk Surgery With Aortic Balloon Occlusion

Background: Total aortic arch replacement (TAR) with frozen elephant trunk (FET) surgery provides improved long-term results, but the surgery itself is associated with higher risks compared with isolated proximal reconstructions. We applied an aortic balloon occlusion (ABO) technique to reduce the circulatory arrest (CA) time and improve other clinical outcomes. Methods: All patients who underwent TAR with FET surgery (130 with ABO technique, 230 with the conventional approach) in Fuwai Hospital from August 2017 to February 2019 were reviewed in this retrospective observational cohort study. Intra- and early-postoperative results and clinical characteristics were analyzed. Results: After 1:1 propensity score matching (130 cases in each group), the 30-day mortality of the ABO group and the conventional group were 4.6% and 10.8% (p = 0.063), respectively. Although the reduction in complications was not statistically significant, the complication rate in the ABO group was relatively low, having fewer cases of postoperative renal (23.1 vs. 38.5%, p = 0.007) and hepatic (12.3 vs. 30.0%, p < 0.001) injury, lower postoperative wake-up time (15.2 ± 23.6 h vs. 20.1 ± 26.5 h, respectively, p < 0.001), reduced chest tube output (176.03 ± 143.73 ml vs. 213.29 ± 130.12 ml, respectively, p = 0.003), lower red blood cell transfusion volume (4.98 ± 6.53 u vs. 7.28 ± 10.41 u, respectively, p = 0.008), and no fatal events. Conclusions: The ABO technique is a simple method that can reduce the CA time and improve the recovery stage following TAR with FET surgery. The technique represents a practical strategy to treat patients with high operative risks due to its lower complication rate compared with the conventional approach.

Hybrid repair versus conventional open repair for aortic arch dissection

BACKGROUND

A dissection of the aorta is a separation or tear of the intima from the media. This tear allows blood to flow not only through the original aortic flow channel (known as the true lumen), but also through a second channel between the intima and media (known as the false lumen). Aortic dissection is a life-threatening condition which can be rapidly fatal. There is debate on the optimal surgical approach for aortic arch dissection. People with ascending aortic dissection have poor rates of survival. Currently open surgical repair is regarded as the standard treatment for aortic arch dissection. We intend to review the role of hybrid and open repair in aortic arch dissection.

OBJECTIVES

To assess the effectiveness and safety of a hybrid technique of treatment over conventional open repair in the management of aortic arch dissection.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL and AMED databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 8 February 2021. We also undertook reference checking for additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and clinical controlled trials (CCTs), which compared the effects of hybrid repair techniques versus open surgical repair of aortic arch dissection. Outcomes of interest were dissection-related mortality and all-cause mortality, neurological deficit, cardiac injury, respiratory compromise, renal ischaemia, false lumen thrombosis (defined by partial or complete thrombosis) and mesenteric ischaemia.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all records identified by the literature searches to identify those that met our inclusion criteria. We planned to undertake data collection and analysis in accordance with recommendations described in the Cochrane Handbook for Systematic Reviews of Interventions. We planned to assess the certainty of the evidence using GRADE.

MAIN RESULTS

We identified one ongoing study and two unpublished studies that met the inclusion criteria for the review. Due to a lack of study data, we could not compare the outcomes of hybrid repair to conventional open repair for aortic arch dissection.

AUTHORS' CONCLUSIONS

This review revealed one ongoing RCT and two unpublished RCTs evaluating hybrid versus conventional open repair for aortic arch surgery. Observational data suggest that hybrid repair for aortic arch dissection could potentially be favourable, but conclusions can not be drawn from these studies, which are highly selective, and are based on the clinical status of the patient, the presence of comorbidities and the skills of the operators. However, a conclusion about its definitive benefit over conventional open surgical repair cannot be made from this review without published RCTs or CCTs. Future RCTs or CCTs need to have adequate sample sizes and follow-up, and assess clinically-relevant outcomes, in order to determine the optimal treatment for people with aortic arch dissection. It must be noted that this may not be feasible, due to the reasons mentioned.

Early-to-midterm outcomes of aortic balloon occlusion technique versus hybrid procedure for aortic arch diseases

OBJECTIVES

The goal of this study was to compare the early-to-midterm outcomes of patients treated with the frozen elephant trunk procedure with aortic balloon occlusion (FET-ABO) versus hybrid repair for aortic arch diseases.

METHODS

Patients who underwent the FET-ABO (n = 134) and the hybrid procedure (n = 220) from 2017 to 2020 at our institution were analysed retrospectively. Early-to-midterm outcomes were compared using inverse probability weighting. Low-risk and high-risk subgroup analyses were performed according to the cut-off of the additive European System for Cardiac Operative Evaluation value of 6.

RESULTS

The present study demonstrated similar 30-day mortality (3.7% vs 8.6%; P = 0.118) and adverse events between the FET-ABO and the hybrid groups. Fewer intraoperative red blood cell transfusions (0.54 ± 1.45 vs 1.26 ± 2.47 U; P = 0.001), decreased total hospital costs (P < 0.001) and considerable early-to-midterm survival [crude: hazard ratio (HR) 0.40, 95% confidence interval (CI) 0.17-0.91; P = 0.030; adjusted: HR 0.35, 95% CI 0.13-0.91; P = 0.032) were obtained with the FET-ABO compared to the hybrid procedure. The inverse probability weighting method substantiated the foregoing results. Adjusted subgroup analyses suggested that the FET-ABO procedure had a trend towards improved survival in low-risk patients (HR 0.17, 95% CI 0.03-0.93; P = 0.041) and achieved outcomes comparable to those of the hybrid procedure in high-risk patients (HR 0.46, 95% CI 0.15-1.42; P = 0.176).

CONCLUSIONS

The FET-ABO technique could be better promoted in hospitals lacking experience and equipment and could be more viable and cost-effective for selected patients compared with the hybrid procedure.

Hybrid repair versus conventional open repair for thoracic aortic arch aneurysms

BACKGROUND

Thoracic aortic arch aneurysms (TAAs) can be a life-threatening condition due to the potential risk of rupture. Treatment is recommended when the risk of rupture is greater than the risk of surgical complications. Depending on the cause, size and growth rate of the TAA, treatment may vary from close observation to emergency surgery. Aneurysms of the thoracic aorta can be managed by a number of surgical techniques. Open surgical repair (OSR) of aneurysms involves either partial or total replacement of the aorta, which is dependent on the extent of the diseased segment of the aorta. During OSR, the aneurysm is replaced with a synthetic graft. Hybrid repair (HR) involves a combination of open surgery with endovascular aortic stent graft placement. Hybrid repair requires varying degrees of invasiveness, depending on the number of supra-aortic branches that require debranching. The hybrid technique that combines supra-aortic vascular debranching with stent grafting of the aortic arch has been introduced as a therapeutic alternative. However, the short- and long-term outcomes of HR remain unclear, due to technical difficulties and complications as a result of the angulation of the aortic arch as well as handling of the arch during surgery.

OBJECTIVES

To assess the effectiveness and safety of HR versus conventional OSR for the treatment of TAAs.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL and AMED databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 22 March 2021. We also searched references of relevant articles retrieved from the electronic search for additional citations.

SELECTION CRITERIA

We considered for inclusion in the review all published and unpublished randomised controlled trials (RCTs) and controlled clinical trials (CCTs) comparing HR to OSR for TAAs.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all titles and abstracts obtained from the literature search to identify those that met the inclusion criteria. We retrieved the full text of studies deemed as potentially relevant by at least one review author. The same review authors screened the full-text articles independently for inclusion or exclusion.

MAIN RESULTS

No RCTs or CCTs met the inclusion criteria for this review.

AUTHORS' CONCLUSIONS

Due to the lack of RCTs or CCTs, we were unable to determine the safety and effectiveness of HR compared to OSR in people with TAAs, and we are unable to provide high-certainty evidence on the optimal surgical intervention for this cohort of patients. High-quality RCTs or CCTs are necessary, addressing the objective of this review.

Association of body mass index with in-hospital major adverse outcomes in acute type A aortic dissection patients in Fujian Province, China: a retrospective study

Background

Abnormal body mass index (BMI) has been related to a higher risk of adverse outcomes in patients undergoing cardiac surgery. However, the effects of BMI in patients with acute type A aortic dissection (AAAD) on postoperative outcomes remain unclear. This study aimed to explore the relationships between BMI and in-hospital major adverse outcomes (MAO) in AAAD patients.

Methods

Patients who underwent AAAD surgery at Cardiac Medical Center of Fujian Province from June 2013 to March 2020 were retrospectively evaluated. They were divided into three groups on the basis of Chinese BMI classification established by the World Health Organization: normal weight group (BMI 18.5–23.9 kg/m²), overweight group (BMI 24–27.9 kg/m²), and obese group (BMI >28 kg/m²). Patients’ baseline characteristics, preoperative, operative, and postoperative data were collected. A multivariable logistic regression analysis model was performed to identify the association between BMI and MAO in AAAD patients.

Results

Of 777 cases, 31.9% were normal weight, 52.5% were overweight, and 15.6% were obese. A total of 160(20.6%) patients died in-hospital. There was a significant difference between the three groups for MAO (62.9% vs 72.1% vs 77.7%, respectively, P = 0.006). The incidence of postoperative complications did not differ among the three groups, except for postoperative bleeding, and prolonged mechanical ventilation, the proportion of which were higher in the overweight and obese groups. Besides, multivariable logistic regression analysis demonstrated that a higher risk of MAO in the overweight [odds ratios (ORs):1.475, 95%CI:1.006–2.162], and obese patients (ORs:2.147, 95%CI:1.219–3.782) with reference to the normal weight patients, and age, white blood cell, prior stroke and cardiopulmonary bypass time were also associated with in-hospital MAO (P<0.05).

Conclusions

BMI is independently associated with higher in-hospital MAO in patients who underwent AAAD surgery.

Aortic arch surgery at 32°C: mild hypothermia and unilateral antegrade cerebral perfusion

OBJECTIVES

With development of antegrade cerebral perfusion, the necessity of deep hypothermic circulatory arrest (CA) in aortic arch surgery has been called into question. To minimize the adverse effects of hypothermia, surgeons now perform these procedures closer to normothermia. This study examined postoperative outcomes of hemiarch replacement patients using unilateral selective antegrade cerebral perfusion and mild hypothermic CA.

METHODS

Single-centre retrospective review of 66 patients undergoing hemiarch replacement with mild hypothermic CA (32°C) and unilateral selective antegrade cerebral perfusion between 2011 and 2018. Antegrade cerebral perfusion was delivered using right axillary artery cannulation. Postoperative data included death, neurological dysfunction, acute kidney injury and renal failure requiring new dialysis. Additional intraoperative metabolic data and blood transfusions were obtained.

RESULTS

Eighty-six percent of patients underwent elective surgery. Mean age was 67 ± 3 years. Lowest mean core body temperature was 32 ± 2°C. Average CA was 17 ± 5 min. No intraoperative or 30-day mortality occurred. Survival was 97% at 1 year, 91% at 3 years and 88% at 5 years. Permanent and temporary neurological dysfunction occurred in 1 (2%) and 2 (3%) patients, respectively. Only 3 (5%) patients suffered postoperative stage 3 acute kidney injury requiring new dialysis. Intraoperative transfusions occurred in 44% of patients and no major metabolic derangements were observed.

CONCLUSIONS

In patients undergoing hemiarch surgery, mild hypothermia (32°C) with unilateral selective antegrade cerebral perfusion via right axillary cannulation is associated with low mortality and morbidity, offering adequate neurological and renal protection. These findings require validation in larger, prospective clinical trials.

Application of Aortic Balloon Occlusion in Total Aortic Arch Replacement with Frozen Elephant Trunk on Clinical Endpoints for Aortic Dissection Patients

Purpose: Total aortic arch replacement (TAR) with frozen elephant trunk (FET) is the standard operation for treating aortic dissection (AD) patients involving aortic arch with high operative risk due to long circulatory arrest (CA). We used aortic balloon occlusion technique that safely reduced the CA time to 5 min in average and investigated whether it can improve the clinical endpoints.

Methods: All patients diagnosed with AD and underwent TAR with FET operation (123 with aortic balloon occlusion and 221 with conventional method) in Fuwai Hospital during August 2017 and February 2019 was reviewed in this retrospective observational study.

Results: After propensity score matching, the 30-day mortality of aortic balloon occlusion group and conventional group was 4.88% and 11.38% (P = 0.062), respectively. In multivariate analysis, aortic balloon occlusion is one of the factors that reduced the risk for renal and hepatic injury, shortened postoperative conscious revival time, and reduced red blood cell (RBC) transfusion during operation.

Conclusions: The aortic balloon occlusion technique, as a perfusion strategy during operation, could alleviate postoperative complication. This method deserves further attention in future clinical practice for its value in treating patients with higher operative risks.

Management of aortic root in type A dissection: Bentall approach

BACKGROUND

We analyzed the results of the modified Bentall procedure in a high-risk group of patients presenting with acute type A aortic dissection (ATAAD).

METHODS

ATAAD patients undergoing a modified Bentall between 1996 and 2018 (n = 314) were analyzed. Mechanical composite conduits were used in 45%, and biological ones using either a bioprosthesis implanted into an aortic graft (33%) or xeno-/homograft root conduits (22%) in the rest. Preoperative malperfusion was present in 34% of patients and cardiopulmonary resuscitation required in 9%.

RESULTS

Concomitant arch procedures consisted of hemiarch in 56% and total arch/elephant trunk in 34%, while concomitant coronary artery surgery was required in 20%. The average cross-clamp and cardiopulmonary bypass times were 126 ± 43 and 210 ± 76 min, respectively, while the average circulatory arrest times were 29 ± 17 min. A total of 69 patients (22%) suffered permanent neurologic deficit, while myocardial infarction occurred in 18 cases (6%) and low cardiac output syndrome in 47 (15%). The in-hospital mortality rate was 17% due to intractable low cardiac output syndrome (n = 29), major brain injury (n = 16), multiorgan failure (n = 6), and sepsis (n = 2). The independent predictors of in-hospital mortality were critical preoperative state (odds ratio [OR], 5.6; p < .001), coronary malperfusion (OR, 3.6; p = .002), coronary artery disease (OR, 2.6; p = .033), and prior cerebrovascular accident (OR, 5.6; p = .002).

CONCLUSIONS

The modified Bentall operation, along with necessary concomitant procedures, can be performed with good early results in high-risk ATAAD patients presenting.

The anaesthetic management of patients with thoracic ascending aortic aneurysms: A review

Thoracic aortic aneurysms present significant challenges to clinicians, especially due to their complex nature and an evolving understanding of the safest and most effective ways to manage this condition in the perioperative setting. Thoracic aortic aneurysms have a prevalence rate of 1.3-8.9% in men and 1.0-2.2% in women, and they are estimated to affect more than five per 100,000 person-years. This is notable because the complications of thoracic aortic aneurysms can be catastrophic. The current understanding of the optimal intraoperative management of thoracic aortic aneurysms is changing, as more evidence becomes available regarding lung protective ventilation and its role in enhancing patient safety and wellbeing. This review strives to provide a brief historical understanding of thoracic aortic aneurysms and highlight some of the key discoveries and advances in the management of this condition. This review then describes an overview of the general anaesthetic principles associated with thoracic aortic aneurysms, including ventilatory modalities and how these impact a patient's physiology and intraoperative haemodynamics. A brief discussion on one-lung ventilation is then provided, drawing from current literature in the field, to describe the most up-to-date management of thoracic aortic aneurysms.

The strategy of cardiopulmonary bypass for total aortic arch replacement and the frozen elephant trunk technique with aortic balloon occlusion

Objective

To investigate the use of the aortic balloon occlusion technique to assist total aortic arch replacement (TAR) with frozen elephant trunk (FET) to shorten the lower body circulatory arrest (CA) time and raise the nadir temperature during cardiopulmonary bypass.

Methods

This retrospective study reviewed consecutive patients that underwent aortic balloon occlusion to assist TAR with FET and patients that received conventional TAR with FET procedures. Preoperative characteristics, perioperative characteristics and postoperative outcomes were compared between the two groups.

Results

The study included130 patients treated with aortic balloon occlusion and 230 patients treated with conventional TAR with FET. The 30-day mortality rate was similar between the aortic balloon occlusion and conventional groups (4.62% versus 7.83%, respectively). Multivariate analysis showed that aortic balloon occlusion reduced the incidence of acute kidney injury, hepatic injury and red blood cell transfusion. The application of aortic balloon occlusion reduced the mean ± SD CA time from 17.24 ± 4.36 min to 6.33 ± 5.74 min, with the target nadir nasal temperature being increased from 25°C to 28°C.

Conclusion

The aortic balloon occlusion technique achieved significant improvements in reducing complications, but this did not translate into lower 30-day mortality.

Early outcome of aortic balloon occlusion during total aortic arch replacement with the frozen elephant trunk technique for aortic dissection

OBJECTIVES

The aim of this study was to propose and evaluate the new operative technique of aortic balloon occlusion in total aortic arch replacement (TAR) with the frozen elephant trunk that can significantly decrease the time of circulatory arrest and increase the hypothermic cardiopulmonary bypass (CPB) temperature.

METHODS

Between 2010 and 2018, 1335 patients with aortic dissection who underwent TAR with the frozen elephant trunk were included in the study. The newest 80 cases were treated with aortic balloon occlusion. To illustrate the difference with the new procedure, 1255 conventional TAR cases served as the historical control. Femoral and right axillary artery cannulations were used for CPB and antegrade selective cerebral perfusion. Circulatory arrest was implemented at the nasopharyngeal temperature of 28°C with continuous antegrade selective cerebral perfusion. After the stent graft was inserted into the true lumen of the descending aorta, the aortic balloon in a sheath was deployed into the stent graft and positioned at the metal part of the stent graft. When the balloon was inflated with enough saline to compress the stent graft, the sheath was simultaneously pressed by hand to properly fix the balloon and avoid displacement. Then femoral perfusion could be resumed.

RESULTS

The aortic balloon occlusion technique was successful in all patients, with the median duration of circulatory arrest being 5 (interquartile range 3-7) min. The 30-day mortality rate was 6.25% (5/80), whereas with the conventional method it was 9.40% (118/1255). The postoperative conscious revival (8.67 vs 11.40 h, P < 0.001) and mechanical ventilation times (19.70 vs 24.45 h, P = 0.02) were significantly shorter. Decreases in postoperative acute kidney injuries (13.75% vs 32.11%, P = 0.001) and liver injuries (8.75% vs 37.61%, P < 0.001) were also observed. The patients were transfused with lesser quantities of red blood cells, plasma and platelets.

CONCLUSIONS

The aortic balloon occlusion technique is a feasible way to shorten circulatory arrest significantly, to obviate the need for deep hypothermia in TAR with the frozen elephant trunk and to provide favourable protective effects on the central nervous, haematological and visceral systems. With these satisfactory results, this technique deserves further investigation.

In-hospital major adverse outcomes of acute Type A aortic dissection

OBJECTIVES

Acute Type A aortic dissection exhibits poor in-hospital outcomes after emergency surgery. Evaluation of risk predictors for in-hospital major adverse outcomes (MAO) is key to reducing the mortality rate and improving the quality of care.

METHODS

We enrolled 70 patients who presented with postoperative MAO and 195 patients who recovered well. Through univariate and multivariate analyses, clinical characteristics were compared between the patients in the 2 groups.

RESULTS

In-hospital mortality was 6.4% in this series. The patients in the MAO group were older and had a higher frequency of coronary artery involvement by dissection (60.0% vs 21.0%) (P < 0.05). Preoperatively, when compared to the group of patients without MAO, the patients in the MAO group were more likely to have a neurological deficit (18.6% vs 9.7%) and, to a certain extent, lower limb symptoms encompassing visceral and renal malperfusion (20.0% vs 8.2%) (P < 0.05). Compared to patients with MAO, patients without MAO experienced longer duration from initial onset of symptoms to surgery and had an ascending aorta with a larger diameter. In patients with MAO, the average durations of cardiopulmonary bypass (CPB), cardiac arrest and hypothermic circulatory arrest were much longer than those in patients with no MAO (all P < 0.001). Multivariate analysis showed that in-hospital adverse outcomes were associated with older age [odds ratio (OR) = 1.047 (1.008-1.087), P < 0.05], presentation of lower limb symptoms prior to surgery [OR = 2.905 (1.109-7.608), P < 0.05] and long CPB duration [OR = 1.011 (1.005-1.018), P < 0.01]. When patients with acute Type A aortic dissection experienced a duration from symptom onset to surgery [OR = 0.993 (0.987-0.999), P < 0.05] or had an ascending aorta with a large diameter [OR = 0.942 (0.892-0.995), P < 0.05], the number of postoperative adverse events decreased significantly.

CONCLUSIONS

At a centre that has a large caseload, where practitioners can become proficient through experience as well as training, good outcomes can be dependably produced in patients with acute Type A aortic dissection and without malperfusion syndromes. For patients presenting with these risk features, MAO need to be anticipated, and the incidence of a composite end point of major adverse events remains unsatisfactory.

Aortic balloon occlusion technique versus moderate hypothermic circulatory arrest with antegrade cerebral perfusion in total arch replacement and frozen elephant trunk for acute type A aortic dissection

BACKGROUND

Moderate hypothermic circulatory arrest (MHCA) with antegrade cerebral perfusion (ACP) is safe and efficient in total arch replacement (TAR) and frozen elephant trunk (FET) for acute type A aortic dissection (ATAAD). Complications related to hypothermia and ischemia are inevitable, however. The aortic balloon occlusion (ABO) technique is performed to elevate the lowest nasopharyngeal temperature to 28°C and shorten the circulatory arrest time. In this study, we aimed to evaluate the efficacy of this new technique.

METHODS

We reviewed the clinical data of patients with ATAAD who underwent TAR and FET, including 79 who underwent ABO and 109 who underwent MHCA/ACP.

RESULTS

Circulatory arrest time was significantly lower in the ABO group compared with the MHCA/ACP group (mean, 4.8 ± 1.2 minutes vs 18.4 ± 3.1 minutes; P < .001). The composite endpoint was comparable in the 2 groups (11.4% for ABO vs 13.8% for MHCA/ACP; P = .631). Fewer patients in the ABO group developed high-grade acute kidney injury (AKI) according to a modified RIFLE criterion (22.8% vs 36.7%; P = .041), and the rate of hepatic dysfunction was lower in the ABO group (11.4% vs 28.4%; P = .005). Multivariable logistic analysis showed that the ABO technique is protective against duration of ventilation >24 hours (odds ratio [OR], 0.455; 95% confidence interval [CI], 0.234-0.887; P = .021), hepatic dysfunction (OR, 0.218; 95% CI, 0.084-0.561; P = .002), and grade II-III AKI (OR, 0.432; 95% CI, 0.204-0.915; P = .028).

CONCLUSIONS

The ABO technique significantly shortens the circulatory arrest time in TAR and FET. Available clinical data suggest that it has a certain protective effect on the liver and kidney. Future large-sample studies are warranted to thoroughly evaluate this new technique.

Factors Associated with Low Admission Platelet Count in Adults with Acute Aortic Dissection

Purpose: Platelets are crucial components of the coagulation processes, and low admission platelet count (PLC) is associated with adverse clinical outcomes in patients with Stanford type A acute aortic dissection (AAD).

Methods: A total of 130 consecutive patients undergoing Stanford type A AAD surgery in Beijing Anzhen Hospital were enrolled between January 2013 and July 2014. Preoperative clinical and laboratory data from patients were collected. Multiple regression analyses were used to determine the independent factors of low admission platelets.

Results: Adjusted multiple regression analysis showed that age (β: −1.069, 95% confidence interval [CI]: −2.109, −0.029), sex (β: −29.973, 95% CI: −56.512, −3.433), tissue factor pathway inhibitor (TFPI; β: 0.197, 95% CI: 0.039, 0.354), fibrinogen degradation product (FDP) (β: −0.476, 95% CI: −0.879, −0.074), and attack time (β: 11.125, 95% CI: 7.963, 14.287) were significantly associated with admission PLC. Admission PLC increased with attack time up to the 3 days (β: 16.2, 95% CI: 12.1, 20.2).

Conclusions: We found that increasing age, male patients, patients with lower serum levels of TFPI and higher serum levels of FDP, and patients with a shorter attack time were significantly associated with lower PLC at admission. Moreover, the turning point of attack time is 3 days after the onset of dissection.

Pulmonary static inflation with 50% xenon attenuates decline in tissue factor in patients undergoing Stanford type A acute aortic dissection repair

Background

The Stanford type A acute aortic dissection (AAD) carries a high risk of mortality and morbidity, and patients undergoing AAD surgery often bleed excessively and require blood products and transfusions. Thus, we studied how xenon alters coagulation using thromboelastography (TEG) and conventional hemostatic tests for patients with AAD undergoing aortic arch surgery involving cardiopulmonary bypass (CPB)/deep hypothermic circulatory arrest (DHCA).

Methods

This prospective single-center nonrandomized controlled clinical trial, registered in the Chinese Clinical Trial Registry (ChiCTR-ICR-15006435), assessed perioperative clinical variables and serological results from 50 subjects undergoing pulmonary static inflation with 50% nitrogen/50% oxygen from January 2013 to January 2014 and 50 subjects undergoing pulmonary static inflation with 50% xenon/50% oxygen from January 2014 to December 2014 during CPB for Stanford type A AAD. Repeated measures ANOVA were used to identify the effects of xenon on coagulation after surgery. The primary endpoint was perioperative changes in coagulation and fibrinolysis after intubation and 10 minutes, and 6 hours after the operation. The secondary endpoint was to assess the perioperative changes in serum level of tissue factor (TF), tissue factor pathway inhibitor (TFPI) and tissue plasminogen activator (tPA) after intubation and 10 minutes, and 6 hours after the operation.

Results

Mean prothrombin time (PT), activated partial thromboplastin time (APTT), international normalized ratio (INR), median fibrinogen degradation product (FDP), and D-dimer peaked and then decreased over 6 hours after surgery. TEG followed a similar trend. From the start to the end of surgery and until 6 h after surgery, mean TF decreased in controls (β -2.61, P<0.001 and β -2.83, P<0.001, respectively), but was maintained relatively stable in xenon group (β -0.5, P<0.001 and β -0.96, P<0.001, respectively).

Conclusions

Deterioration of coagulation function and activated fibrinolysis was confirmed by conventional tests and TEG analysis after Stanford type A AAD repair. Pulmonary static inflation with 50% xenon attenuates decline in TF in patients undergoing Stanford type A AAD repair.

Abdominal organ protection strategy for aortic arch aneurysm surgery

INTRODUCTION

Body temperature maintained during open distal anastomosis in patients who undergo aortic surgery has been showing an upward trend; however, a higher temperature may increase visceral organ and spinal cord injury. Distal perfusion may reduce abdominal organ injury, especially acute kidney injury (AKI).

METHODS

From 2009 to 2016, 56 patients who underwent ascending aortic and/or aortic arch surgery were enrolled. Open distal anastomosis was performed using one of three protection strategies: 1) systemic temperature of 25°C followed by selective cerebral perfusion (SCP) with lower body circulatory arrest (Group CA25, n=27); 2) systemic temperature of 28°C followed by SCP with lower body circulatory arrest (Group CA28, n=4); and 3) systemic temperature of 28°C followed by SCP with distal aortic perfusion (Group DP, n=25).

RESULTS

During the postoperative course, levels of blood urea nitrogen, creatinine, liver enzymes, lactate dehydrogenase and lactate in Groups CA28 and CA25 were significantly higher than those in Group DP. AKI defined by the AKI Network occurred in 28 cases (50%) and 3 cases required permanent hemodialysis. AKI was significantly higher in Groups CA25 and CA28 than in Group DP (p=0.026). Mid-term follow-up showed that patients who developed postoperative AKI were more likely to suffer from cardiovascular events.

CONCLUSIONS

Distal perfusion during open distal anastomosis reduced kidney and liver injury after thoracic aortic surgery despite an increased body temperature of up to 28°C. This strategy may be useful to prevent AKI, liver dysfunction, the need for hemodialysis and multiple organ failure and could improve mid-term results.

Intraoperative care for aortic surgery using circulatory arrest

The total circulatory arrest (CA) is necessary to achieve optimal surgical conditions in certain aortic pathologies, especially in those affecting the ascending aorta and aortic arch. During this procedure it is necessary to protect all the organs of ischemia, especially those of the central nervous system and for this purpose several strategies have been developed. The first and most important protective method is systemic hypothermia. The degree of hypothermia and the route of application have been evolving and currently tend to use moderate hypothermia (MH) (20.1-28 °C) associated with unilateral or bilateral selective cerebral perfusion methods. In this way the neurological results are better, the interval of security is greater and the times of extracorporeal circulation are smaller. Even so, it is necessary to take into account that there is the possibility of ischemia in the lower part of the body, especially of the abdominal viscera and the spinal cord, therefore the time of circulatory stop should be limited and not to exceed 80 minutes. Evidence of possible neurological drug protection is very weak and only mannitol, magnesium, and statins can produce some benefit. Inhalational anesthetics and some intravenous seem to have advantages, but more studies would be needed to test their long-term benefit. Other important parameters to be monitored during these procedures are blood glucose, anemia and coagulation disorders and acid-base balance. The recommended monitoring is common in complex cardiovascular procedures and it is of special importance the neurological monitoring that can be performed with several techniques, although currently the most used are Bispectral Index (BIS) and Near-Infrared Spectroscopy (NIRS). It is also essential to monitor the temperature routinely at the nasopharyngeal and bladder level and it is important to control coagulation with rotational thromboelastometry (ROTEM).

Unwarranted Variation in the Quality of Care for Patients With Diseases of the Thoracic Aorta

BACKGROUND

Thoracic aortic disease has a high mortality. We sought to establish the contribution of unwarranted variation in care to regional differences in outcomes observed in patients with thoracic aortic disease in England.

METHODS AND RESULTS

Data from the Hospital Episode Statistics (HES) and the National Adult Cardiac Surgery Audit (NACSA) were extracted. A parallel systematic review/meta-analysis through December 2015, and structure and process questionnaire of English cardiac surgery units were also accomplished. Treatment and mortality rates were investigated. A total of 24 548 adult patients in the HES study, 8058 in the NACSA study, and 103 543 from a total of 33 studies in the systematic review were obtained. Treatment rates for thoracic aortic disease within 6 months of index admission ranged from 7.6% to 31.5% between English counties. Risk-adjusted 6-month mortality in untreated patients ranged from 19.4% to 36.3%. Regional variation persisted after adjustment for disease or patient factors. Regional cardiac units with higher case volumes treated more-complex patients and had significantly lower risk-adjusted mortality relative to low-volume units. The results of the systematic review indicated that the delivery of care by multidisciplinary teams in high-volume units resulted in better outcomes. The observational analyses and the online survey indicated that this is not how services are configured in most units in England.

CONCLUSIONS

Changes in the organization of services that address unwarranted variation in the provision of care for patients with thoracic aortic disease in England may result in more-equitable access to treatment and improved outcomes.

Effects of pulmonary static inflation with 50% xenon on oxygen impairment during cardiopulmonary bypass for stanford type A acute aortic dissection: A pilot study

BACKGROUND

The goal of this study was to investigate the effects of pulmonary static inflation with 50% xenon on postoperative oxygen impairment during cardiopulmonary bypass (CPB) for Stanford type A acute aortic dissection (AAD).

METHODS

This prospective single-center nonrandomized controlled clinical trial included 100 adult patients undergoing surgery for Stanford type A AAD at an academic hospital in China. Fifty subjects underwent pulmonary static inflation with 50% oxygen from January 2013 to January 2014, and 50 underwent inflation with 50% xenon from January 2014 to December 2014. During CPB, the lungs were inflated with either 50% xenon (xenon group) or 50% oxygen (control group) to maintain an airway pressure of 5 cm H2O. The primary outcome was oxygenation index (OI) value after intubation, and 10 minutes and 6 hours after the operation. The second outcome was cytokine and reactive oxygen species levels after intubation and 10 minutes, 6 hours, and 24 hours after the operation.

RESULTS

Patients treated with xenon had lower OI levels compared to the control group before surgery (P = 0.002); however, there was no difference in postoperative values between the 2 groups. Following surgery, mean maximal OI values decreased by 18.8% and 33.8%, respectively, in the xenon and control groups. After surgery, the levels of interleukin-6 (IL-6), tumor necrosis factor alpha, and thromboxane B2 decreased by 23.5%, 9.1%, and 30.2%, respectively, in the xenon group, but increased by 10.8%, 26.2%, and 26.4%, respectively, in the control group. Moreover, IL-10 levels increased by 28% in the xenon group and decreased by 7.5% in the control group. There were significant time and treatment-time interaction effects on methane dicarboxylic aldehyde (P = 0.000 and P = 0.050, respectively) and myeloperoxidase (P = 0.000 and P = 0.001 in xenon and control groups, respectively). There was no difference in hospital mortality and 1-year survival rate between the 2 groups.

CONCLUSION

Pulmonary static inflation with 50% xenon during CPB could attenuate OI decreases at the end of surgery for Stanford type A AAD. Thus, xenon may function by triggering anti-inflammatory responses and suppressing pro-inflammatory and oxidative effects.

Mechanism and early intervention research on ALI during emergence surgery of Stanford type-A AAD: Study protocol for a prospective, double-blind, clinical trial

BACKGROUND

Stanford type-A acute aortic dissection (AAD) is a severe cardiovascular disease demonstrating the characteristics of acute onset and rapid development, with high morbidity and mortality. The available evidence shows that preoperative acute lung injury (ALI) induced by Stanford type-A AAD is a frequent and important cause for a number of untoward consequences. However, there is no study assessing the incidence of preoperative ALI and its independent determinants before Standford type-A AAD surgery in Chinese adult patients.

METHODS/DESIGN

This is a prospective, double-blind, signal-center clinical trial. We will recruit 130 adult patients undergoing Stanford type-A AAD surgery. The incidence of preoperative ALI will be evaluated. Perioperative clinical baselines and serum variables including coagulation, fibrinolysis, inflammatory, reactive oxygen species, and endothelial cell function will be assayed. The independent factors affecting the occurrence of preoperative ALI will be identified by multiple logistic regression analysis.

TRIAL REGISTRATION

ClinicalTrials.gov (https://register.clinicaltrials.gov/), Registration number NCT01894334.

Aortic Arch Replacement in Patients With Chronic Dissection: Special Considerations

The progressive expansion of residual, chronic DeBakey type I dissection often necessitates repair of the aortic arch and the distal aorta (ie, descending thoracic and thoracoabdominal aorta). The vast majority of patients with chronic aortic dissection facing aortic arch surgery are survivors of emergent proximal aortic repair for acute dissection, and thus, these patients now face a reoperative procedure necessitating a redo median sternotomy. One approach for repairing the chronic type I aortic dissection incorporates total transverse aortic arch replacement with and without an elephant trunk extension; an elephant trunk extension is a useful strategy, because the proximal descending thoracic aorta is commonly ectatic or aneurysmal at the time of aortic arch repair-using an elephant trunk approach facilitates subsequent repair in the distal aorta. Patients with chronic DeBakey type I dissection should participate in an imaging surveillance protocol.

Activities at Thoracic Aortic Research Center, IRCCS Policlinico San Donato

The Thoracic Aortic Research Center (TARC) of the IRCCS Policlinico San Donato (PSD) aims to promote research on thoracic aortic diseases, to disclose the scientific knowledge and clinical experience and to develop new scientific paths within the Hospital and the aortic community, in collaboration with other national and international centres. Thoracic Aortic Research Center collaborates with many centres in both Europe (e.g. University of Utrecht, the Netherlands) and the USA (e.g. University of Michigan). This has led to multiple highly regarded publications in respected cardiovascular journals and has led to several PhD programmes resulting in doctorate degrees. Within Italy, in association with the Bioengineering School of the University of Pavia, TARC has founded the "BETA-lab" (Biomechanics for Endovascular Treatment of the Aorta laboratory), where MDs, Bioengineers, and PhD fellows conduct experimental studies using in vitro/ex vivo models of the physiologic aorta and aortic diseases. Furthermore, a database (iCardiocloud) where the medical imaging of cardiovascular patients from the PSD is structured, for in silico analysis utilizing computational fluid dynamics, and in vitro studies using also 3D printed aortic models. With the role of principal investigator or co-investigator, TARC at PSD has been participating in other several projects, including the International Registry of Acute Aortic Dissection, the International Aortic Arch Surgery Study Group, the European Registry of Endovascular Aortic Repair Complications, the ADSORB and ASSIST trials, and the GREAT registry. International collaborations have included also studies on predictors of aortic growth after dissection with the Yale University and University of Virginia, and on aortic biomarkers with the University of Tokyo.

Analysis of early and long-term outcomes of acute type A aortic dissection according to the new international aortic arch surgery study group recommendations

To evaluate predictors of early and long-term outcomes of surgical repair of acute Type A aortic dissection. Retrospective single-centre study evaluating patients surgically treated between 1998 and 2013. Clinical follow-up was performed. Complications were classified according to the International Aortic Arch Surgery Study Group recommendations. Statistical analysis included univariate and multivariate analysis of preoperative and operative data. One hundred eighty-five patients were evaluated. The follow-up was complete for 180 patients (97 %). Mean age was 63 years, 82 % had a DeBakey type I aortic dissection, 18 % a type II. Eleven patients (6 %) died intraoperatively, 119 of the remaining (68 %) had postoperative complications. Thirty-day mortality was 21 % (38 patients). Average ICU and hospital stay were 6 and 14 days, respectively. During a mean follow-up time of 6 ± 4 years we observed 44 deaths (31 %). Twenty patients (14 %) needed late thoracic aorta reoperation. Results from the multivariate analysis are as follows. Thirty-day mortality was associated with abdominal pain at presentation (p < 0.01). The incidence of postoperative complications was related to older age at intervention (p < 0.01) and longer cross-clamp time (p < 0.01). Mortality at follow-up was significantly increased by older age at intervention (p < 0.01), with a logarithmic growth after 60 years, female sex (p < 0.01), preoperative limb ischemia (p = 0.02) and DHCA (p < 0.01). The surgical results of type A aortic dissection are affected by age at intervention with a logarithmic increase of late mortality in patients older than 60 years.