Distinctive In Vitro Phenotypes in iPSC-Derived Neurons From Patients With Gain- and Loss-of-Function SCN2A Developmental and Epileptic Encephalopathy.

SCN2A encodes NaV1.2, an excitatory neuron voltage-gated sodium channel and a major monogenic cause of neurodevelopmental disorders, including developmental and epileptic encephalopathies (DEE) and autism. Clinical presentation and pharmocosensitivity vary with the nature of SCN2A variant dysfunction and can be divided into gain-of-function (GoF) cases with pre- or peri-natal seizures and loss-of-function (LoF) patients typically having infantile spasms after 6 months of age. We established and assessed patient induced pluripotent stem cell (iPSC) - derived neuronal models for two recurrent SCN2A DEE variants with GoF R1882Q and LoF R853Q associated with early- and late-onset DEE, respectively. Two male patient-derived iPSC isogenic pairs were differentiated using Neurogenin-2 overexpression yielding populations of cortical-like glutamatergic neurons. Functional properties were assessed using patch clamp and multielectrode array recordings and transcriptomic profiles obtained with total mRNA sequencing after 2-4 weeks in culture. At 3 weeks of differentiation, increased neuronal activity at cellular and network levels was observed for R1882Q iPSC-derived neurons. In contrast, R853Q neurons showed only subtle changes in excitability after 4 weeks and an overall reduced network activity after 7 weeks in vitro. Consistent with the reported efficacy in some GoF SCN2A patients, phenytoin (sodium channel blocker) reduced the excitability of neurons to the control levels in R1882Q neuronal cultures. Transcriptomic alterations in neurons were detected for each variant and convergent pathways suggested potential shared mechanisms underlying SCN2A DEE. In summary, patient iPSC-derived neuronal models of SCN2A GoF and LoF pathogenic variants causing DEE show specific functional and transcriptomic in vitro phenotypes.

Carbogen-Induced Respiratory Acidosis Blocks Experimental Seizures by a Direct and Specific Inhibition of NaV1.2 Channels in the Axon Initial Segment of Pyramidal Neurons.

Brain pH is a critical factor for determining neuronal activity, with alkalosis increasing and acidosis reducing excitability. Acid shifts in brain pH through the breathing of carbogen (5% CO2/95% O2) reduces seizure susceptibility in animal models and patients. The molecular mechanisms underlying this seizure protection remain to be fully elucidated. Here, we demonstrate that male and female mice exposed to carbogen are fully protected from thermogenic-triggered seizures. Whole-cell patch-clamp recordings revealed that acid shifts in extracellular pH (pHo) significantly reduce action potential firing in CA1 pyramidal neurons but did not alter firing in hippocampal inhibitory interneurons. In real-time dynamic clamp experiments, acidification reduced simulated action potential firing generated in hybrid model neurons expressing the excitatory neuron predominant NaV1.2 channel. Conversely, acidification had no effect on action potential firing in hybrid model neurons expressing the interneuron predominant NaV1.1 channel. Furthermore, knockdown of Scn2a mRNA in vivo using antisense oligonucleotides reduced the protective effects of carbogen on seizure susceptibility. Both carbogen-mediated seizure protection and the reduction in CA1 pyramidal neuron action potential firing by low pHo were maintained in an Asic1a knock-out mouse ruling out this acid-sensing channel as the underlying molecular target. These data indicate that the acid-mediated reduction in excitatory neuron firing is mediated, at least in part, through the inhibition of NaV1.2 channels, whereas inhibitory neuron firing is unaffected. This reduction in pyramidal neuron excitability is the likely basis of seizure suppression caused by carbogen-mediated acidification.SIGNIFICANCE STATEMENT Brain pH has long been known to modulate neuronal excitability. Here, we confirm that brain acidification reduces seizure susceptibility in a mouse model of thermogenic seizures. Extracellular acidification reduced excitatory pyramidal neuron firing while having no effect on interneuron firing. Acidification also reduced dynamic clamp firing in cells expressing the NaV1.2 channel but not in cells expressing NaV1.1 channels. In vivo knockdown of Scn2a mRNA reduced seizure protection of acidification. In contrast, acid-mediated seizure protection was maintained in the Asic1a knock-out mouse. These data suggest NaV1.2 channel as an important target for acid-mediated seizure protection. Our results have implications on how natural variations in pH can modulate neuronal excitability and highlight potential antiseizure drug development strategies based on the NaV1.2 channel.

Retinal Dysfunction in a Mouse Model of HCN1 Genetic Epilepsy.

Pathogenic variants in HCN1 are associated with a range of epilepsy syndromes including a developmental and epileptic encephalopathy. The recurrent de novo HCN1 pathogenic variant (M305L) results in a cation leak, allowing the flux of excitatory ions at potentials where the wild-type channels are closed. The Hcn1M294L mouse recapitulates patient seizure and behavioral phenotypes. As HCN1 channels are highly expressed in rod and cone photoreceptor inner segments, where they shape the light response, mutated channels are likely to impact visual function. Electroretinogram (ERG) recordings from male and female mice Hcn1M294L mice revealed a significant decrease in the photoreceptor sensitivity to light, as well as attenuated bipolar cell (P2) and retinal ganglion cell responses. Hcn1M294L mice also showed attenuated ERG responses to flickering lights. ERG abnormalities are consistent with the response recorded from a single female human subject. There was no impact of the variant on the structure or expression of the Hcn1 protein in the retina. In silico modeling of photoreceptors revealed that the mutated HCN1 channel dramatically reduced light-induced hyperpolarization, resulting in more Ca2+ flux during the response when compared with the wild-type situation. We propose that the light-induced change in glutamate release from photoreceptors during a stimulus will be diminished, significantly blunting the dynamic range of this response. Our data highlight the importance of HCN1 channels to retinal function and suggest that patients with HCN1 pathogenic variants are likely to have a dramatically reduced sensitivity to light and a limited ability to process temporal information.SIGNIFICANCE STATEMENT Pathogenic variants in HCN1 are emerging as an important cause of catastrophic epilepsy. HCN1 channels are ubiquitously expressed throughout the body, including the retina. Electroretinogram recordings from a mouse model of HCN1 genetic epilepsy showed a marked decrease in the photoreceptor sensitivity to light and a reduced ability to respond to high rates of light flicker. No morphologic deficits were noted. Simulation data suggest that the mutated HCN1 channel blunts light-induced hyperpolarization and consequently limits the dynamic range of this response. Our results provide insights into the role HCN1 channels play in retinal function as well as highlighting the need to consider retinal dysfunction in disease caused by HCN1 variants. The characteristic changes in the electroretinogram open the possibility of using this tool as a biomarker for this HCN1 epilepsy variant and to facilitate development of treatments.

Improved Cardiac Function in Postischemic Rats Using an Optimized Cardiac Reprogramming Cocktail Delivered in a Single Novel Adeno-Associated Virus.

BACKGROUND: Cardiac reprogramming is a technique to directly convert nonmyocytes into myocardial cells using genes or small molecules. This intervention provides functional benefit to the rodent heart when delivered at the time of myocardial infarction or activated transgenically up to 4 weeks after myocardial infarction. Yet, several hurdles have prevented the advancement of cardiac reprogramming for clinical use. METHODS: Through a combination of screening and rational design, we identified a cardiac reprogramming cocktail that can be encoded in a single adeno-associated virus. We also created a novel adeno-associated virus capsid that can transduce cardiac fibroblasts more efficiently than available parental serotypes by mutating posttranslationally modified capsid residues. Because a constitutive promoter was needed to drive high expression of these cell fate-altering reprogramming factors, we included binding sites to a cardiomyocyte-restricted microRNA within the 3' untranslated region of the expression cassette that limits expression to nonmyocytes. After optimizing this expression cassette to reprogram human cardiac fibroblasts into induced cardiomyocyte-like cells in vitro, we also tested the ability of this capsid/cassette combination to confer functional benefit in acute mouse myocardial infarction and chronic rat myocardial infarction models. RESULTS: We demonstrated sustained, dose-dependent improvement in cardiac function when treating a rat model 2 weeks after myocardial infarction, showing that cardiac reprogramming, when delivered in a single, clinically relevant adeno-associated virus vector, can support functional improvement in the postremodeled heart. This benefit was not observed with GFP (green fluorescent protein) or a hepatocyte reprogramming cocktail and was achieved even in the presence of immunosuppression, supporting myocyte formation as the underlying mechanism. CONCLUSIONS: Collectively, these results advance the application of cardiac reprogramming gene therapy as a viable therapeutic approach to treat chronic heart failure resulting from ischemic injury.

Preface: Special issue: "Ion channels and genetic epilepsy".

This preface introduces the Journal of Neurochemistry Special Issue on Advances in Epilepsy Research. Epilepsy is a devastating disease characterized by recurrent seizures. Despite the addition of numerous therapeutics over the last few decades epilepsy patients resistant to standard of care treatments remains stubbornly high. This highlights a clear unmet clinical need and the importance of new research into this disease. One major advance over the last two decades has been the recognition that genetic factors play a significant role in the underlying pathogenesis of epilepsy. Much of our insights into the pathogenic mechanisms underlying genetic epilepsy has come from research into genes that encode ion channels. In this issue, there are up-to-date reviews discussing epilepsy caused by variation in HCN channels, voltage-dependent sodium channels, voltage-dependent calcium channels, and GABAA receptors. The reviews highlight our understanding of the genotype-phenotype relationships and the identification of precision medicine approaches. Complimenting this is a review on metabolic aspects modulating ion channels in genetic disease. This issue also has fundamental research manuscripts investigating how currently approved drugs may rescue NMDA receptor dysfunction and how in vitro neuron cultures can be used to probe network scale deficits and drug impacts in SCN2A disease. Other primary data manuscripts include those focusing on metabolic therapies, gut microbiota, and new in vivo screening tools for identifying novel anti-seizure drugs. Collectively, manuscripts published as part of this edition highlight recent research gains, especially in our understanding of genetic causes of epilepsy involving ion channels.

Variant-specific in vitro neuronal network phenotypes and drug sensitivity in SCN2A developmental and epileptic encephalopathy.

De novo variants in the NaV1.2 voltage-gated sodium channel gene SCN2A are among the major causes of developmental and epileptic encephalopathies (DEE). Based on their biophysical impact on channel conductance and gating, SCN2A DEE variants can be classified into gain-of-function (GoF) or loss-of-function (LoF). Clinical and functional data have linked early seizure onset DEE to the GoF SCN2A variants, whereas late seizure onset DEE is associated with the loss of SCN2A function. This study aims to assess the impact of GoF and LoF SCN2A variants on cultured neuronal network activity and explore their modulation by selected antiseizure medications (ASM). To this end, primary cortical cultures were generated from two knock-in mouse lines carrying variants corresponding to human GoF SCN2A p.R1882Q and LoF p.R853Q DEE variant. In vitro neuronal network activity and responses to ASM were analyzed using multielectrode array (MEA) between 2 and 4 weeks in culture. The SCN2A p.R1882Q neuronal cultures showed significantly greater mean firing and burst firing. Their network synchronicity was also higher. In contrast, the SCN2A p.R853Q cultures showed lower mean firing rate, and burst firing events were less frequent. The network synchronicity was also lower. Phenytoin and levetiracetam reduced the excitability of GoF cultures, while retigabine showed differential and potentially beneficial effects on cultures with both GoF and LoF variants. We conclude that in vitro neuronal networks harboring SCN2A GoF or LoF DEE variants present with distinctive phenotypes and responses to ASM.

Slc35a2 mosaic knockout impacts cortical development, dendritic arborisation, and neuronal firing.

Mild malformation of cortical development with oligodendroglial hyperplasia in epilepsy (MOGHE) is an important cause of drug-resistant epilepsy. A significant subset of individuals diagnosed with MOGHE display somatic mosaicism for loss-of-function variants in SLC35A2, which encodes the UDP-galactose transporter. We developed a mouse model to investigate how disruption of this transporter leads to a malformation of cortical development. We used in utero electroporation and CRISPR/Cas9 to knockout Slc35a2 in a subset of layer 2/3 cortical neuronal progenitors in the developing brains of male and female fetal mice to model mosaic expression. Mosaic Slc35a2 knockout was verified through next-generation sequencing and immunohistochemistry of GFP-labelled transfected cells. Histology of brain tissue in mosaic Slc35a2 knockout mice revealed the presence of upper layer-derived cortical neurons in the white matter. Reconstruction of single filled neurons identified altered dendritic arborisation with Slc35a2 knockout neurons having increased complexity. Whole-cell electrophysiological recordings revealed that Slc35a2 knockout neurons display reduced action potential firing, increased afterhyperpolarisation duration and reduced burst-firing when compared with control neurons. Mosaic Slc35a2 knockout mice also exhibited significantly increased epileptiform spiking and increased locomotor activity. We successfully generated a mouse model of mosaic Slc35a2 deficiency, which recapitulates features of the human phenotype, including impaired neuronal migration. We show that knockout in layer 2/3 cortical neuron progenitors is sufficient to disrupt neuronal excitability, increase epileptiform activity and cause hyperactivity in mosaic mice. Our mouse model provides an opportunity to further investigate the disease mechanisms that contribute to MOGHE and facilitate the development of precision therapies.

Transcriptional network analysis of peripheral blood leukocyte subsets in multiple sclerosis identifies a pathogenic role for a cytotoxicity-associated gene network in myeloid cells.

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system affecting predominantly adults. It is a complex disease associated with both environmental and genetic risk factors. Although over 230 risk single-nucleotide polymorphisms have been associated with MS, all are common human variants. The mechanisms by which they increase the risk of MS, however, remain elusive. We hypothesized that a complex genetic phenotype such as MS could be driven by coordinated expression of genes controlled by transcriptional regulatory networks. We, therefore, constructed a gene coexpression network from microarray expression analyses of five purified peripheral blood leukocyte subsets of 76 patients with relapsing remitting MS and 104 healthy controls. These analyses identified a major network (or module) of expressed genes associated with MS that play key roles in cell-mediated cytotoxicity which was downregulated in monocytes of patients with MS. Manipulation of the module gene expression was achieved in vitro through small interfering RNA gene knockdown of identified drivers. In a mouse model, network gene knockdown modulated the autoimmune inflammatory MS model disease-experimental autoimmune encephalomyelitis. This research implicates a cytotoxicity-associated gene network in myeloid cells in the pathogenesis of MS.

Short- and long-term impact of aspirin cessation in older adults: a target trial emulation.

BACKGROUND: The net benefit of aspirin cessation in older adults remains uncertain. This study aimed to use observational data to emulate a randomized trial of aspirin cessation versus continuation in older adults without cardiovascular disease (CVD). METHODS: Post hoc analysis using a target trial emulation framework applied to the immediate post-trial period (2017-2021) of a study of low-dose aspirin initiation in adults aged ≥ 70 years (ASPREE; NCT01038583). Participants from Australia and the USA were included if they were free of CVD at the start of the post-trial intervention period (time zero, T0) and had been taking open-label or randomized aspirin immediately before T0. The two groups in the target trial were as follows: aspirin cessation (participants who were taking randomized aspirin immediately before T0; assumed to have stopped at T0 as instructed) versus aspirin continuation (participants on open-label aspirin at T0 regardless of their randomized treatment; assumed to have continued at T0). The outcomes after T0 were incident CVD, major adverse cardiovascular events (MACE), all-cause mortality, and major bleeding during 3, 6, and 12 months (short-term) and 48 months (long-term) follow-up. Hazard ratios (HRs) comparing aspirin cessation to continuation were estimated from propensity-score (PS) adjusted Cox proportional-hazards regression models. RESULTS: We included 6103 CVD-free participants (cessation: 5427, continuation: 676). Over both short- and long-term follow-up, aspirin cessation versus continuation was not associated with elevated risk of CVD, MACE, and all-cause mortality (HRs, at 3 and 48 months respectively, were 1.23 and 0.73 for CVD, 1.11 and 0.84 for MACE, and 0.23 and 0.79 for all-cause mortality, p > 0.05), but cessation had a reduced risk of incident major bleeding events (HRs at 3 and 48 months, 0.16 and 0.63, p < 0.05). Similar findings were seen for all outcomes at 6 and 12 months, except for a lowered risk of all-cause mortality in the cessation group at 12 months. CONCLUSIONS: Our findings suggest that deprescribing prophylactic aspirin might be safe in healthy older adults with no known CVD.

WONOEP appraisal: Modeling early onset epilepsies.

Epilepsy has a peak incidence during the neonatal to early childhood period. These early onset epilepsies may be severe conditions frequently associated with comorbidities such as developmental deficits and intellectual disability and, in a significant percentage of patients, may be medication-resistant. The use of adult rodent models in the exploration of mechanisms and treatments for early life epilepsies is challenging, as it ignores significant age-specific developmental differences. More recently, models developed in immature animals, such as rodent pups, or in three-dimensional organoids may more closely model aspects of the immature brain and could result in more translatable findings. Although models are not perfect, they may offer a more controlled screening platform in studies of mechanisms and treatments, which cannot be done in pediatric patient cohorts. On the other hand, more simplified models with higher throughput capacities are required to deal with the large number of epilepsy candidate genes and the need for new treatment options. Therefore, a combination of different modeling approaches will be beneficial in addressing the unmet needs of pediatric epilepsy patients. In this review, we summarize the discussions on this topic that occurred during the XVI Workshop on Neurobiology of Epilepsy, organized in 2022 by the Neurobiology Commission of the International League Against Epilepsy. We provide an overview of selected models of early onset epilepsies, discussing their advantages and disadvantages. Heterologous expression models provide initial functional insights, and zebrafish, rodent models, and brain organoids present increasingly complex platforms for modeling and validating epilepsy-related phenomena. Together, these models offer valuable insights into early onset epilepsies and accelerate hypothesis generation and therapy discovery.

Clinical outcomes and coronary artery lesion characteristics of young patients with ST elevation myocardial infarction and no standard modifiable risk factors.

BACKGROUND: Among ST-elevation myocardial infarction (STEMI) patients, those with no standard modifiable risk factors (SMuRFs: hypertension, diabetes mellitus, hypercholesterolemia, and smoking) have higher 30-day mortality than those with SMuRFs. Differences in coronary lesion characteristics remain unclear. METHODS: Data from STEMI patients aged ≤60 years from the Asia Pacific Evaluation of Cardiovascular Therapies Network (Australia, Hong Kong, Malaysia, Singapore, and Vietnam) was retrospectively analysed. Exclusion criteria included incomplete SMuRF data, prior myocardial infarction, or prior coronary revascularisation. Lesion type was defined using the American College of Cardiology criteria. Major adverse cardiovascular events (MACE) were defined as peri-procedural myocardial infarction, emergency coronary artery bypass surgery, cerebrovascular event, or mortality. Multiple logistic regressions were used. RESULTS: Of 4404 patients, 767 (17.4%) were SMuRFless. SMuRFless patients were more frequently younger (median age 51 vs. 53 years; p < 0.001), female (22.6% vs. 15.5%; p < 0.001), thrombolysed (20.1% vs. 12.5%; p < 0.001), and in cardiogenic shock (11.2% vs. 8.6%; p = 0.020). SMuRFless patients had significantly higher in-hospital MACE (7.2% vs. 4.3%; adjusted odds ratio [aOR] 2.25; 95% confidence interval [CI] 1.24-4.08; p = 0.008) but 1-year mortality was not significantly different (3.6% vs. 5.7%, aOR 0.58; 95% CI 0.06-6.12; p = 0.549). Compared with patients with SMuRFs (4918 lesions), the SMuRFless (940 lesions) had fewer type B2/C lesions (60.8% vs. 65.6%; p = 0.020) and fewer lesions ≥20 mm (51.1% vs. 57.1%; p = 0.002) but more procedural complications (5.1% vs. 2.7%; p < 0.001). CONCLUSIONS: Among young STEMI patients, the SMuRFless have shorter and less complex lesions, but worse procedural and short-term MACE outcomes.

Immediate and delayed flap reconstruction have equivalent outcomes and associated costs following soft tissue sarcoma surgery.

BACKGROUND AND OBJECTIVES: Surgical treatment of soft tissue sarcoma (STS) involves wide resection of the tumor, which can necessitate soft tissue reconstruction with local or free tissue flaps. This retrospective study compares cost, surgical and oncologic outcomes between patients undergoing reconstruction with immediate versus delayed flap coverage following STS resection. METHODS: Thirty-four patients who underwent planned flap reconstruction following resection of primary STS were identified retrospectively. Twenty-four (71%) received immediate reconstruction during the index surgery and 10 (29%) underwent planned delayed reconstruction. Preoperative patient-specific metrics, tumor characteristics, and surgical and patient outcomes were collected. Total hospital charges associated with every encounter during the perioperative period were obtained. RESULTS: Patient demographics, comorbidities, tumor metrics, and surgical characteristics were equivalent between groups. Postoperative wound complications, reoperations, readmissions, and disease-specific survival did not differ between cohorts. Costs associated with each reconstruction strategy were equivalent on bivariate and multivariate testing, when accounting for operating room time, hospital length of stay, and reoperation rate. CONCLUSIONS: Our study identifies no significant difference in patient outcome measures or cost between planned immediate and delayed flap reconstruction following STS resection. These results support the implementation of either treatment strategy in keeping with patient-centered, multidisciplinary care principles.

Stuttering associated with a pathogenic variant in the chaperone protein cyclophilin 40.

Stuttering is a common speech disorder that interrupts speech fluency and tends to cluster in families. Typically, stuttering is characterized by speech sounds, words or syllables which may be repeated or prolonged and speech that may be further interrupted by hesitations or 'blocks'. Rare variants in a small number of genes encoding lysosomal pathway proteins have been linked to stuttering. We studied a large four-generation family in which persistent stuttering was inherited in an autosomal dominant manner with disruption of the cortico-basal-ganglia-thalamo-cortical network found on imaging. Exome sequencing of three affected family members revealed the PPID c.808C>T (p.Pro270Ser) variant that segregated with stuttering in the family. We generated a Ppid p.Pro270Ser knock-in mouse model and performed ex vivo imaging to assess for brain changes. Diffusion-weighted MRI in the mouse revealed significant microstructural changes in the left corticospinal tract, as previously implicated in stuttering. Quantitative susceptibility mapping also detected changes in cortico-striatal-thalamo-cortical loop tissue composition, consistent with findings in affected family members. This is the first report to implicate a chaperone protein in the pathogenesis of stuttering. The humanized Ppid murine model recapitulates network findings observed in affected family members.

Multimorbidity impacts cardiovascular disease risk following percutaneous coronary intervention: latent class analysis of the Melbourne Interventional Group (MIG) registry.

BACKGROUND: Multimorbidity is strongly associated with disability or functional decline, poor quality of life and high consumption of health care services. This study aimed (1) To identify patterns of multimorbidity among patients undergoing first recorded percutaneous coronary intervention (PCI); (2) To explore the association between the identified patterns of multimorbidity on length of hospital stay, 30-day and 12- month risk of major adverse cardiac and cerebrovascular events (MACCE) after PCI. METHODS: A retrospective cohort study of the Melbourne Interventional Group (MIG) registry. This study included 14,025 participants who underwent their first PCI from 2005 to 2015 in Victoria, Australia. Based on a probabilistic modelling approach, Latent class analysis was adopted to classify clusters of people who shared similar combinations and magnitude of the comorbidity of interest. Logistic regression models were used to estimate odd ratios and 95% confidence interval (CI) for the 30-day and 12-month MACCE. RESULTS: More than two-thirds of patients had multimorbidity, with the most prevalent conditions being hypertension (59%) and dyslipidaemia (60%). Four distinctive multimorbidity clusters were identified each with significant associations for higher risk of 30-day and 12-month MACCE. The cluster B had the highest risk of 30-day MACCE event that was characterised by a high prevalence of reduced estimated glomerular filtration rate (92%), hypertension (73%) and reduced ejection fraction (EF) (57%). The cluster C, characterised by a high prevalence of hypertension (94%), dyslipidaemia (88%), reduced eGFR (87%), diabetes (73%) and reduced EF (65%) had the highest risk of 12-month MACCE and highest length of hospital stay. CONCLUSION: Hypertension and dyslipidaemia are prevalent in at least four in ten patients undergoing coronary angioplasty. This study showed that clusters of patients with multimorbidity had significantly different risk of 30-day and 12-month MACCE after PCI. This suggests the necessity for treatment approaches that are more personalised and customised to enhance patient outcomes and the quality of care delivered to patients in various comorbidity clusters. These results should be validated in a prospective cohort and to evaluate the potential impacts of these clusters on the prevention of MACCE after PCI.

Cardiovascular Disease Risk Scores and Incident Dementia and Cognitive Decline in Older Men and Women.

INTRODUCTION: Risk factors for cardiovascular disease (CVD) also increase the risk of dementia. However, whether commonly used CVD risk scores are associated with dementia risk in older adults who do not have a history of CVD, and potential gender differences in this association, remains unclear. The aim of this study was to determine whether CVD risk scores are prospectively associated with cognitive decline and dementia in initially healthy older men and women. METHODS: A total of19,114 participants from a prospective cohort of individuals aged 65+ years without known CVD or dementia were recruited. The atherosclerotic cardiovascular disease risk score (ASCVDRS), Systematic Coronary Risk Evaluation 2-Older Persons (SCORE2-OP), and the Framingham risk score (FRS) were calculated at baseline. Risk of dementia (according to DSM-IV criteria) and cognitive decline (defined as a >1.5 standard deviation decline in global cognition, episodic memory, psychomotor speed, or verbal fluency from the previous year) were assessed using hazard ratio. RESULTS: Over a median follow-up of 6.4 years, 850 individuals developed dementia and 4,352 cognitive decline. Men and women in the highest ASCVDRS tertile had a 41% (95% CI 1.08, 1.85) and 45% (1.11, 1.89) increased risk of dementia compared to the lowest tertile, respectively. Likewise, men and women in the highest SCORE2-OP tertile had a 64% (1.24, 2.16) and 60% (1.22, 2.11) increased risk of dementia compared to the lowest tertile, respectively. Findings were similar, but the risk was slightly lesser when examining risk of cognitive decline for both ASCVDRS and SCORE2-OP. However, FRS was only associated with the risk of cognitive decline among women (highest vs. lowest tertiles: 1.13 [1.01-1.26]). CONCLUSION: These findings suggest the utility of the ASCVDRS and SCORE2-OP in clinical practice, to not only assess future risk of CVD, but also as potential early indicators of cognitive impairment, even in relatively healthy older men and women.

Development and Validation of Scores to Predict Prolonged Mechanical Ventilation after Cardiac Surgery.

OBJECTIVES: To optimize the early prediction of prolonged postoperative mechanical ventilation after cardiac surgery (>24 hours postoperatively). DESIGN: The authors performed a retrospective analysis. SETTING: The Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) database was utilized. PARTICIPANTS: All patients included in the ANZSCTS database between January 2015 and December 2018 were analyzed. INTERVENTIONS: No interventions were performed in this observational study. MEASUREMENTS AND MAIN RESULTS: A previously developed model was modified to allow retrospective risk calculation and model assessment (Modified Hessels score). The database was split into development and validation sets. A new risk model was developed using forward and backward stepwise elimination (ANZ-PreVent score). The authors assessed 48,382 patients, of whom 5004 (10.3%) were ventilated mechanically for >24 hours post-operatively. The Modified Hessels score demonstrated good performance in this database, with a c-index of 0.78 (95% CI 0.77-0.78) and a Brier score of 0.08. The newly developed ANZ-PreVent score demonstrated better performance (validation cohort, n = 12,229), with a c-index of 0.84 (95% CI 0.83-0.85) (p < 0.0001) and a Brier score of 0.07. Both scores performed better than the severity of illness scores commonly used to predict outcomes in intensive care. CONCLUSIONS: The authors validated a modified version of an existing prediction score and developed the ANZ-PreVent score, with improved performance for identifying patients at risk of ventilation for >24 hours. The improved score can be used to identify high-risk patients for targeted interventions in future randomized controlled trials.

Bi-National Outcomes of Redo Surgical Aortic Valve Replacement in the Era of Valve-in-Valve Transcatheter Aortic Valve.

BACKGROUND: Implantation of bioprosthetic valves is more common as the population ages and there is a shift towards implanting bioprosthetic aortic valves in an increasingly younger surgical population. Bioprosthetic heart valve insertion, however, carries the long-term risk of valve failure through structural valve degeneration. Re-operative surgical aortic valve replacement has historically been the only definitive management option for patients with prosthetic valve dysfunction, however, data on the short- and long-term outcomes following re-operative surgery in Australia and New Zealand is limited. METHOD: Data on all patients who underwent redo aortic valve surgery, over a 20-year period (up to 2021) was obtained from the Australian and New Zealand Society of Cardiothoracic Surgery Registry. RESULTS: A total of 1,199 patients (770 males; 64.2% and 429 females; 35.8%) were included in the overall analysis. The 30-day mortality was 6.4% with operative urgency status the most important risk factor for peri-operative mortality. The long-term survival rate of 1,145 patients was 90.5% (95% confidence interval [CI] 88.8%-92.3%), 77% (95% CI 73.9%-80.2%) and 57.2% (95% CI 55.2%-62.8%) at 1-, 5- and 10-years post-procedure, respectively, with a median survival of 12.7 years. Pre-existing chronic kidney disease was strongly associated with poorer long-term survival. For patients under 70 years of age the 1-, 5- and 10-year survival rates were 92.9% (95% CI 90.9%-95.1%), 83.6% (95% CI 80.1%-87.3%) and 73.1% (95% CI 67.4%-79.3%), respectively. CONCLUSIONS: The results from this registry study indicate that in Australia and New Zealand, a repeat surgical aortic valve replacement can result in a relatively low mortality rate, serving as a reference point for medical procedures in these regions.

Comparison of Characteristics and Outcomes in Patients With Acute Decompensated Heart Failure Admitted Under General Medicine and Cardiology Units.

BACKGROUND: Acute decompensated heart failure (ADHF) is a leading cause of cardiovascular disease hospitalisations associated with significant morbidity and mortality. In hospitals, HF patients are typically managed by cardiology or physician teams, with differences in patient demographics and clinical outcomes. This study utilises contemporary HF registry data to compare patient characteristics and outcomes in those with ADHF admitted into General Medicine and Cardiology units. METHODS: The Victorian Cardiac Outcomes Registry was utilised to identify patients hospitalised with ADHF 30-day period in each of four consecutive years. We compared patient characteristics, pharmacological management and outpatient follow-up of patients admitted to General Medicine and Cardiology units. Primary outcome measures included in-hospital mortality, 30-day readmission, and 30-day mortality. RESULTS: Between 2014 and 2017, a total of 1,253 patients with ADHF admissions were registered, with 53% admitted in General Medicine units and 47% in Cardiology units. General Medicine patients were more likely to be older (82 vs 71 years; p<0.001), female (51% vs 34%; p<0.001), and have higher prevalence of comorbidities and preserved left ventricular function (p<0.001). There were no differences in primary outcome measures between General Medicine and Cardiology in terms of: in-hospital mortality (5.0% vs 3.9%; p=0.35), 30-day readmission (23.4% vs 23.6%; p=0.93), and 30-day mortality (10.0% vs 8.0%; p=0.21). CONCLUSIONS: Hospitalised patients with HF continue to have high mortality and rehospitalisation rates. The choice of treatment by General Medicine or Cardiology units, based on the particular medical profile and individual needs of the patients, provides equivalent outcomes.

Clinical Outcomes of Renal Transplant Recipients Undergoing Percutaneous Coronary Intervention.

BACKGROUND: Clinical outcomes of patients with renal transplant (RT) undergoing percutaneous coronary intervention (PCI) remain poorly elucidated. METHOD: Between 2014 and 2021, data were analysed for the following three groups of patients undergoing PCI enrolled in a multicentre Australian registry: (1) RT recipients (n=226), (2) patients on dialysis (n=992), and (3) chronic kidney disease (CKD) patients (estimated glomerular filtration rate [eGFR], 30‒60 mL/min per 1.73 m2) without previous RT (n=15,534). Primary outcome was 30-day major adverse cardiac and cerebrovascular events (MACCEs)-composite of mortality, myocardial infarction, stent thrombosis, target vessel revascularisation, and stroke. RESULTS: RT recipients were younger than dialysis and patients with CKD (61±10 vs 68±12 vs 78±8.2 years, p<0.001). Patients with RT less frequently had severe left ventricular dysfunction compared with dialysis and CKD groups (6.7% vs 14% and 8.5%); however more, often presented with acute coronary syndrome (58% vs 52% and 48%), especially STEMI (all p<0.001). Patients with RT and CKD had lower rates of 30-day MACCE (4.4% and 6.8% vs 11.6%, p<0.001) than the dialysis group. Three-year survival was similar between RT and CKD groups, however was lower in the dialysis group (80% and 83% vs 60%, p<0.001). After adjustment, dialysis was an independent predictor of 30-day MACCE (odds ratio [OR] 1.90, 95% confidence interval [CI] 1.44‒2.50, p<0.001), however RT was not (OR 0.91, CI 0.42‒1.96, p=0.802). Both RT (hazard ratio [HR] 2.07, CI 1.46‒2.95, p<0.001) and dialysis (HR 1.35, CI 1.02‒1.80, p=0.036) heightened the hazard of long-term mortality. CONCLUSIONS: RT recipients have more favourable clinical outcomes following PCI compared with patients on dialysis. However, despite having similar short-term outcomes to patients with CKD, the hazard of long-term mortality is significantly greater for RT recipients.

Prevalence and Predictors of Emergency Medical Service Use in Patients Undergoing Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction.

AIM: We aim to describe prevalence of Emergency Medical Service (EMS) use, investigate factors predictive of EMS use, and determine if EMS use predicts treatment delay and mortality in our ST-elevation myocardial infarction (STEMI) cohort. METHOD: We prospectively collected data on 5,602 patients presenting with STEMI for primary percutaneous coronary intervention (PCI) transported to PCI-capable hospitals in Victoria, Australia, from 2013-2018 who were entered into the Victorian Cardiac Outcomes Registry (VCOR). We linked this dataset to the Ambulance Victoria and National Death Index (NDI) datasets. We excluded late presentation, thrombolysed, and in-hospital STEMI, as well as patients presenting with cardiogenic shock and out-of-hospital cardiac arrest. RESULTS: In total, 74% of patients undergoing primary PCI for STEMI used EMS. Older age, female gender, higher socioeconomic status, and a history of prior ischaemic heart disease were independent predictors of using EMS. EMS use was associated with shorter adjusted door-to-balloon (53 vs 72 minutes, p<0.001) and symptom-to-balloon (183 vs 212 minutes, p<0.001) times. Mode of transport was not predictive of 30-day or 12-month mortality. CONCLUSIONS: EMS use in Victoria is relatively high compared with internationally reported data. EMS use reduces treatment delay. Predictors of EMS use in our cohort are consistent with those prevalent in prior literature. Understanding the patients who are less likely to use EMS might inform more targeted education campaigns in the future.