Next-Generation Frozen Elephant Trunk Technique in the Era of Precision Medicine.

The frozen elephant trunk (FET) technique can be applied to extensive aortic pathology, including lesions in the aortic arch and proximal descending thoracic aorta. FET is useful for tear-oriented surgery in dissections, managing malperfusion syndrome, and promoting positive aortic remodeling. Despite these benefits, complications such as distal stent-induced new entry and spinal cord ischemia can pose serious problems with the FET technique. To prevent these complications, careful sizing and planning of the FET are crucial. Additionally, since the FET technique involves total arch replacement, meticulous surgical skills are essential, particularly for young surgeons. In this article, we propose several techniques to simplify surgical procedures, which may lead to better outcomes for patients with extensive aortic pathology. In the era of precision medicine, the next-generation FET device could facilitate the treatment of complex aortic diseases through a patient-tailored approach.

A novel hybrid prosthesis for open repair of acute DeBakey type I dissection with malperfusion: Early results from the PERSEVERE trial.

BACKGROUND: Outcomes after hemiarch repair for acute DeBakey type I aortic dissection (ADTI) remain unfavorable, with high rates of major adverse events and negative aortic remodeling. The PERSEVERE study evaluates the safety and effectiveness of the AMDS Hybrid prosthesis, a novel bare metal stent, in patients presenting with preoperative malperfusion. METHODS: PERSEVERE is a prospective single-arm investigational study conducted at 26 sites in the United States. Ninety-three patients underwent ADTI aortic dissection repair with AMDS implantation. The 30-day primary endpoints are a composite rate of 4 major adverse events and the rate of distal anastomotic new entry tears. The secondary endpoints include aortic remodeling. RESULTS: Clinical malperfusion was documented in 76 patients (82%); only radiographic malperfusion, in 17 (18%). The median follow-up in the 93 patients was 5.6 months. Within 30 days, 9 patients died (9.7%), 10 patients (10.8%) experienced new disabling stroke, and 18 patients (19.4%) had new-onset renal failure requiring ≥1 dialysis treatment. There were no cases of myocardial infarction. The composite rate of major adverse events (27%) was lower than that reported in the reference cohort (58%). There were no distal anastomotic new entry tears. Technical success was achieved in 99% of patients. Early remodeling indicated total aortic diameter stability, true lumen expansion, and false lumen reduction in the treated aortic segment. CONCLUSIONS: Early results show significant reductions in major adverse events and distal anastomotic new entry tears, successfully meeting both primary endpoints. The technical success rate was high. AMDS can be used safely in patients with ADTI dissection with malperfusion.

Long-Term Outcomes of Antegrade Thoracic Stent Grafting During Repair of Acute DeBakey I Dissection.

BACKGROUND: We aim to evaluate the impact of antegrade stenting of the distal arch and proximal descending aorta combined with non-total arch procedures in acute type A aortic dissection. METHODS: From 2005 to 2022, 733 nonsyndromic patients presented with acute DeBakey type I aortic dissection and underwent non-total arch procedure. Ninety-five patients underwent antegrade stenting and 638 did not. Propensity-score analysis was performed, and 95 optimal pairs were created. Survival was estimated using the Kaplan-Meier method and cumulative incidence of reintervention with death as a competing event was calculated and compared using Gray's method. RESULTS: Survival estimates at 10 years after propensity score matching were similar between both groups, 58.9% (95% CI, 46.5%-74.5%) vs 58.4% (95% CI, 48.3%-70.6%) (P = .6) in the non-stented vs stented group. Cumulative incidence of reintervention with competing risk of death at 10 years after propensity matching was 27% (95% CI, 17%-37%) vs 22% (95% CI, 14%-32%) (P = .44), respectively. CONCLUSIONS: Antegrade thoracic endovascular aortic repair may be beneficial for remodeling and facilitating future endovascular reinterventions and reduces the occurrence of reintervention for malperfusion.

Performance of the open-first repair strategy in type A aortic dissection with mesenteric malperfusion syndrome eligible for delayed repair.

OBJECTIVE: For patients with type A aortic dissection complicated by mesenteric malperfusion syndrome, some centers advocate a nontraditional approach based on up-front endovascular intervention and delayed open repair. However, the efficacy of this strategy cannot be understood without first understanding outcomes of the traditional open-first strategy in the same select patient population eligible for delayed repair, applying modern techniques of hybrid aortic surgery. METHODS: Patients with acute type A aortic dissection and mesenteric malperfusion syndrome were queried from a single institution. Those presenting with aortic rupture, tamponade, or cardiogenic shock (ineligible for delayed repair) were excluded. Patients were managed with immediate open aortic repair. Short-term and long-term outcomes are reported. RESULTS: A total of 1228 patients were treated for acute type A dissection in the study period, of whom 77 were included in the mesenteric malperfusion syndrome cohort. In-hospital mortality was 29% compared with 39% in an identically selected mesenteric malperfusion syndrome population undergoing delayed repair reported previously. Among patients with mesenteric malperfusion syndrome, 32% underwent additional procedures addressing distal malperfusion in a hybrid operating room during or after open repair. Concomitant proximal malperfusion (coronary, cerebral, or upper extremity) was common in the mesenteric malperfusion syndrome cohort, present in 35% of cases. Although early mortality was greater in the mesenteric malperfusion syndrome cohort compared with all acute type A dissections, 10-year survival among those discharged alive was similar (65% vs 59%, P = .18). CONCLUSIONS: The traditional open-first repair strategy performs equal to or better than the delayed repair strategy for patients with mesenteric malperfusion syndrome eligible for delayed repair.

The burden of major complications on failure to rescue after surgery for acute type A aortic dissection: Analysis of more than 19,000 patients.

BACKGROUND: The relationship between the number and type of postoperative complications and mortality in the setting for surgery for acute type A aortic dissection (ATAAD) remains underexplored despite its critical role in the failure-to-rescue (FTR) metric. METHODS: This retrospective study used data from the Society of Thoracic Surgeons Adult Cardiac Surgical Database on ATAAD surgeries performed between January 2018 and December 2022. Patients were categorized based on their number of major complications. The primary outcome was FTR. We used multilevel regression and classification and regression tree models. RESULTS: We included 19,243 patients (33% females), with a median age of 61 years. Regarding complications, 47.7% of patients had 0, 20.2% had 1, 12.7% had 2, and 19.4% experienced 3 or more. The most frequently reported complications were prolonged mechanical ventilation (30.3%), unplanned reoperation (19.5%), and renal failure (17.2%). Cardiac arrest occurred in 7.1% of cases. FTR increased from 13% in patients with 1 complication to >30% in those with 4 or more complications. Cardiac arrest (adjusted odds ratio [aOR], 10.9) and renal failure (aOR, 5.3) had the highest odds for mortality, followed by limb ischemia (aOR, 2.7), stroke (aOR, 2.6), and gastrointestinal complications (aOR, 2.4). Hospitals in the top performance quartile consistently showed lower FTR rates across all levels of complication. CONCLUSIONS: The study validates a dose-response association between postoperative complications and mortality in patients undergoing surgery for ATAAD. Top-performing hospitals consistently show lower FTR rates independent of the number of complications. Future research should focus on the timing of complications and interventions to reduce the burden of complications.

Predictors and 5-Year Clinical Outcomes of Pacemaker After TAVR: Analysis From the PARTNER 2 SAPIEN 3 Registries.

BACKGROUND: Conduction disturbances requiring a permanent pacemaker (PPM) are a frequent complication of transcatheter aortic valve replacement (TAVR) with few reports of rates, predictors, and long-term clinical outcomes following implantation of the third-generation, balloon-expandable SAPIEN 3 (S3) transcatheter heart valve (THV). OBJECTIVES: The aim of this study was to investigate the rates, predictors, and long-term clinical outcomes of PPM implantation following TAVR with the S3 THV. METHODS: The current study included 857 patients in the PARTNER 2 S3 registries with intermediate and high surgical risk without prior PPM, and investigated predictors and 5-year clinical outcomes of new PPM implanted within 30 days of TAVR. RESULTS: Among 857 patients, 107 patients (12.5%) received a new PPM within 30 days after TAVR. By multivariable analysis, predictors of PPM included increased age, pre-existing right bundle branch block, larger THV size, greater THV oversizing, moderate or severe annulus calcification, and implantation depth >6 mm. At 5 years (median follow-up 1,682.0 days [min 2.0 days, max 2,283.0 days]), new PPM was not associated with increased rates of all-cause mortality (Adj HR: 1.20; 95% CI: 0.85-1.70; P = 0.30) or repeat hospitalization (Adj HR: 1.22; 95% CI: 0.67-2.21; P = 0.52). Patients with new PPM had a decline in left ventricular ejection fraction at 1 year that persisted at 5 years (55.1 ± 2.55 vs 60.4 ± 0.65; P = 0.02). CONCLUSIONS: PPM was required in 12.5% of patients without prior PPM who underwent TAVR with a SAPIEN 3 valve in the PARTNER 2 S3 registries and was not associated with worse clinical outcomes, including mortality, at 5 years. Modifiable factors that may reduce the PPM rate include bioprosthetic valve oversizing, prosthesis size, and implantation depth.

Transcriptomic responses of peripheral blood leukocytes to cardiac surgery after acute inflammation, and three months recovery.

Traumatic perioperative conditions may trigger early systemic responses, activate leukocytes and reprogram the immune system. We hypothesize that leukocyte activation may not revert to pre-surgical states, and that protracted activation may emerge with increased risks of comorbidities. We tested this concept by examining the transcriptomes of monocytes and T cells in a representative observational cohort of patients (n = 13) admitted for elective cardiac surgery. Transcriptomes in T cells and monocytes were compared from before surgery (t0), and monocytes were analyzed longitudinally after acute (t24hr), and convalescent (t3m) time points. Monocytes and T cells expressed distinct transcriptomes, reflected by statistically significant differential expression of 558 T cell related genes. Monocytes expressed genes related to protein degradation and presented atypical activation of surface markers and cytoplasmic functions over time. Additionally, monocytes exhibited limited transcriptomic heterogeneity prior to surgery, and long-term patterns of gene expression associated with atherosclerosis showed three temporally distinct signatures. These data establish that post-cardiac surgery transcriptomes of monocytes differ even at three months compared to baselines, which may reflect latent ('smoldering') inflammation and persistent progression of tissue degenerative processes that should inform clinical care.

Middle and High School LGBTQ Students Report What Makes School LGBTQ-Affirming Across Race/Ethnicity and Gender Identity, a Topic Modeling Method.

BACKGROUND: Affirming spaces have been associated with improved mental health outcomes for lesbian, gay, bisexual, transgender, queer, and questioning (LGBTQ) adolescents. METHODS: With data from adolescents currently enrolled in middle or high school across the United States, this study used topic modeling methods to examine students' reports of what they were looking for in LGBTQ-affirming schools and, separately, the association of LGBTQ-affirming schools with suicide risk reduction. RESULTS: Topic models demonstrated consistent themes in how students determined that their school was affirming, such as LGBTQ clubs, teachers requesting pronouns, pride flags, and accepting peers. Students of color uniquely looked for actionable responses in addressing LGBTQ issues. Transgender and nonbinary students required explicit mention of support for transgender issues. Quantitatively, LGBTQ students who reported that their school was LGBTQ-affirming had 20% lower odds of attempting suicide in the past year (adjusted odds ratio = 0.80). CONCLUSIONS: These findings suggest that schools must be safe for all youth and implementing policies that make LGBTQ students feel seen and supported in their identities is a protective factor for mental health. IMPLICATIONS: School policies must ensure that youth have access to supportive people, symbols of support, and LGBTQ clubs and that they are also salient to LGBTQ students of color and transgender and nonbinary students.

Case report: Therapy-related myeloid neoplasms in three pediatric cases with medulloblastoma.

Introduction: Medulloblastoma is the most common malignant brain tumor in children, often requiring intensive multimodal therapy, including chemotherapy with alkylating agents. However, therapy-related complications, such as therapy-related myeloid neoplasms (t-MNs), can arise, particularly in patients with genetic predisposition syndromes. This case report presents three pediatric cases of medulloblastoma with subsequent development of t-MNs, highlighting the potential role of genetic predisposition and the importance of surveillance for hematological abnormalities in long-term survivors. Case presentation: We describe three cases of pediatric medulloblastoma who developed t-MNs after receiving chemotherapy, including alkylating agents. Two of the patients had underlying genetic predisposition syndromes (TP53 pathologic variants). The latency period between initial diagnosis of medulloblastoma and the development of secondary cancer varied among the cases, ranging from 17 to 65 months. The three cases eventually succumbed from secondary malignancy, therapy-related complications and progression of primary disease, respectively. Conclusions: This report highlights the potential association between genetic predisposition syndromes and the development of therapy-related myeloid neoplasms in pediatric medulloblastoma survivors. It underscores the importance of surveillance for hematological abnormalities among such patients.

Transcatheter aortic valve replacement achieves similar predicted effective orifice area to surgical aortic valve replacement in bicuspid aortic stenosis.

BACKGROUND: Studies comparing transcatheter and surgical aortic valve replacement (TAVR and SAVR) for patients with trileaflet aortic stenosis (AS) have found similar or larger effective orifice area (EOA) for TAVR prostheses. To our knowledge, no studies have compared EOA in patients undergoing TAVR versus SAVR for bicuspid AS. METHODS: We retrospectively compared prosthetic valvular sizing and predicted EOA for patients with bicuspid AS undergoing TAVR or SAVR at our institution between January 1, 2016, and December 31, 2021. We excluded patients undergoing procedures for indications other than AS and those without a pre-procedural gated Chest CT. Comparisons included demographics, comorbidities, annular size, prosthetic valve size, predicted EOA and prosthesis-patient mismatch (PPM) for TAVR (N = 78) and SAVR (N = 74) cohorts. RESULTS: TAVR patients had smaller pre-procedural annular area (501.7 mm2 vs. 571.8 mm2, p < 0.05) and annular perimeter (80.6 mm vs. 86.5 mm, p < 0.05), but larger mean implanted prosthetic valve size (26.4 mm vs 24.2 mm, p < 0.001) compared to SAVR patients. No differences were observed in predicted EOA, predicted EOA indexed to patient body surface area (EOAi), or predicted PPM grade between TAVR and SAVR groups, including in cohorts sorted by pre-procedural annular size. CONCLUSIONS: For bicuspid AS patients undergoing aortic valve replacement, TAVR achieves similar predicted EOA to SAVR. These data support the use of TAVR in selected patients with bicuspid AS and can inform heart team discussions.

Patient-Prosthesis Mismatch After Surgical Aortic Valve Replacement: Analysis of the PARTNER Trials.

BACKGROUND: Our objective was to compare the impact of patient-prosthesis mismatch (PPM) for 2 years after surgical aortic valve replacement within the prospective, randomized Placement of Aortic Transcatheter Valves (PARTNER) trials. METHODS: Surgical aortic valve replacement patients from the PARTNER 1, 2, and 3 trials were included. PPM was classified as moderate (indexed effective orifice area ≤0.85 cm2/m2) or severe (indexed effective orifice area ≤0.65 cm2/m2). The primary endpoint was the composite of all-cause death and heart failure rehospitalization at 2 years. RESULTS: By the predicted PPM method (PPMP), 59.1% had no PPM, 38.8% moderate PPM, and 2.1% severe PPM; whereas by the measured PPM method (PPMM), 42.4% had no PPM, 36.0% moderate, and 21.6% severe. Patients with no PPMP (23.6%) had a lower rate of the primary endpoint compared with patients with moderate (28.2%, P = .03) or severe PPMP (38.8%, P = .02). Using the PPMM method, there was no difference between the no (17.7%) and moderate PPMM groups (21.1%) in the primary outcome (P = .16). However, those with no PPMM or moderate PPMM were improved compared with severe PPMM (27.4%, P < .001 and P = .02, respectively). CONCLUSIONS: Severe PPM analyzed by PPMP was only 2.1% for surgical aortic valve replacement patients. The PPMM method overestimated the incidence of severe PPM relative to PPMP, but was also associated with worse outcome. There was higher all-cause mortality in patients with severe PPM, thus surgical techniques to minimize PPM remain critical.

Prevalence and Outcomes of Infections in Critically-ill Paediatric Oncology Patients: A Retrospective Observation Study.

PURPOSE: The survival of paediatric oncology patients has improved substantially in the past decades due to advances in the field of oncology. Modern cancer treatments often come with life-threatening complications, of which infection is one of the most common causes in this patient population. This study aims to investigate the prevalence and outcomes of common infections in haemato-oncology patients during their stay in paediatric intensive care unit (PICU) and to identify any factors associated with these infections. METHODS: A retrospective observational study was conducted on all children with a haemato-oncology diagnosis or who underwent haematopoietic stem cell transplantation (HSCT) and who were admitted to the Hong Kong Children's Hospital PICU over a one-year period. Infection characteristics and patient outcomes were evaluated and compared between different sub-groups. Univariable and multi-variable analyses were employed to identify risk factors associated with the development of active infection. RESULTS: Forty-five (36.3%) of 124 critically ill haemato-oncology admissions to PICU were associated with infections, of which 31 (25%) admissions involved bacterial infections, 26 (20.9%) involved viral infections and 6 (4.8%) involved fungal infections. Bloodstream infection was the most common type of infection. More than half (61.3%) of the bacterial infections were due to an antibiotic-resistant strain. After adjusting for confounding variables, post-HSCT status and neutropenia were significantly associated with active infections. CONCLUSION: Infections in critically-ill haemato-oncological patients are associated with post haematopoietic stem cell transplant status and neutropenia. Further study is warranted to review effective strategies that may mitigate the likelihood of infection in this patient population.

The non to moderately dilated root in acute type A aortic dissection: outcomes of the PENN-BERN registry in young, non-syndromic patients.

OBJECTIVES: There is an ongoing debate regarding whether patients benefit more from root replacement compared to a reconstruction of the sinuses of Valsalva in acute type A aortic dissection (aTAAD). In those with known or suspected connective tissue disorders, root replacement is considered appropriate. However, there are currently no diameter-based guidelines regarding the best approach in patients with minimally to moderately dilated root and no connective tissue disorders. METHODS: From January 2005 to December 2022, a two-centre registry of aTAAD was created. Patients were included based on their age (≤60 years), the absence of root entry and dilatation >50 mm and the absence of syndromic hereditable aortic disease. Patients were divided into 2 groups based on the proximal procedure, root reconstruction and root replacement. Propensity score pair matching was performed based on preoperative characteristics. RESULTS: Cumulative incidence of reintervention at 10 years was slightly higher after root reconstruction 13% vs 3.9% in the matched group (P = 0.040). Survival at 10 years was not affected by the procedure independently of the matching 72.1% vs 71.4% (P = 0.2). Uni- and multivariate Cox regressions showed that a root diameter of >40 mm was associated with a hazard ratio of 7.7 (95% confidence interval 2.6-23) and 5.4 (7-17), respectively, for reoperation for aneurysm and pseudoaneurysm. CONCLUSIONS: Rate of reoperation due to proximal pseudoaneurysm and aneurysm could be significantly reduced with a lower threshold of 40 mm to replace the aortic root in aTAAD than in elective cases.

Survival After Surgical Aortic Valve Replacement in Low-Risk Patients: A Contemporary Trial Benchmark.

BACKGROUND: The use of transcatheter aortic valve replacement for severe aortic stenosis in low-risk patients necessitates an evaluation of contemporary long-term, real-world outcomes of similar patients undergoing surgical aortic valve replacement (SAVR) in a national cohort. METHODS: All patients undergoing primary, isolated SAVR in The Society of Thoracic Surgeons (STS) database between 2011 and 2019 were examined. The study population of 42,586 adhered to the inclusion/exclusion criteria of the Placement of Aortic Transcatheter Valves (PARTNER) 3 and Evolut Low Risk randomized trials. Patients were further stratified by STS predicted risk of mortality (PROM), age, and left ventricular ejection fraction. The primary end-point was all-cause National Death Index mortality. Unadjusted survival to 8 years was estimated using the Kaplan-Meier method. RESULTS: Mean age was 74.3 ± 5.7 years and mean STS PROM was 1.9% ± 0.8%. The overall Kaplan-Meier time to event analysis for all-cause mortality at 1, 3, 5, and 8 years was 2.6%, 4.5%, 7.1%, and 12.4%, respectively. In subset analyses, survival was significantly better for (1) lower STS PROM (P < .001), (2) younger vs older age (P < .001), and (3) higher vs lower left ventricular ejection fraction (P < .001). When STS PROM was below 1% or the patient age was below age 75 years, the 8-year survival after SAVR was 95%. CONCLUSIONS: The results of this national study confirm that long-term survival after SAVR remains excellent, at 92.9% at 5 years. These contemporary longitudinal data serve to aid in the balanced interpretation of current and future trials comparing SAVR and transcatheter aortic valve replacement and may assist in the clinical decision-making process for patients of lower surgical risk.

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.

The impact of reoperative surgery on aortic root replacement in the United States.

OBJECTIVE: Reoperative sternotomy is associated with poor outcomes after cardiac surgery. We aimed to investigate the impact of reoperative sternotomy on the outcomes after aortic root replacement. METHODS: All patients who underwent aortic root replacement from January 2011 to June 2020 were identified using the Society of Thoracic Surgeons Adult Cardiac Surgery Database. We compared outcomes between patients who underwent first-time aortic root replacement with those with a history of sternotomy undergoing reoperative sternotomy aortic root replacement using propensity score matching. Subgroup analysis was performed among the reoperative sternotomy aortic root replacement group. RESULTS: A total of 56,447 patients underwent aortic root replacement. Among them, 14,935 (26.5%) underwent reoperative sternotomy aortic root replacement. The annual incidence of reoperative sternotomy aortic root replacement increased from 542 in 2011 to 2300 in 2019. Aneurysm and dissection were more frequently observed in the first-time aortic root replacement group, whereas infective endocarditis was more common in the reoperative sternotomy aortic root replacement group. Propensity score matching yielded 9568 pairs in each group. Cardiopulmonary bypass time was longer in the reoperative sternotomy aortic root replacement group (215 vs 179 minutes, standardized mean difference = 0.43). Operative mortality was higher in the reoperative sternotomy aortic root replacement group (10.8% vs 6.2%, standardized mean difference = 0.17). In the subgroup analysis, logistic regression demonstrated that individual patient repetition of (second or more resternotomy) surgery and annual institutional volume of aortic root replacement were independently associated with operative mortality. CONCLUSIONS: The incidence of reoperative sternotomy aortic root replacement might have increased over time. Reoperative sternotomy is a significant risk factor for morbidity and mortality in aortic root replacement. Referral to high-volume aortic centers should be considered in patients undergoing reoperative sternotomy aortic root replacement.

Validation of the GERAADA score to predict 30-day mortality in acute type A aortic dissection in a single high-volume aortic centre.

OBJECTIVES: This study aimed to evaluate employing the German Registry of Acute Aortic Dissection Type A (GERAADA) score to predict 30-day mortality in an aortic centre in the USA. METHODS: Between January 2010 and June 2021, 689 consecutive patients underwent surgery for acute type A dissection at a single institution. Excluded were patients with missing clinical data (N = 4). The GERAADA risk score was retrospectively calculated via a web-based application. Model discrimination power was calculated with c-statistics from logistic regression and reported as the area under the receiver operating characteristic curve with 95% confidence intervals. The calibration was measured by calculating the observed versus estimated mortality ratio. The Brier score was used for the overall model evaluation. RESULTS: Included were 685 patients [mean age 60.6 years (SD: 13.5), 64.8% male] who underwent surgery for acute type A aortic dissection. The 30-day mortality rate was 12.0%. The GERAADA score demonstrated very good discrimination power with an area under the receiver operating characteristic curve of 0.762 (95% confidence interval 0.703-0.821). The entire cohort's observed versus estimated mortality ratio was 0.543 (0.439-0.648), indicating an overestimation of the model-calculated risk. The Brier score was 0.010, thus revealing the model's acceptable overall performance. CONCLUSIONS: The GERAADA score is a practical and easily accessible tool for reliably estimating the 30-day mortality risk of patients undergoing surgery for acute type A aortic dissection. This model may naturally overestimate risk in patients undergoing surgery in experienced aortic centres.

Transient fertilization of a post-Sturtian Snowball ocean margin with dissolved phosphate by clay minerals.

Marine sedimentary rocks deposited across the Neoproterozoic Cryogenian Snowball interval, ~720-635 million years ago, suggest that post-Snowball fertilization of shallow continental margin seawater with phosphorus accelerated marine primary productivity, ocean-atmosphere oxygenation, and ultimately the rise of animals. However, the mechanisms that sourced and delivered bioavailable phosphate from land to the ocean are not fully understood. Here we demonstrate a causal relationship between clay mineral production by the melting Sturtian Snowball ice sheets and a short-lived increase in seawater phosphate bioavailability by at least 20-fold and oxygenation of an immediate post-Sturtian Snowball ocean margin. Bulk primary sediment inputs and inferred dissolved seawater phosphate dynamics point to a relatively low marine phosphate inventory that limited marine primary productivity and seawater oxygenation before the Sturtian glaciation, and again in the later stages of the succeeding interglacial greenhouse interval.