Heart Transplant Human Leukocyte Antigen Matching in the Modern Era.

BACKGROUND: Although numerous reports have studied the consequences of human leukocyte antigen (HLA) mismatching in renal transplantation, there are limited and outdated data analyzing this association in thoracic organ transplantation. Therefore, our study reviewed the impact of HLA mismatching at both the total and the loci levels in the modern-era heart-transplant procedure on survival and chronic rejection outcomes. METHODS: We performed a retrospective analysis of adult patients after heart transplant by using the United Network for Organ Sharing database from January 2005-July 2021. Total HLA and HLA-A, HLA-B and HLA-DR mismatches were analyzed. Survival and cardiac allograft vasculopathy were the outcomes of interest during a 10-year follow-up period using Kaplan-Meier curves, log-rank tests and multivariable regression models. RESULTS: A total of 33,060 patients were included in this study. Recipients with a high degree of HLA mismatching had increased incidences of acute organ rejection. There were no significant differences in mortality rates among any of the total or loci level groups. Similarly, there were no significant differences between total HLA mismatch groups in time to first cardiac allograft vasculopathy, though mismatching at the HLA-DR locus was associated with an increased risk of cardiac allograft vasculopathy. CONCLUSION: Our analysis suggests that HLA mismatch is not a significant predictor of survival in the modern era. Overall, the clinical implications of this study provide reassuring data for the continued use of non-HLA-matched donors in an effort to increase the donor pool. If HLA matching is to be considered for heart transplant donor-recipient selection, matching at the HLA-DR locus should take priority due to its association with cardiac allograft vasculopathy.

Impact of donor ventricular function on heart transplantation outcomes.

BACKGROUND: Some heart transplant (HTx) centers have expanded their donor eligibility criteria in response to the organ shortage; one area of active interest involves utilizing hearts with ventricular dysfunction. Our study seeks to identify if a relationship exists between donor left ventricular ejection fraction (LVEF) and ischemic time or donor age on HTx outcomes. METHODS: We performed a retrospective analysis on adult patients who had a HTx between 1996 and 2021 (n = 46,936). Donor LVEF (dLVEF) values were categorized into three groups: <50%, 50%-70%, and >70%. Ischemic time and donor age were stratified into four groups: ≤2.0, 2.1-3.0, 3.1-4.0, >4.0 h, and ≤30, 31-40, 41-50, >50 years, respectively. The outcome of interest was long-term survival. RESULTS: Multivariable survival analysis found a slight increase in overall mortality risk for patients with donor ejection fractions <50% (HR = 1.16, p = .013). However, subsequent subgroup investigation discovered that this elevated hazard was only applicable when ischemic time was prolonged to >3.0 h (3.1-4.0 h: HR = 1.23, p = .024; > 4.0 h: HR = 1.52, p < .001). There was no significant difference in survival between dLVEF groups when ischemic time was limited to ≤3.0 h or when stratified by donor age. CONCLUSION: HTx patients with a low donor ejection fraction have comparable survival to recipients with a normal dLVEF when ischemic time is limited to ≤3.0 h. Reduced dLVEF does not appear to be sensitive to advanced donor age. The clinical implications of our study may encourage the recruitment of more donor hearts for transplantation.

Cardiac tamponade masquerading as headache: A diagnostic conundrum.

Cardiac tamponade and its protean presentations are well documented. Tamponade presenting after recent cardiac surgery in a patient on anticoagulation is not unknown. However, severe headache as a presenting feature of tamponade is not documented. We describe how one can be misled into investigating causes of headache while the real cause, tamponade, lies hidden.

Exposure of Rat Neural Stem Cells to Ethanol Affects Cell Numbers and Alters Expression of 28 Proteins.

Developing brain cells express many proteins but little is known of how their protein composition responds to chronic exposure to alcohol and/or how such changes might relate to alcohol toxicity. We used cultures derived from embryonic rat brain (previously shown to contain mostly neural stem cells; rat NSC, rNSC), exposed them to ethanol (25-100 mM) for up to 96 h and studied how they reacted. Ethanol (50 and 100 mM) reduced cell numbers indicating either compromised cell proliferation, cytotoxicity or both. Increased lipid peroxidation was consistent with the presence of oxidative stress accompanying alcohol-induced cytotoxicity. Proteomics revealed 28 proteins as altered by ethanol (50 mM for 96 h). Some were constituents of cytoskeleton, others were involved in transcription/translation, signal transduction and oxidative stress. Nucleophosmin (NPM1) and dead-end protein homolog 1 (DND1) were further studied by immunological techniques in cultured neurons and astrocytes (derived from brain tissue at embryonic ages E15 and E20, respectively). In the case of DND1 (but not NPM1) ethanol induced similar pattern of changes in both types of cells. Given the critical role of the protein NPM1 in cell proliferation and differentiation, its reduced expression in the ethanol-exposed rNSC could, in part, explain the lower cells numbers. We conclude that chronic ethanol profoundly alters protein composition of rNSC to the extent that their functioning-including proliferation and survival-would be seriously compromised. Translated to humans, such changes could point the way towards mechanisms underlying the fetal alcohol spectrum disorder and/or alcoholism later in life.

BI 1002494, a Novel Potent and Selective Oral Spleen Tyrosine Kinase Inhibitor, Displays Differential Potency in Human Basophils and B Cells.

BI 1002494 [(R)-4-{(R)-1-[7-(3,4,5-trimethoxy-phenyl)-[1,6]napthyridin-5-yloxy]-ethyl}pyrrolidin-2-one] is a novel, potent, and selective spleen tyrosine kinase (SYK) inhibitor with sustained plasma exposure after oral administration in rats, which qualifies this molecule as a good in vitro and in vivo tool compound. BI 1002494 exhibits higher potency in inhibiting high-affinity IgE receptor-mediated mast cell and basophil degranulation (IC50 = 115 nM) compared with B-cell receptor-mediated activation of B cells (IC50 = 810 nM). This may be explained by lower kinase potency when the physiologic ligand B-cell linker was used, suggesting that SYK inhibitors may exhibit differential potency depending on the cell type and the respective signal transduction ligand. A 3-fold decrease in potency was observed in rat basophils (IC50 = 323 nM) compared with human basophils, but a similar species potency shift was not observed in B cells. The lower potency in rat basophils was confirmed in both ex vivo inhibition of bronchoconstriction in precision-cut rat lung slices and in reversal of anaphylaxis-driven airway resistance in rats. The different cellular potencies translated into different in vivo efficacy; full efficacy in a rat ovalbumin model (that contains an element of mast cell dependence) was achieved with a trough plasma concentration of 340 nM, whereas full efficacy in a rat collagen-induced arthritis model (that contains an element of B-cell dependence) was achieved with a trough plasma concentration of 1400 nM. Taken together, these data provide a platform from which different estimates of human efficacious exposures can be made according to the relevant cell type for the indication intended to be treated.

Metabolomics of Neurotransmitters and Related Metabolites in Post-Mortem Tissue from the Dorsal and Ventral Striatum of Alcoholic Human Brain.

We report on changes in neurotransmitter metabolome and protein expression in the striatum of humans exposed to heavy long-term consumption of alcohol. Extracts from post mortem striatal tissue (dorsal striatum; DS comprising caudate nucleus; CN and putamen; P and ventral striatum; VS constituted by nucleus accumbens; NAc) were analysed by high performance liquid chromatography coupled with tandem mass spectrometry. Proteomics was studied in CN by two-dimensional gel electrophoresis followed by mass-spectrometry. Proteomics identified 25 unique molecules expressed differently by the alcohol-affected tissue. Two were dopamine-related proteins and one a GABA-synthesizing enzyme GAD65. Two proteins that are related to apoptosis and/or neuronal loss (BiD and amyloid-ß A4 precursor protein-binding family B member 3) were increased. There were no differences in the levels of dopamine (DA), 3,4-dihydrophenylacetic acid (DOPAC), serotonin (5HT), homovanillic acid (HVA), 5-hydroxyindoleacetic acid (HIAA), histamine, L-glutamate (Glu), γ-aminobutyric acid (GABA), tyrosine (Tyr) and tryptophan (Tryp) between the DS (CN and P) and VS (NAc) in control brains. Choline (Ch) and acetylcholine (Ach) were higher and norepinephrine (NE) lower, in the VS. Alcoholic striata had lower levels of neurotransmitters except for Glu (30 % higher in the alcoholic ventral striatum). Ratios of DOPAC/DA and HIAA/5HT were higher in alcoholic striatum indicating an increase in the DA and 5HT turnover. Glutathione was significantly reduced in all three regions of alcohol-affected striatum. We conclude that neurotransmitter systems in both the DS (CN and P) and the VS (NAc) were significantly influenced by long-term heavy alcohol intake associated with alcoholism.

GLAST But Not Least--Distribution, Function, Genetics and Epigenetics of L-Glutamate Transport in Brain--Focus on GLAST/EAAT1.

Synaptically released L-glutamate, the most important excitatory neurotransmitter in the CNS, is removed from extracellular space by fast and efficient transport mediated by several transporters; the most abundant ones are EAAT1/GLAST and EAAT2/GLT1. The review first summarizes their location, functions and basic characteristics. We then look at genetics and epigenetics of EAAT1/GLAST and EAAT2/GLT1 and perform in silico analyses of their promoter regions. There is one CpG island in SLC1A2 (EAAT2/GLT1) gene and none in SLC1A3 (EAAT1/GLAST) suggesting that DNA methylation is not the most important epigenetic mechanism regulating EAAT1/GLAST levels in brain. There are targets for specific miRNA in SLC1A2 (EAAT2/GLT1) gene. We also note that while defects in EAAT2/GLT1 have been associated with various pathological states including chronic neurodegenerative diseases, very little is known on possible contributions of defective or dysfunctional EAAT1/GLAST to any specific brain disease. Finally, we review evidence of EAAT1/GLAST involvement in mechanisms of brain response to alcoholism and present some preliminary data showing that ethanol, at concentrations which may be reached following heavy drinking, can have an effect on the distribution of EAAT1/GLAST in cultured astrocytes; the effect is blocked by baclofen, a GABA-B receptor agonist and a drug potentially useful in the treatment of alcoholism. We argue that more research effort should be focused on EAAT1/GLAST, particularly in relation to alcoholism and drug addiction.

Ethanol, not detectably metabolized in brain, significantly reduces brain metabolism, probably via action at specific GABA(A) receptors and has measureable metabolic effects at very low concentrations.

Ethanol is a known neuromodulatory agent with reported actions at a range of neurotransmitter receptors. Here, we measured the effect of alcohol on metabolism of [3-¹³C]pyruvate in the adult Guinea pig brain cortical tissue slice and compared the outcomes to those from a library of ligands active in the GABAergic system as well as studying the metabolic fate of [1,2-¹³C]ethanol. Analyses of metabolic profile clusters suggest that the significant reductions in metabolism induced by ethanol (10, 30 and 60 mM) are via action at neurotransmitter receptors, particularly α4ß3δ receptors, whereas very low concentrations of ethanol may produce metabolic responses owing to release of GABA via GABA transporter 1 (GAT1) and the subsequent interaction of this GABA with local α5- or α1-containing GABA(A)R. There was no measureable metabolism of [1,2-¹³C]ethanol with no significant incorporation of ¹³C from [1,2-¹³C]ethanol into any measured metabolite above natural abundance, although there were measurable effects on total metabolite sizes similar to those seen with unlabelled ethanol.

Neuroadaptations in the striatal proteome of the rat following prolonged excessive sucrose intake.

Obesity is a contemporary health problem of rapidly increasing prevalence. One possible cause of obesity is loss of control over consumption of highly palatable foodstuffs, perhaps mirroring the processes involved in drug addiction. Accordingly, the striatum may be a key neural substrate involved in both food and drug craving. We hypothesised here that prolonged exposure to 10% sucrose solution might cause neuroadaptations in the striatum that are analogous to those previously reported following prolonged exposure to alcohol or recreational drugs. Male Wistar rats were given constant access to 10% sucrose solution (in addition to normal lab chow and tap water) for 8 months and were compared with control rats receiving no sucrose access. Rats in the sucrose group typically drank more than 100 ml of sucrose solution per day and showed 13% greater body weight than controls at the end of the 8 months. Striatal dopamine (DA) concentrations were decreased in the sucrose group rats relative to controls. Differential expression of 18 proteins was identified in the striatum of the sucrose group rats relative to controls. Down regulated proteins included pyridoxal phosphate phosphatase, involved in DA synthesis, and glutathione transferase, involved in free radical scavenging. Up regulated proteins included prolactin (which is under negative regulation by DA) and adipose differentiation-related protein, involved in fat synthesis. We hypothesise that DA-related neuroadaptations in the striatum caused by prolonged sucrose intake may partly drive compulsive intake and seeking of high palatability foodstuffs, in a similar way to that observed with drug and alcohol addictions.

3-Year Left Ventricular Assist Device Outcomes and Strategy After Heart Transplant Allocation Score Change.

BACKGROUND: The United Network for Organ Sharing (UNOS) adopted new criteria for the heart allocation score on 10/18/2018 to reflect changing trends of candidates' mortality while awaiting transplant. We examined the impact of these policy changes on rates of left ventricular assist device (LVAD) implantation and outcomes posttransplant from a relatively newer UNOS database. METHODS: The UNOS registry was used to identify first-time adult heart recipients with LVAD at listing or transplant who underwent transplantation between 1/1/2016 and 3/10/2020. Survival data was collected through 3/30/2023. Those listed prior to 10/18/2018 but transplanted after were excluded. Patients were divided into before or after change groups. Demographics and clinical parameters were compared. Survival was analyzed with Kaplan-Meier curves and log-rank tests. A p<0.05 was considered significant. RESULTS: We identified 4387 heart recipients with LVAD in the before (n=3606) and after (n=781) score change eras. The after group had a lower rate of LVAD implantation while listed compared to the before group (20.4% vs 34.9%, p<0.0001), and were more likely to be female (25.1% vs 20.2%, p=0.002); in both groups, most recipients (62.8%) were white. There was significantly farther distance from the donor hospital to transplant center in the after group (264.4 NM vs 144.2NM, p<0.0001) and decreased waitlist days (84.9 ± 105.1 vs 369.2 ± 459.5, p<0.0001). Recipients in the after group were more likely to utilize ECMO (3.7% vs 0.5%, p<0.0001) and IV inotropes (19.1% vs 7.5%, p<0.0001), and receive a CDC increased-risk donor organ (37.9% vs 30.5%, p<0.0001). Survival at 3-years was comparable between the two groups. CONCLUSIONS: The allocation score change in 2018 yielded considerable changes in mechanical circulatory support device implantation strategy and outcomes. The rate of LVAD implantation decreased with increased utilization of temporary mechanical circulatory support devices.

A single-centre analysis of lung transplantation outcomes in recipients aged 70 or older.

OBJECTIVES: As life expectancies continue to increase, a greater proportion of older patients will require lung transplants (LTs). However, there are no well-defined age cutoffs for which LT can be performed safely. At our high-volume LT centre, we explored outcomes for LT recipients ≥70 vs <70 years old. METHODS: This is a retrospective single-centre study of survival after LT among older recipients. Data were stratified by recipient age (≥70 vs <70 years old) and procedure type (single versus double LT). Demographics and clinical variables were compared using Chi-square test and 2 sample t-test. Survival was assessed by Kaplan-Meier curves and compared by log-rank test with propensity score matching. RESULTS: A total of 988 LTs were performed at our centre over 10 years, including 289 LTs in patients ≥70 years old and 699 LTs in patients <70 years old. The recipient groups differed significantly by race (P < 0.0001), sex (P = 0.003) and disease aetiology (P < 0.0001). Older patients were less likely to receive a double LT compared to younger patients (P < 0.0001) and had lower rates of intraoperative cardiopulmonary bypass (P = 0.019) and shorter length of stay (P = 0.001). Both groups had overall high 1-year survival (85.8% vs 89.1%, respectively). Survival did not differ between groups after propensity matching (P = 0.15). CONCLUSIONS: Our data showed high survival for older and younger LT recipients. There were no statistically significant differences observed in survival between the groups after propensity matching, however, a trend in favour of younger patients was observed.

Managing hypertension in urban underserved subjects using telemedicine--a clinical trial.

BACKGROUND: We evaluated an Internet- and telephone-based telemedicine system for reducing blood pressure (BP) in underserved subjects with hypertension. METHODS: A total of 241 patients with systolic BP ≥140 mm Hg were randomized to usual care (C; n = 121) or telemedicine (T; n = 120). The T group reported BP, heart rate, weight, steps/day, and tobacco use twice weekly. The primary outcome was BP control at 6 months. RESULTS: Average age was 59.6 years, average body mass index was 33.7 kg/m(2), 79% were female, 81% were African American, 15% were white, 53% were at or below the federal poverty level, 18% were smokers, and 32% had diabetes. Six-month follow-up was achieved in 206 subjects (C: 107, T: 99). Goal BP was achieved in 52.3% in C and 54.5% in T (P = .43). Systolic BP change (C: -13.9 mm Hg, T: -18.2; P = .118) was similar in both groups. Subjects in the T group reported BP 7.7 ± 6.9 d/mo. Results were not affected by age, sex, ethnicity, education, or income. In nondiabetic T subjects, goal BP was achieved in 58.2% compared with 45.2% of diabetic T subjects (P = .024). Nondiabetic T subjects demonstrated a greater reduction in systolic BP (T: -19 ± 20 mm Hg, C: -12 ± 19 mm Hg; P = .037). No difference in BP response between C and T was noted in patients with diabetes. CONCLUSION: In hypertensive subjects, engagement in a system of care with or without telemedicine resulted in significant BP reduction. Telemedicine for nondiabetic patients resulted in a greater reduction in systolic BP compared with usual care. Telemedicine may be a useful tool for managing hypertension particularly among nondiabetic subjects.

Right Coronary Artery Button Pseudoaneurysm After the Modified Bentall Procedure.

Anastomoses of the coronary buttons are the Achilles' heel of the modified Bentall procedure (MBP) for the repair of the aortic root and ascending aorta. We present a rare case of post-MBP right coronary artery button pseudoaneurysm in a 30-year-old man. The contained leak, attributed to a pseudoknot in the polypropylene suture, was visualized via computed tomography angiography and transesophageal echocardiogram and repaired under deep hypothermic circulatory arrest.

Red Blood Cell Transfusion Prior to Lung Transplantation: Impact on Patient Outcomes.

There is an established association between red blood cell (RBC) transfusion and increased mortality and morbidity in cardiac surgery; however, there is little data demonstrating the influence of blood transfusion while awaiting lung transplantation. Therefore, our study compared the impact of pretransplant RBC transfusion on patient survival and post-transplantation adverse events. Adult lung transplant patient data were extracted retrospectively using the United Network for Organ Sharing thoracic database. Patients were stratified into two groups based on pretransplant transfusion status. In total, 28,217 patients were analyzed in our study (transfused: n = 1,415 and not transfused: n = 26,802). There was an increasing trend in pretransplant transfusion rates from 2006 to 2020. Transfused patients had a higher incidence of adverse events post-transplantation, including dialysis, stroke, and acute organ rejection before discharge. Multivariable survival analysis found an increased mortality risk in patients who required pretransplant transfusion(s) compared to those who did not have a transfusion (hazard ratio [HR]: 1.27; 95% confidence interval [CI]: 1.17-1.41; p < 0.001). There was no significant difference in bronchiolitis obliterans syndrome development between groups (HR: 0.92; 95% CI: 0.82-1.04; p = 0.185). To conclude, our study provides data to suggest that RBC transfusion(s) before lung transplantation are associated with increased patient morbidity and mortality, but have no association with chronic graft rejection development.

Adequacy of Size Matching With Predicted Heart Mass Ratio in Diverse Types of Cardiomyopathies.

Predicted heart mass ratio (PHMr) has been proposed as an optimal size metric in the selection of a donor heart for transplant; however, it is not known if the same size matching criteria pertains uniformly to all types of cardiomyopathies. Heart transplant recipients in the United Network for Organ Sharing registry database were categorized into 6 groups based on the type of cardiomyopathy, dilated, coronary artery disease, hypertrophic, restrictive, valvular and adult congenital heart disease. Patients in each group of etiology were stratified based on the PHMr into 5 groups: severely undersized <0.86, moderately undersized 0.86 to 0.94, matched 0.95 to 1.04, moderately oversized 1.05 to 1.24, and severely oversized >1.25. The survival and cause of death of patients in each etiology group were reviewed. The United Network for Organ Sharing registry database from January 1987 to July 2021 included 53,573 patients who received a heart transplant. Compared with patients with size matched hearts, recipients with dilated (hazard ratio 1.17, p = 0.001) and valvular (hazard ratio 1.79, p = 0.032) cardiomyopathy who had an undersized heart with PHMr <0.86 had decreased survival. In addition, the survival of patients with hypertrophic or restrictive cardiomyopathy and adult congenital heart disease was not affected by size matching based on the PHMr (0.601 and 0.079, respectively, p = 0.873). In conclusion, our analysis suggests that the size matching criteria based on PHMr may not be uniform to all patients across various etiologies of cardiomyopathy. Therefore, the data can be used to increase the acceptance rate of donor hearts, particularly, for patients with hypertrophic, restrictive cardiomyopathy and congenital heart disease in which size matching is less significant for survival outcome.

Increased-risk versus standard-risk donation in lung transplantation: A United Network of Organ Sharing analysis.

OBJECTIVES: Donors with characteristics that increase risk of hepatitis B virus, hepatitis C virus, and HIV transmission are deemed increased-risk donors (IRDs) per Public Health Service guidelines. Compared with organs from standard-risk donors (SRDs), IRD organs are more frequently declined. We sought to investigate the outcomes of IRD lung transplant recipients following the 2013 guideline change. METHODS: We retrospectively identified lung transplant recipients using the United Network of Organ Sharing registry (February 2014 to March 2020). Patients were divided into 2 cohorts, based on Centers for Disease Control and Prevention risk status of the donor: SRD or IRD. Demographics and clinical parameters were compared across groups. Survival was compared using Kaplan-Meier curves and log-rank tests. Cox proportional hazard model was performed to identify variables associated with survival outcome. RESULTS: We identified 13,205 lung transplant recipients, 9963 who received allografts from SRDs and 3242 who received allografts from IRDs. In both groups, most donors were White, male, and <30 years old. IRDs demonstrated greater rates of heavy alcohol, cigarette, and cocaine use. SRDs had greater rates of cancer, hypertension, previous myocardial infarction, and diabetes. Survival analysis demonstrated no significant difference in 90-day, 1-year, 3-year, or 5-year survival outcome between SRD and IRD recipients (P = .34, P = .67, P = .40, P = .52, respectively). Cox regression demonstrated that double-lung transplants were associated with 13% decreased mortality risk compared with single-lung (P = .0009). CONCLUSIONS: IRD and SRD recipients demonstrated equivalent survival outcomes. Our study suggests that IRDs offer a safe approach to expand the donor pool and increase availability of lungs for transplantation.

Lung transplant survival with past and concomitant cardiac revascularization.

BACKGROUND: Coronary artery disease is common among lung transplant (LTx) candidates and has historically been viewed as a contraindication to the procedure. Survival outcomes of lung transplant recipients with concomitant coronary artery disease who had prior or perioperative revascularization remain a topic of conversation. METHODS: A retrospective analysis of all single and double lung transplant patients from Feb, 2012 to Aug, 2021 at a single center was performed (n = 880). Patients were split into 4 groups: (1) those who received a preoperative percutaneous coronary intervention, (2) those who received preoperative coronary artery bypass grafting, (3) those who received coronary artery bypass grafting during transplantation, and (4) those who had lung transplantation without revascularization. Groups were compared for demographics, surgical procedure, and survival outcomes using STATA Inc. A p value< 0.05 was considered significant. RESULTS: Most patients receiving LTx were male and white. Pump type (p = 0.810), total ischemic time (p = 0.994), warm ischemic time (p = 0.479), length of stay (p = 0.751), and lung allocation score (p = 0.332) were not significantly different between the four groups. The no revascularization group was younger than the other groups (p<0.01). The diagnosis of Idiopathic Pulmonary Fibrosis was predominant in all groups except the no revascularization group. The pre-coronary artery bypass grafting group had a higher portion of single LTx procedures (p = 0.014). Kaplan-Meier analysis showed no significantly different survival rates after post-LTx between the groups (p = 0.471). Cox Regression analysis showed diagnosis significantly impacted survival rates (p 0.009). CONCLUSIONS: Preoperative or intraoperative revascularization did not affect survival outcomes in lung transplant patients. Selected patients with coronary artery disease may benefit when intervened during lung transplant procedures.

Cerebral protection strategies for type A aortic dissection repair.

Importance: Techniques to preserve neurological function during type A aortic dissection repairs have been broadly discussed in the literature and heavily debated. Despite the effectiveness of various approaches, a consensus lacks on how to maintain optimal cerebral temperature during surgery. This review examines the three predominant cerebral protection strategies in aortic arch reconstructions: straight deep hypothermic circulatory arrest (sDHCA), retrograde cerebral perfusion (RCP), and antegrade cerebral perfusion (ACP). Observations: The signature characteristics of sDHCA, RCP, and ACP are similar-hypothermia, with or without cerebral perfusion. Employing cerebral perfusion techniques may prolong operative times, while ACP permits operation at higher body temperatures, albeit with restricted operative durations. Conclusion: For type A dissection arch reconstructions, sDHCA, RCP, and ACP can be successfully implemented. Factors such as operative times and individual patient conditions should be considered when choosing a cerebral protection strategy.

Two Staged Single Lung Transplants in the Current Era: A United Network for Organ Sharing Study.

BACKGROUND: We hypothesized that outcomes after 2 staged, contralateral single lung transplantation procedures (SSLTs) may be equivalent to those of double lung transplantation (DLT) by capitalizing on the known long-term survival advantages of DLT. METHODS: Using the United Network for Organ Sharing data set (1987-2018), the largest national data set available, the outcomes of 278 SSLTs were retrospectively analyzed and compared with the outcomes of 21,121 standard DLTs. RESULTS: During SSLT, the median interval between the 2 transplants was 960 days, and the indication for the second transplant was most often chronic lung allograft dysfunction (n = 148; 53.2%) or the same disease that necessitated the first transplant (n = 81; 29.1%). The patients who underwent SSLT were significantly older and had a higher baseline creatinine level than the patients who underwent DLT. Most posttransplantation short-term outcomes were equivalent between the second stage of SSLT and DLT, but renal insufficiency requiring hemodialysis was notably higher after SSLT. There were no differences in long-term survival. In multivariate analysis, baseline creatinine, O2 support at rest, ventilator support at the time of the second transplantation, and posttransplantation renal insufficiency requiring dialysis were independent predictors of 1-year mortality after SSLT. CONCLUSIONS: Over a study period of 30 years, long-term survival after SSLT was comparable with survival after DLT. With further analysis of individual risk profiles, including the contributions of preoperative renal function and functional status, SSLT can be a valuable option for patients who would have undergone single lung transplantation to reap the long-term benefits of a second transplant.

Lung Transplantation for COVID-19 Pulmonary Sequelae.

BACKGROUND: The role of lung transplantation for coronavirus disease 2019 (COVID-19)-related lung failure is evolving as the pandemic persists. METHODS: From January 2021 to April 2022, 20 patients (median age 62 y; range 31-77) underwent lung transplantation for COVID-related lung failure at our institution. We reviewed their clinical and intraoperative characteristics and early outcomes including postoperative complications. RESULTS: Eleven patients (55%) had chronic lung disease when they contracted COVID-19. All 20 patients required hospitalization for antivirus treatment. Median lung allocation score was 74.7 (33.1-94.0). Thirteen patients (65%) underwent single-lung transplants, and 7 patients (35%) underwent double-lung transplants. Concomitant coronary artery bypass graft surgery was performed in 2 (10%) patients because of severe coronary artery disease. Postoperatively, venovenous extracorporeal membrane oxygenation was needed in 3 patients (15%) because of severe primary graft dysfunction; all were eventually weaned. Ten patients (50%) experienced deep venous thrombosis, and 1 eventually developed a major pulmonary embolus. The median intensive care unit stay and hospital stays were 6.5 d (3-44) and 18 d (7-77), respectively. During a median follow-up of 201 d (47-418), we experienced 1 late mortality due to COVID-19-related myocarditis. Among the 13 patients with single-lung transplant, 5 demonstrated improvement in their native lungs. CONCLUSIONS: Lung transplantation yielded favorable early outcomes in a heterogeneous patient cohort that included older patients, obese patients, and patients with coronary artery disease or preexisting chronic lung disease. Our data also shed light on the transforming role of lung transplantation for the pulmonary sequelae of a complex multisystem COVID-19 disorder.