The Journal of Heart and Lung Transplantation

Background: Antibody-mediated rejection (AMR) after heart transplant (HT) is associated with increased risk of mortality and graft loss. Contemporary studies delineating AMR presentation, management, and response to treatment are lacking, especially for patients who do not have typical immunohistological evidence of rejection (biopsy-negative, BN-AMR). In this study, we sought to describe the prevalence and clinical course of BN-AMR compared to biopsy-positive (BP-AMR) patients in a multicenter HT population. Methods: We conducted a retrospective analysis of all adult HT recipients at 2 academic medical centers. AMR was further divided into BP-AMR and BN-AMR, depending on their endomyocardial biopsy findings. The primary outcome was death and secondary outcome was a composite of death, retransplant, and new International Society of Heart and Lung Transplant grade 2 or 3 coronary artery vasculopathy. Results: A total of 742 patients were included in this study. We found that AMR occurred in 10% of HT recipients and was associated with worse overall survival compared to those with only cellular rejection or no rejection. BN-AMR accounted for 33% of AMR cases. Compared to BP-AMR, BN-AMR was diagnosed later, less aggressively treated, and associated with high morbidity and mortality. The long-term outcomes between BP-AMR and BN-AMR were similarly poor, with 5-year mortality approaching 50% after diagnosis. Conclusions: AMR after HT is associated with poor clinical outcomes and BN-AMR is common. Future studies should focus on incorporating novel tools for earlier detection of AMR and investigating AMR sub-phenotypes and optimal modes of treatment.

BackgroundWe aimed to identify data-driven FEV1 trajectory phenotypes post-chronic lung allograft dysfunction (CLAD), relate these phenotypes to patient factors and future graft loss, and develop a classification approach for prospective patients. MethodsWe studied adult first lung recipients with probable CLAD from two prospective multicenter cohorts: CTOT-20 (n=206) and LTOG (n=1418). FEV1 trajectories over the first nine months post-CLAD were characterized using joint latent class mixed models, jointly modelling time-to-graft loss to account for informative censoring. Models were fit independently in both cohorts and also only among LTOG bilateral recipients. A classification and regression tree (CART) model was derived in LTOG bilateral recipients and applied to CTOT-20 bilateral recipients. FindingsFour distinct early FEV1 trajectory classes were identified in CTOT-20, with large differences in nine-month graft loss (72{middle dot}3%, 31{middle dot}1%, 2{middle dot}2%, 0%). In LTOG, similar trajectory patterns were reproduced, with an additional class demonstrating early post-CLAD FEV1 improvement. Among bilateral recipients, trajectory classes showed a clear risk gradient, including a high-risk class with 100% graft loss and a low-risk class with no early graft loss. A CART model incorporating clinical and spirometric variables demonstrated good discrimination in LTOG bilateral recipients (multiclass AUC 0{middle dot}85) and consistent class assignment and trajectory patterns when applied to CTOT-20. InterpretationWe identified reproducible, clinically meaningful early post-CLAD FEV1 trajectory phenotypes with differential graft loss risk. These phenotypes and a pragmatic classification tool may support risk stratification, trial enrichment, and improved prognostication for patients and clinicians. FundingNational Institutes of Health, Cystic Fibrosis Foundation

Tricuspid regurgitation and pulmonary artery systolic pressure may contribute to post-operative morbidity and mortality in liver transplantation. Previous studies suggest that a high Model for End-Stage Liver Disease score may influence the relationship between tricuspid regurgitation and post-operative mortality. Adult patients undergoing liver transplantation workup between 2010 and 2023 were included in this retrospective observational cohort study. Patients with significant portopulmonary hypertension were excluded. Transthoracic echocardiograms were completed pre-transplant and patients were followed up for one year post-operatively. 1031 patients (median MELD score 17, IQR 12-23) underwent transthoracic echocardiography for liver transplantation workup, of whom 708 underwent successful transplantation. Mild or greater tricuspid regurgitation did not predict 1-year mortality in the overall population (HR 1.79 (95% CI 0.78-4.11), p=0.19). Among patients with MELD scores [≥]20, mild or greater tricuspid regurgitation was a significant predictor of 1-year mortality (7 (12.7%) vs 9 (3.8%), p=0.01) (HR 3.46 (1.30-10.32), p=0.02). Tricuspid regurgitation in patients with high MELD scores was associated with a trend towards an increased risk of 30-day major adverse cardiovascular events (9 (16.4)% vs 46 (8.1%), p=0.06), driven predominantly by rates of post-operative heart failure (12.7% vs 3.8%, HR 3.66 (95%CI 1.30-10.32), p=0.01). Elevated pulmonary artery systolic pressure was associated with prolonged hospital stay (30 days (14-46) vs 15 days (11-29), p=0.01). Our study confirms that mild or greater tricuspid regurgitation is a significant predictor of 1-year mortality in patients with high MELD scores undergoing liver transplantation. Tricuspid regurgitation severity should be considered during pre-liver transplantation risk stratification.

Background: Primary graft dysfunction (PGD) remains one of the leading causes of early mortality after pediatric heart transplant (HT). While neurodevelopmental impacts of congenital heart disease (CHD) are well-characterized, the effect of PGD on long-term neurodevelopmental outcomes in pediatric HT recipients remains unknown. We sought to determine the association between PGD and neurodevelopmental outcomes in this population. Methods: We performed a retrospective cohort study using the United Network for Organ Sharing (UNOS) database. All pediatric (age <18 years) isolated heart transplant recipients from 2010-2025 were included. The most recent pre- and post-transplant neurodevelopmental outcomes including cognitive delay, motor development, academic progress, and function status (stratified by age) were compared between PGD (n=434) and non- PGD groups (n=6956). Results: PGD patients had significantly worse pre-transplant functional status and motor development. Post-transplant, PGD was associated with worse motor development (18.8% vs. 13.0% definite motor delay; p=0.01) and functional status in younger children (39.5% vs. 57.8% able to keep up with peers; p<0.001). Post-transplant stroke occurred 3.5 times more frequently in PGD patients (11.5% vs. 3.3%; p<0.001). Cognitive development (p=0.94) and academic progress (p=0.096) did not differ significantly. Thirty-day (7.8% vs. 1.9%) and 1-year mortality (20.3% vs. 6.4%) were significantly higher in PGD patients (both p<0.001). Conclusions: This is the first study to characterize neurodevelopmental outcomes in pediatric patients undergoing HT with PGD. PGD is associated with significantly worse motor development and functional status independent of pre-transplant baseline. There is a 3.5-fold higher stroke rate providing a plausible neurological mechanism. The findings support targeted developmental surveillance recommendations and early intervention for this high-risk population.

Donor derived cell free DNA (ddcfDNA) is increasingly used for post transplantation non invasive surveillance; however, its clinical interpretation remains inconsistent, with widely ranging thresholds and is typically applied as a single binary cutoff in literature. The optimal decision framework for rule out and rule in decisions, and whether a single threshold remains clinically meaningful, are currently uncertain. We performed a Bayesian hierarchical summary receiver operating characteristic (HSROC) meta analysis of 14 studies (1,763 patients) evaluating ddcfDNA against endomyocardial biopsy. To account for serial testing within individuals, we applied a cluster corrected design effect, reducing 6,103 observations to 2,518 effective tests. Threshold dependent sensitivity and specificity were modelled continuously. We compared a conventional single threshold approach (Youden index) with a data driven adaptive framework defining rule out and rule in thresholds. Clinical utility was evaluated using decision curve analysis across a range of rejection prevalences (10% to 30%), incorporating repeat testing strategies. The pooled area under the HSROC curve was 0.78 (95% CrI, 0.67 to 0.84). The Youden optimal threshold (0.20%) yielded balanced sensitivity (0.77) and specificity (0.77) but failed to support clinical objectives of diagnosis. An adaptive framework identified a rule out threshold of 0.16% (sensitivity 0.80) and a rule in threshold of 0.48% (specificity 0.90), defining a indeterminate / grey zone. Across all prevalence scenarios, ddcfDNA guided strategies provided positive net benefit compared with biopsy all and biopsy none approaches. A repeat if borderline strategy consistently achieved the highest net benefit, particularly in low and intermediate risk settings, by reducing false positive biopsies without materially compromising detection. A single threshold interpretation is not clinically adequate for post heart transplant surveillance. Our tri state, prevalence aware framework integrating rule out, indeterminate, and rule in zones with selective repeat testing, more accurately reflects biomarker behavior and improves clinical decision making. These findings support a shift away from binary thresholds toward dynamic, context dependent use of ddcfDNA in transplant surveillance.

Cardiogenic shock (CS) is associated with high short-term mortality and the use of temporary mechanical circulatory support (tMCS) devices, especially left-sided microaxial flow pumps (Impella, Abiomed), has increased in recent years. However, few studies have investigated tMCS's effect on right ventricular-pulmonary artery (RV-PA) hemodynamics and its impact on clinical outcomes. We retrospectively analyzed all adult patients implanted with Impella 5.5 at our institution with acute myocardial infarction or acute decompensated heart failure-induced CS between 2019 to 2023. We found that Impella 5.5 led to an early improvement in RV-PA hemodynamics, even in patients with poor baseline RV function. In addition, we found that RV function itself did not predict death, post-heart transplant right ventricular-primary graft dysfunction, or post-left ventricular assist device severe RV failure. However, an increase in right atrial:pulmonary capillary wedge pressure ratio (RA/PCWP) despite tMCS support was a powerful prognosticator. Our study sheds important insight into anticipated hemodynamic changes after Impella 5.5 placement, supports the use of early tMCS even in patients with marginal RV function in the setting of left heart disease, and highlights the importance of serial assessment of RA/PCWP as a key determinant of CS outcomes.

BackgroundPediatric dilated cardiomyopathy (DCM) is a rare, progressive heart disease with variable outcomes that range from recovery to heart transplantation. To date, there are no prognostic biomarkers for children with DCM. Identifying circulating biomarkers that are associated with clinical outcomes is critical for personalized management. MethodsmiRNAs were identified by RNA-seq, whereas proteins were identified by SomaScan(R). Machine learning methodologies were used to explore the predictive ability of circulating factors identified from serum samples collected at the time of presentation with acute heart failure. ResultsThirty patients experienced poor outcomes (cardiac transplantation, mechanical circulatory support, or death) and 19 patients recovered left ventricular function. Distinct miRNA and protein signatures differentiated outcomes groups. Top candidate proteins (COL2A1, CXCL12, and ADGRF5) and miRNAs (miR-874-3p, miR-335-3p, miR-323a-3p) demonstrated strong discriminatory performance within the study cohort (recovered vs poor outcomes; Area Under the Curve of 0.92). Ingenuity Pathway Analysis implicates cardiac remodeling, fibrosis, and inflammatory signaling as central pathways differentiating patient outcomes. ConclusionsCirculating miRNA and protein signatures at presentation identify a circulating molecular signature associated with divergent clinical trajectories in pediatric DCM. These findings support the potential utility of multi-omic biomarkers for early risk stratification and provide insight into mechanisms underlying divergent outcomes. CLINICAL PERSPECTIVEWhat Is New? O_LICirculating miRNA and protein profiles measured at presentation distinguish children with pediatric DCM who recover from those who progress to advanced heart failure. C_LIO_LIA combined multi-omic biomarker demonstrated strong discriminatory performance in this cohort (AUC 0.92). C_LIO_LIPathway analysis implicates extracellular matrix remodeling, fibrosis, and inflammatory signaling in children with adverse clinical trajectories. C_LI What Are the Clinical Implications? O_LISerum-based molecular biomarkers may enable earlier risk stratification in children presenting with dilated cardiomyopathy. C_LIO_LIMulti-omic integration may improve identification of pediatric patients at risk for transplantation, mechanical circulatory support, or death. C_LIO_LIThese findings support further validation of circulating biomarker panels to guide personalized management in this rare disease. C_LI RESEARCH PERSPECTIVEWhat New Question Does This Study Raise? O_LICan integrated circulating miRNA-protein signatures identify biologically distinct trajectories of recovery versus progression in children with dilated cardiomyopathy? C_LIO_LIDo circulating molecular profiles reflect underlying disease mechanisms that determine divergent clinical outcomes in pediatric DCM? C_LI What Question Should Be Addressed Next? O_LIDo the pathways identified by integrated miRNA-protein analysis (fibrosis, remodeling, and inflammation) play causal roles in determining recovery versus progression? C_LIO_LICan multi-omic biomarkers be incorporated into prospective studies to improve early risk stratification and guide clinical management? C_LI

Background: The importance of lactate trajectory during the first day of cardiogenic shock is increasingly recognized. We aimed to assess the association between admission-day lactate trajectory and in-hospital mortality, and to identify same-day interventions predictive of lactate clearance. Methods: We analyzed adult patients admitted with cardiogenic shock between October 2015 and June 2023, using the Vizient(R) Clinical Data Base. Early lactate clearance was defined as lactate <2.5 mmol/L by the end of the admission day. We used multivariable logistic regression to assess the association between lactate change and in-hospital mortality, and to identify interventions associated with lactate clearance. Results: Among 40,434 patients with cardiogenic shock, 30.1% achieved same-day lactate normalization, which was associated with lower in-hospital mortality (aOR 0.51; 95% CI 0.48-0.54). Lactate change showed the greatest prognostic importance, with observed mortality exceeding 80% among those with lactate increase >5 mmol/L regardless of baseline values. After adjustment, lactate change showed a positive exponential relationship with mortality, with aORs ranging from 0.25 (95% CI 0.23-0.27) for a -10 mmol/L change to 3.99 (95% CI 3.58-4.40) for a +10 mmol/L change. The intervention most strongly associated with early lactate clearance was pulmonary artery catheter (PAC; aOR 1.28 [95% CI 1.19-1.37]). Conclusions: Nearly 1 in 3 patients with cardiogenic shock achieved early lactate clearance, which was associated with lower mortality. The magnitude of lactate change had profound prognostic implications regardless of the initial value. Among day 1 interventions, PAC use had the strongest association with lactate clearance.

BackgroundAcute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are frequently associated with cardiac complications, including myocardial injury and right ventricular dysfunction. However, the mechanisms linking pulmonary injury to cardiac dysfunction remain incompletely understood. In this study, we investigated ventricular mitochondrial respiratory function during the acute phase of bleomycin-induced ALI. MethodsALI was induced in male and female rats by intratracheal bleomycin (2.5 mg/kg); saline served as a control. Circulating cardiac troponin I (cTnI) was measured as an indicator of myocardial injury. Mitochondrial respiration was assessed in permeabilized ventricular fibers using high-resolution respirometry (HRR). The mitochondrial respiration rate of the H9C2 cardiomyoblast cell line was performed using Seahorse Xfe96 Cell Mitochondrial Stress Test. Cells were treated with pro-inflammatory cytokine cocktails (PRO; IL1{beta} plus TNF plus IL6), anti-inflammatory cytokine cocktails (ANTI; IL4 plus IL10), a mixture of PRO and ANTI (BOTH), and (-)-norepinephrine (NE) in either hypoxic (1% oxygen) or normoxic conditions. ResultsBleomycin-induced ALI increased circulating cTnI levels in male rats, indicating early cardiac stress following lung injury. Mitochondrial respiration in the LV appeared to show modest alterations, with preserved oxidative phosphorylation (OXPHOS) and electron transport (ET) capacity. In contrast, the RV of male animals demonstrated marked reductions in absolute respiratory flux and substrate-supported OXPHOS capacity, indicating impaired mitochondrial oxidative capacity. Female animals exhibited greater preservation of mitochondrial respiratory function, particularly in the RV, with higher OXPHOS capacity and greater Complex I gain than males. H9C2 cells treated with PRO showed a significant increase in uncoupled respiration following 6- and 24-hour incubation periods, under normoxic conditions. Maximal respiration and spare respiratory capacity were increased following 24-hours under hypoxia. No significant changes were observed following treatment with NE alone and in combination with PRO under normoxia or hypoxia for 24 hours. ConclusionsALI induces ventricle-specific and sex-dependent alterations in cardiac mitochondrial bioenergetics, with pronounced impairment in males and relative mitochondrial resilience in females. In H9C2 cardiomyoblasts, short-term exposure (6-24 hours) to pro-inflammatory cytokines enhances uncoupled mitochondrial respiration under normoxic conditions, while short-term hypoxic exposure independently increases maximal respiration and spare respiratory capacity.

Objective: To compare RNA-sequencing-derived transcriptomic profiles of thoracic aortic aneurysm tissue from individuals with bicuspid versus trileaflet aortic valves. Methods: Human ascending aortic tissue was collected from patients undergoing cardiac surgery at a single institution between January 2021 and December 2022 with bicuspid aortic valves (BAV) and trileaflet aortic valves (TAV) with (-A) and without (-N) thoracic aortic aneurysm. TAV-N tissue was collected from heart transplant donors. The decision to perform ascending aortic replacement was at surgeon discretion following ACC/AHA guidelines. Bulk RNA was extracted from the aortic wall, and Illumina RNA Sequencing performed. Differential gene expression analysis, enrichment analyses, network analysis, and deconvolution single cell-mapping were performed in R. Cell-type specificity of differentially expressed genes was determined using an established Aorta single cell RNA sequencing matrix. Results: Tissue samples from 60 patients were included: 4 TAV-N, 16 BAV-N, 28 BAV-A, and 12 TAV-A. Average absolute aortic diameter was 5.1 +/- 0.38 cm for BAV-A and 5.3 +/- 0.44 cm for TAV-A, as measured on pre-operative CT. Gene ontology analyses of differentially expressed genes revealed enrichment of genes associated with extracellular matrix (ECM) organization, cellular receptor interactions and vascular smooth muscle cell (VSMC) function in BAV-A and BAV-N. In contrast, analysis of TAV-A versus TAV-N showed enrichment in genes associated with immune and inflammatory processes. Cell-type specificity analysis revealed a downregulation of genes associated with ECM components, cell signaling, and ECM remodeling in mesenchymal cells, VSMCs, and matrix fibroblasts specifically in BAV-A versus BAV-N. Conclusions: The transcriptome changes observed in aneurysmal aortas of BAV and TAV patients are distinct, suggesting mechanistic differences contributing to aneurysm development and progression. The observed differences in gene expression between the non-aneurysmal aortas may signify a predisposition to aneurysm development unique to BAV aortopathy.

Background: Anemia is nearly ubiquitous in hospitalized patients with congestive heart failure (CHF), yet little data informs the decision to transfuse blood in this population. Objectives: To determine average and heterogenous effects of blood transfusion in hospitalized patients with CHF. Methods: We performed a multicenter retrospective cohort study with individual treatment effect analysis using the Premier Healthcare Database (2022-2024). Adult patients with CHF hemoglobin concentrations between 6.5-7.4 g/dL were included. The exposure was blood transfusion based on hemoglobin concentration threshold of <7.0 g/dL. The primary outcome was hospital free days by day 28 (HFDs). We determined the average effect of transfusion using instrumental variable analysis based on a hemoglobin threshold of 7.0 g/dL and estimated the predicted effects of transfusions on HFDs (i.e., conditional average treatment effects) for individual patients using causal forest machine learning models. Results: We included 31,408 patients in a derivation cohort and 30,677 in a validation cohort, of which 13,437 (42.8%) and 13,334 (43.5%) received transfusions, respectively. The average association between transfusion and HFDs suggested harm (derivation mean difference -1.8 [95% CI -2.3, -1.3] days; validation mean difference -1.5 [95% CI -2.0, -1.0] days). However, the effects of transfusion were heterogenous (p=0.001) with the strongest drivers of transfusion benefit being transfusion on hospital day 1 and low serum bicarbonate concentration. Conclusions: The average association between transfusion and HFDs in hospitalized patients with CHF suggested harm; however, there were potential small benefits early in hospitalization and in those with low serum bicarbonate concentrations.

Background: Cardiogenic shock (CS) remains associated with high short-term mortality despite contemporary advances in care. The association between institutional cardiac capability and outcomes?particularly among transferred patients and after accounting for clinical instability?remains incompletely defined. Objectives: To evaluate the association between hierarchical hospital cardiac capability and in-hospital mortality using a latent measure of acute physiologic severity. Methods: Using the National Inpatient Sample (2016?2022), hospitals were classified into five hierarchical tiers ranging from non-PCI (Tier 1) to heart transplant/durable LVAD centers (Tier 5). Generalized structural equation modeling (GSEM) assessed the relationship between hospital tier and mortality. A latent "Acute Severity" construct?comprising cardiac arrest, acute kidney and liver injury, and mechanical ventilation?was incorporated to model the effects of clinical instability Results: Among an estimated 1,177,180 CS hospitalizations, most occurred at cardiac surgical and transplant/LVAD centers. Crude mortality declined stepwise from non-PCI hospitals (64.5%) to transplant/LVAD centers (36.5%). After adjustment, higher hospital tier was independently associated with lower mortality (Tier 2 OR 0.43 [95% CI 0.38?0.48]; Tier 3 OR 0.37 [0.32?0.43]; Tier 4 OR 0.33 [0.30?0.38]; Tier 5 OR 0.35 [0.31?0.40]). Although transfer-in status was associated with increased mortality (OR 1.39 [1.33?1.46]), this association was attenuated at cardiac surgical and transplant/LVAD centers, consistent with a mitigation of transfer associated risk. Conclusions: Higher hospital cardiac capability is independently associated with lower mortality in CS. Advanced centers are associated with mitigation transfer-associated risk, supporting regionalized hub-and-spoke systems with early referral to high-capability centers.

Severe forms of inflammation-induced acute and chronic myocarditis have a poor prognosis. Promising therapeutic efforts focused on monoclonal antibodies (mAbs) inhibiting inflammation-inducing molecules. However, most mAbs target only one or a limited number of such molecules. Since inflammation involves multiple redundant pathways, we postulated that an mAb inhibiting multiple inflammatory pathways would be a potent therapeutic agent. We initially tested the commercially available anti-natural killer (NK) cell mAb (anti-NK1.1), which binds a receptor expressed on NK cells and depletes them. Since NK cells are key cellular orchestrators of inflammation, by reducing their number, we aimed to inhibit multiple inflammatory pathways. Our initial studies demonstrated that administration of this antibody significantly improved myocardial outcomes in mouse models of acute myocardial infarction and of heart failure. Since NK1.1 is not expressed in human cells, we built on these promising preclinical results by developing a novel mAb targeting CD160 on human NK cells for evaluation as an immunosuppressive therapy. We found that the anti-CD160 mAb depletes both murine and human NK cells. We also found that, while CD160+ cells were largely present in the NK population, they also occurred among CD8+ and {gamma}/{delta} T cell subsets in human cells. Anti-CD160 therapy entirely prevented the deterioration of the myocardial function of mice with autoimmune-induced acute myocarditis. This outcome suggests our novel approach for inhibiting multiple inflammatory pathways may provide a potent strategy for improving outcomes of inflammation-driven myocarditis, as well as of other inflammation-driven diseases. Key PointsO_ST_ABSQuestionC_ST_ABSCan the depletion of CD160+ cells prevent autoimmune-induced myocarditis? FindingsIn this study we found that CD160 is expressed by mouse and human natural killer cells and other subtypes of cytotoxic T cells, and that a monoclonal antibody targeting CD160 depletes NK cells. In a preclinical model of experimental autoimmune myocarditis, administration of the anti-CD160 monoclonal antibody prevented myocardial dysfunction and systemic inflammation. MeaningOur results are compatible with the hypothesis that early autoimmune-induced myocardial dysfunction is promoted by CD160+ cells, which elevate inflammation-induced circulating factors (or factors released by tissue-resident cytotoxic immune cells) that cause myocardial dysfunction in the absence of myocardial necrosis or fibrosis, and further, that targeting CD160+cells with a mAb that depletes NK cells (and probably CD160 expressing cytotoxic T cells) entirely prevents the deterioration of myocardial function in such mice. This outcome suggests our novel approach for inhibiting multiple inflammatory pathways may provide a potent strategy for improving outcomes of inflammation-driven myocarditis, as well as of other inflammation-driven diseases.

Background Exercise capacity varies among individuals with a Fontan circulation. Percent predicted peak oxygen consumption (%pVO2) may be influenced by ventricular morphology, Fontan subtype, and conduit characteristics, but data explaining variability in exercise capacity are limited. This study examined whether anatomical and surgical factors are associated with %pVO2 later in life. Methods Participants enrolled in the multicenter Single Ventricle Outcomes Network (SV-ONE) database who had cardiopulmonary exercise testing (CPET) data were included. Published reference equations were used to estimate %pVO2. Multivariable regression models evaluated associations between anthropometric, anatomical (diagnosis and dominant ventricle), and surgical (Fontan subtype, conduit size, and surgical era) factors and %pVO2. Restricted spline analyses assessed nonlinearity. Results 561 individuals with a Fontan circulation were included in the analysis; age 20 {+/-} 8 years, 54% male, mean %pVO2 was 63 {+/-} 16%. Sex and exercise modality were the strongest predictors of %pVO2, with females being 12% higher than males and treadmill 4.6% higher than a cycle. Age at CPET was a predictor of exercise capacity with %pVO2 decreasing by 0.8% per year. Ventricular morphology, diagnosis, and Fontan subtype did not have a statistical association with the primary outcome. In models restricted to patients with an extracardiac conduit (n = 330), conduit diameter and area were not associated with %pVO2, even after indexing to body surface area. Univariable nonlinear spline analyses suggested an optimal conduit size of 18 mm for %pVO2, but this was not significant after body size adjustments. Conclusion In this large multicenter cohort, surgical and anatomical features were not as important as sex, age, and body size as determinants of exercise performance in patients with a Fontan circulation. Reduced exercise capacity in this population appears to reflect progressive pathophysiological changes of the Fontan circulation rather than specific characteristics such as conduit size, ventricular morphology, or anatomy.

BackgroundST-elevation myocardial infarction (STEMI) is reported to be a leading cause of mortality worldwide. While cardiac troponins are the gold standard for myocardial injury detection but creatine kinase-MB (CK-MB) and total creatine phosphokinase (CPK) retain prognostic use in resource-limited settings. ObjectiveTo evaluate the prognostic significance of admission CK-MB and CPK levels in STEMI patients and to assess their association with hematological parameters for integrated risk stratification. MethodsThis cross-sectional study enrolled 15 consecutive STEMI patients from the Punjab Institute of Cardiology, Lahore, during January 2024. Comprehensive laboratory analysis including cardiac biomarkers (CK-MB, CPK, troponin-I, LDH), complete blood count, renal function, serum electrolytes, and metabolic parameters, was performed on admission. Pearson correlation and comparative statistical analyses were also conducted to assess the relationships between cardiac biomarkers and hematological indices. ResultsThe cohort includes 15 patients (mean age 50.1 {+/-} 12.2 years; 73.3% male). Cardiac biomarker elevation was prevalent: CK-MB was elevated in 12/15 (80%), CPK was elevated in 12/15 (80%), with concordant elevation in 11/15 (73.3%), which indicates extensive myocardial necrosis. Troponin-I showed the highest elevation rate at 13/15 (86.7%). Hematological abnormalities included anemia (60%), WBC elevation (53.3%), and RBC reduction (40%). Random glucose averaged 150.80 {+/-} 63.55 mg/dL, with 66.7% highlighted the hyperglycemia. Remarkably, electrolyte balance was preserved in all of the patients (0% sodium, potassium, and bicarbonate abnormalities), indicating maintained homeostasis. Pearson correlation analysis revealed a significant correlation between CK-MB and CPK (r = 0.615, p = 0.0126), while correlations between cardiac biomarkers and hematological parameters were weak (p > 0.05). Risk stratification identified 53.3% of patients as high-risk who required intensive management. ConclusionsCK-MB and CPK demonstrate significant concordance and retain prognostic value in STEMI patients, particularly in resource-limited settings where troponin access may be constrained. While troponin-I remains the most sensitive biomarker, combined assessment of conventional cardiac enzymes supports reliable evaluation of myocardial injury. Hematological parameters reflect systemic response but show limited correlation with cardiac biomarkers.

Sickle cell disease (SCD) is associated with substantial cardiovascular morbidity, but echocardiographic data from Latin American populations remain scarce. We aimed to characterise the structural, functional, and haemodynamic echocardiographic profile of adults with SCD attending a tertiary referral centre in Cali, Colombia. We conducted an observational, cross-sectional study based on systematic review of medical records and transthoracic echocardiography reports of consecutive adult patients ([&ge;]18 years) with confirmed SCD evaluated between January 2022 and December 2024. Patients with complex congenital heart disease, severe valvular disease of unrelated aetiology, pregnancy, or echocardiograms of insufficient quality were excluded. Of 669 patients screened, 57 met inclusion criteria. Reporting followed STROBE recommendations. The median age was 24 years (interquartile range [IQR] 21-32) and 59.6% were female; the SS genotype was the most frequent (76.4%) and 71.4% were on hydroxyurea. Median haemoglobin was 10.2 g/dL (IQR 9.3-11.4) and median NT-proBNP 491 pg/mL (IQR 98-1290). Most patients had preserved left ventricular dimensions and systolic function (median ejection fraction 63%, IQR 57-66.5; mean global longitudinal strain -18.9% {+/-} 2.9). Right ventricular function was preserved (mean tricuspid annular plane systolic excursion 25.4 {+/-} 4.6 mm). Left ventricular geometry was normal in 42.1%, with concentric remodelling in 24.6%, concentric hypertrophy in 21.1%, and eccentric hypertrophy in 12.3%. Diastolic function was normal in 71.4%. Valvular disease, when present, was predominantly mild. Tricuspid regurgitation velocity exceeded 2.5 m/s in 29.8% of patients and exceeded 3.0 m/s in 10.5%, identifying a substantial subgroup at intermediate-to-high probability of pulmonary hypertension. In this Colombian cohort of relatively young adults with SCD, cardiac structure and biventricular function were largely preserved, but nearly one-third of patients had echocardiographic findings suggestive of pulmonary hypertension. These findings support the routine use of transthoracic echocardiography as an accessible tool for early cardiovascular risk stratification in adults with SCD in low- and middle-income settings.

BackgroundDelirium, a common and multifactorial complication after cardiac surgery, is influenced by several factors including inflammation, metabolic disturbances, and cerebral hypoperfusion. Because these factors can be reflected in an elevated anion gap (AG), we hypothesized that a higher preoperative albumin corrected anion gap (ACAG) is associated with increased risk of delirium and 1-year mortality after cardiac surgery. MethodsWe examined a retrospective cohort of adult patients within our healthcare system who underwent cardiac surgery between 2014 and 2022 and had a recorded Confusion Assessment Method for the ICU (CAM-ICU) evaluation. Patients were excluded if they had documented preoperative delirium during the index hospital admission or a history of dementia. The final cohort included 4,482 patients. Preoperative laboratory values were collected, using the most recent results obtained within 48 hours prior to surgery. The primary outcome was delirium after cardiac surgery (DACS), defined as delirium occurring within postoperative days 1 through 5. The secondary outcome was all-cause 1-year mortality. ResultsThe incidence of DACS and 1-year mortality were 9.5% and 4.8%, respectively. A multivariable logistic regression model adjusting for baseline characteristics showed that higher ACAG was significantly associated with higher risk of DACS (adjusted odds ratio (AOR) = 1.56, 95% Confidence Interval (CI) = 1.40-1.74, p < 0.001). Other predictors of DACS included increasing age (AOR = 1.31, CI = 1.16-1.48, p < 0.001), surgery duration (AOR = 1.35, CI = 1.22-1.49, p < 0.001), and history of delirium (AOR = 1.70, CI = 1.29-2.24, p < 0.001). Moreover, increasing ACAG was also associated with 1-year mortality (AOR = 1.35, CI = 1.16-1.56, p < 0.001). Finally, receiver operating characteristic (ROC) analysis demonstrated that ACAG exhibited superior predictive performance compared with AG and anion gap to bicarbonate ratio (AGBR) for both DACS and 1-year mortality outcomes. ConclusionsHigher preoperative ACAG was associated with elevated risk for DACS and 1-year mortality. Preoperative ACAG is an accessible and cost-efficient biomarker that may improve risk stratification for cardiac surgery patients.

BackgroundPatients with systemic lupus erythematosus (SLE) face markedly increased cardiovascular disease (CVD) risk driven by mechanisms beyond traditional risk factors. Thoracic aortic perivascular adipose tissue (tPVAT) is dysfunctional in lupus and exacerbates endothelial dysfunction, yet the molecular basis of this dysfunction remains poorly defined. MethodsIntegrated multi-omics profiling, including bulk RNA-seq, untargeted proteomics, lipidomics, and high-dimensional spectral flow cytometry, was performed on tPVAT from 15-week-old MRL/lpr mice (active lupus, n = 4-6) and MRL control mice (n = 5-6). Adipogenic differentiation capacity of tPVAT adipose stromal and progenitor cells (ASPCs) from MRL/lpr was assessed by Oil Red O staining at 5 (pre-dieasea) and 15 weeks (active disease), with subcutaneous ASPCs used as depot controls. ResultsTranscriptomic profiling of tPVAT from MRL/lpr mice identified 2,742 upregulated and 1,494 downregulated genes (adjusted p < 0.001, |log2FC| > 1), with strong activation of interferon, IL6-JAK-STAT3, and TNFA signaling pathways together with suppression of fatty acid metabolism, oxidative phosphorylation, and adipogenic pathways. Proteomic and lipidomic analyses were concordant, revealing broad downregulation of mitochondrial bioenergetic machinery, depletion of cardiolipin and acylcarnitines, and enrichment of ceramide phosphoinositols and lysophosphatidylcholines. Cardiolipin strongly correlated with the mitochondrial/metabolic protein module (r = 0.95) and inversely with the immune/inflammatory protein module (r = -0.92). Spectral flow cytometry confirmed marked CD45+ leukocyte infiltration dominated by T cells, together with a significantly reduced Treg/CD4+ ratio indicating loss of local immunoregulatory balance. ASPCs derived from PVAT of 15-week-old MRL/lpr mice exhibited impaired white and beige adipogenic differentiation, while APCs from PVAT of 5-week-old MRL/lpr mice, and from subcutaneous adipose tissues of 15-week-old MRL/lpr mice, had normal white and beige differentiation, consistent with an acquired, depot-specific, disease-stage-dependent progenitor defect in PVAT of MRL/lpr mice. ConclusionsLupus tPVAT undergoes a concordant cross-platform molecular reprogramming of mitochondrial bioenergetic genes coupled with establishment of an interferon-dominant immune niche and acquired loss of ASPC adipogenic capacity. These findings provide a molecular framework for lupus PVAT dysfunction and identify restoration of mitochondrial function, suppression of interferon-driven inflammation, and renewal of progenitor differentiation as potential therapeutic strategies for lupus vasculopathy.

BackgroundPulmonary artery (PA) wave reflection is a key determinant of right ventricular (RV) afterload. RV function is the most important factor determining long-term prognosis in patients with surgically repaired tetralogy of Fallot (rTOF). This study aimed to evaluate PA wave reflection in rTOF using RV pressure phase plane (PPP) analysis, and to identify the clinical, morphological, and hemodynamic characteristics associated with increased PA wave reflection in patients with rTOF. MethodsAugmentation pressure (AugPr) during late systole was quantified using the inflection point of systolic dP/dt on the PPP. The ratio of AugPr to RV systolic pressure (RVSP) was defined as the AugPr index. The study included 87 patients with rTOF (mean age, 15.9 {+/-} 10.0 years), 17 control subjects (13.3 {+/-} 6.3 years), and seven patients with pulmonary arterial hypertension (PAH) (16.4 {+/-} 11.7 years). The rTOF cohort was categorized according to surgical procedure: pulmonary valve-sparing repair (PVS, n = 5), transannular patch repair (TAP, n = 34), and the Rastelli procedure (n = 48). ResultsThe prevalence of AugPr was 0% in the control group, 100% in the PAH group, and 26.4% in the rTOF group (p < 0.0001). Among the surgical subgroups, the prevalence was 0% in PVS, 14.7% in TAP, and 41.7% in the Rastelli group (p < 0.0027). AugPr and the AugPr index were significantly higher in the Rastelli group than in the other two groups (p = 0.0447 and 0.0433, respectively). In addition, AugPr showed significant correlations with RVSP, RV outflow tract obstruction, maximal dP/dt, and pulmonary regurgitation grade (all p < 0.05). ConclusionsPA wave reflection can be clearly visualized using PPP. The Rastelli group demonstrated a higher prevalence and magnitude of PA wave reflection, suggesting a greater increase in RV afterload compared with other surgical repair types.

Background and AimsAcute myocarditis (AM) is a T cell-mediated myocardial disease with clinical manifestations ranging from mild chest pain to cardiogenic shock. Reliable biomarkers to stratify patients and guide therapy are currently lacking. In particular, the extent of the dysregulation of inflammatory pathways, and the impact on myocardial dysfunction, remain elusive. MethodsSerum analyses were performed in prospectively recruited AM patients (n = 103) from two independent cohorts. Multimodal data integration combining profiling of cytokine and chemokine dysregulation with clinical biomarkers was used to define clinical phenotypes with distinct inflammatory signatures. Machine-learning and regression models were applied to determine biomarkers that indicate clinical severity. ResultsImmuno-proteomic profiling revealed conserved inflammatory patterns across AM cohorts, dominated by T cell-related cytokines and chemokines. In addition, AM patients showed dysregulation of fibroblast-derived cytokines, including hepatocyte growth factor (HGF), bone morphogenic protein 4 (BMP4) and the BMP4 inhibitors Gremlin-1 (GREM1) and Gremlin-2 (GREM2). Data integration and unsupervised clustering revealed two immuno-clinical phenotypes, linking T cell activation and fibroblast dysregulation to disease severity. Machine learning-based analysis identified CXCL10, GREM2 and LVEF as critical parameters for stratifying disease severity. ConclusionsThese findings highlight a systemic T cell activation signature as diagnostic hallmark of AM. In addition, dysregulation of fibroblast-derived tissue cytokines serves as an indicator for distinct immuno-clinical phenotypes in myocardial inflammatory disease. Thus, the clinically relevant link between T cell-driven immune activation, myocardial inflammation and fibroblast-driven remodelling provides a versatile set of parameters to identify severe manifestations of AM. Graphical AbstractKey Question: Are serological immune signatures linked to clinical severity in acute myocarditis and do they enable patient stratification? Key Findings: T cell- and fibroblast associated proteomic signatures indicate disease severity in acute myocarditis. Novel immuno-clinical phenotypes stratify patients according to distinct immune responses and clinical manifestations. CXCL10, GREM2 and LVEF are the most important parameters to identify immuno-clinical phenotypes. Take Home Message: CXCL10, GREM2 and LVEF emerge as key determinants for a severe immuno-clinical phenotype in acute myocarditis, highlighting the role of T cell-fibroblast interaction in the disease process and linking T cell activation, fibroblastic tissue remodelling and impaired cardiac function. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=83 SRC="FIGDIR/small/26350598v1_ufig1.gif" ALT="Figure 1"> View larger version (33K): org.highwire.dtl.DTLVardef@362a7borg.highwire.dtl.DTLVardef@1ef158org.highwire.dtl.DTLVardef@176fbc2org.highwire.dtl.DTLVardef@8a93d9_HPS_FORMAT_FIGEXP M_FIG C_FIG