Effects of interventions targeting the systemic inflammatory response to cardiac surgery on clinical outcomes in adults.

BACKGROUND: Organ injury is a common and severe complication of cardiac surgery that contributes to the majority of deaths. There are no effective treatment or prevention strategies. It has been suggested that innate immune system activation may have a causal role in organ injury. A wide range of organ protection interventions targeting the innate immune response have been evaluated in randomised controlled trials (RCTs) in adult cardiac surgery patients, with inconsistent results in terms of effectiveness. OBJECTIVES: The aim of the review was to summarise the results of RCTs of organ protection interventions targeting the innate immune response in adult cardiac surgery. The review considered whether the interventions had a treatment effect on inflammation, important clinical outcomes, or both. SEARCH METHODS: CENTRAL, MEDLINE, Embase, conference proceedings and two trial registers were searched on October 2022 together with reference checking to identify additional studies. SELECTION CRITERIA: RCTs comparing organ protection interventions targeting the innate immune response versus placebo or no treatment in adult patients undergoing cardiac surgery where the treatment effect on innate immune activation and on clinical outcomes of interest were reported. DATA COLLECTION AND ANALYSIS: Searches, study selection, quality assessment, and data extractions were performed independently by pairs of authors. The primary inflammation outcomes were peak IL-6 and IL-8 concentrations in blood post-surgery. The primary clinical outcome was in-hospital or 30-day mortality. Treatment effects were expressed as risk ratios (RR) and standardised mean difference (SMD) with 95% confidence intervals (CI). Meta-analyses were performed using random effects models, and heterogeneity was assessed using I2. MAIN RESULTS: A total of 40,255 participants from 328 RCTs were included in the synthesis. The effects of treatments on IL-6 (SMD -0.77, 95% CI -0.97 to -0.58, I2 = 92%) and IL-8 (SMD -0.92, 95% CI -1.20 to -0.65, I2 = 91%) were unclear due to heterogeneity. Heterogeneity for inflammation outcomes persisted across multiple sensitivity and moderator analyses. The pooled treatment effect for in-hospital or 30-day mortality was RR 0.78, 95% CI 0.68 to 0.91, I2 = 0%, suggesting a significant clinical benefit. There was little or no treatment effect on mortality when analyses were restricted to studies at low risk of bias. Post hoc analyses failed to demonstrate consistent treatment effects on inflammation and clinical outcomes. Levels of certainty for pooled treatment effects on the primary outcomes were very low. AUTHORS' CONCLUSIONS: A systematic review of RCTs of organ protection interventions targeting innate immune system activation did not resolve uncertainty as to the effectiveness of these treatments, or the role of innate immunity in organ injury following cardiac surgery.

Nanopore sequencing of DNA-barcoded probes for highly multiplexed detection of microRNA, proteins and small biomarkers.

There is an unmet need to develop low-cost, rapid and highly multiplexed diagnostic technology platforms for quantitatively detecting blood biomarkers to advance clinical diagnostics beyond the single biomarker model. Here we perform nanopore sequencing of DNA-barcoded molecular probes engineered to recognize a panel of analytes. This allows for highly multiplexed and simultaneous quantitative detection of at least 40 targets, such as microRNAs, proteins and neurotransmitters, on the basis of the translocation dynamics of each probe as it passes through a nanopore. Our workflow is built around a commercially available MinION sequencing device, offering a one-hour turnaround time from sample preparation to results. We also demonstrate that the strategy can directly detect cardiovascular disease-associated microRNA from human serum without extraction or amplification. Due to the modularity of barcoded probes, the number and type of targets detected can be significantly expanded.

Relación entre el Finnish Diabetes Risk Score, glucemia en ayunas y hemoglobina A1c / Relationship between the Finnish Diabetes Risk Score, fasting blood glucose and glycohemoglobin A1c

Introducción: el Finnish Diabetes Risk Score (FINDRISC) mostró alta sensibilidad y especificidad para la detección de personas que evolucionarían a diabetes mellitus (DM) en las poblaciones estudiadas, por lo cual se decidió utilizarlo entre quienes concurrieron por diferentes motivos a realizarse análisis de laboratorio en centros de la Asociación de Laboratorios de Alta Complejidad (ALAC), con el objeto de identificar personas con diferentes niveles de riesgo de presentar alteraciones de la glucemia en ayunas (GA) y de la HbA1c. Objetivos: explorar la asociación entre la puntuación del FINDRISC con GA y HbA1c, estableciendo el punto de corte de mayor sensibilidad y especificidad para encontrar una GA ≥100 mg/dL y una HbA1c ≥5,7% (38,8 mmol/mol), en una población que concurrió a centros de la ALAC. Materiales y métodos: se incluyeron 1.175 individuos de 45 laboratorios de la ALAC, procesamiento local de glucemia y centralizado de HbA1c (high performance liquid chromatography, HPLC). Análisis estadístico: chi-cuadrado, Odds Ratio, ANOVA, test de Tukey, regresión logística binomial y curvas ROC. Resultados: los puntajes totales del FINDRISC se asociaron de manera positiva y estadísticamente significativa, tanto con los valores de GA como con los niveles de HbA1c. Entre sus variables, una edad mayor o igual a 45 años, un perímetro abdominal de alto riesgo, un índice de masa corporal mayor o igual a 25 Kg/m., la presencia de antecedentes familiares de DM (padres, hermanos o hijos) y la existencia de antecedentes de medicación antihipertensiva se asociaron de manera significativa con valores de GA iguales o superiores a 100 mg/dL y/o niveles de HbA1c iguales o mayores a 5,7% (38,8 mmol/mol). No se halló asociación significativa con la realización de actividad física (al menos 30 minutos diarios) ni con el registro de ingesta diario de frutas y verduras. Los valores medios de GA y HbA1c en individuos con puntajes totales del FINDRISC menores o iguales a 11 fueron de 89,9 mg/dL y 5,2% (33,0 mmol/mol), respectivamente, elevándose hasta valores medios de 116,1 mg/dL y 6,1% (43,0 mmol/mol) en los individuos con puntajes iguales o superiores a 21, siguiendo una asociación del tipo "dosis/respuesta". Por curvas ROC, un FINDRISC de 13 presenta una sensibilidad del 81,89%, especificidad del 67,60% y 70,55% de diagnósticos correctos de HbA1c ≥5,7% (38,8 mmol/mol), y una sensibilidad del 72,50%, especificidad del 70,62% y 71,20% de diagnósticos correctos para encontrar personas con una GA ≥100 mg/dL. Conclusiones: el puntaje del FINDRISC se relacionó con niveles crecientes de GA y HbA1c, resultando útil para encontrar personas con GA ≥100 mg/dL y HbA1c ≥5,7% (38,8 mmol/mol) en la población estudiada.

Introduction: the Finnish Diabetes Risk Score (FINDRISC) has high sensitivity and specificity for the identification of people at risk of diabetes mellitus (DM) in various populations. Therefore, we aimed to use this index to identify individuals at risk of having alterations in fasting glycemia (FG) and HbA1c among those who underwent laboratory analysis at ALAC, Argentina. Objectives: to explore the relationships of the FINDRISC score with the fasting blood glucose (FG) concentration and glycated hemoglobin (HbA1c) level, and to establish appropriate cut-off scores to predict FG ≥100 mg/dL and HbA1c ≥5.7% (38.8 mmol/mol) in this population. Materials and methods: we recruited 1,175 individuals from 45 ALAC laboratories for whom FG and HbA1c had been measured. We analyzed the data using the chi square test, odds ratios, ANOVA plus Tukey's post-hoc test, binomial logistic regression, and receiver operating characteristic (ROC) curves. Results: total FINDRISC score significantly positively correlated with both FG and HbA1c. Of the constituent variables, age ≥45 years, a large waist circumference, a body mass index ≥25 kg/m., a close family history of DM, and the use of antihypertensive medication were significantly associated with FG ≥100 mg/dL and/or HbA1c ≥5.7% (38.8 mmol/mol). However, no significant association was found with physical activity or the daily consumption of fruit and vegetables. The mean FG and HbA1c for individuals with total FINDRISC scores ≤11 were 89.9 mg/dL and 5.2% (33.0 mmol/mol), respectively, which increased to 116.1 mg/dL and 6.1% (43.0 mmol/mol) for individuals with scores ≥21, with a dose/response-type relationship. ROC analysis showed that a FINDRISC of 13 was associated with a sensitivity of 81.89%, a specificity of 67.60%, and a correct diagnosis rate of 70.55% for HbA1c ≥5.7% (38.8 mmol/mol); and a sensitivity of 72.50%, a specificity of 70.62%, and a correct diagnosis rate of 71.20% for FG ≥100 mg/dL. Conclusions: FINDRISC score increases with increasing FG and HbA1c, and is a useful means of identifying people with FG ≥100 mg/dL and HbA1c ≥5.7% (38.8 mmol/mol).

Functional LTCC-ß2AR Complex Needs Caveolin-3 and Is Disrupted in Heart Failure.

BACKGROUND: Beta-2 adrenergic receptors (ß2ARs) but not beta-2 adrenergic receptors (ß1ARs) form a functional complex with L-type Ca2+ channels (LTCCs) on the cardiomyocyte membrane. However, how microdomain localization in the plasma membrane affects the function of these complexes is unknown. We aim to study the coupling between LTCC and ß adrenergic receptors in different cardiomyocyte microdomains, the distinct involvement of PKA and CAMKII (Ca2+/calmodulin-dependent protein kinase II) and explore how this functional complex is disrupted in heart failure. METHODS: Global signaling between LTCCs and ß adrenergic receptors was assessed with whole-cell current recordings and western blot analysis. Super-resolution scanning patch-clamp was used to explore the local coupling between single LTCCs and ß1AR or ß2AR in different membrane microdomains in control and failing cardiomyocytes. RESULTS: LTCC open probability (Po) showed an increase from 0.054±0.003 to 0.092±0.008 when ß2AR was locally stimulated in the proximity of the channel (<350 nm) in the transverse tubule microdomain. In failing cardiomyocytes, from both rodents and humans, this transverse tubule coupling between LTCC and ß2AR was lost. Interestingly, local stimulation of ß1AR did not elicit any change in the Po of LTCCs, indicating a lack of proximal functional interaction between the two, but we confirmed a general activation of LTCC via ß1AR. By using blockers of PKA and CaMKII and a Caveolin-3-knockout mouse model, we conclude that the ß2AR-LTCC regulation requires the presence of caveolin-3 and the activation of the CaMKII pathway. By contrast, at a cellular "global" level PKA plays a major role downstream ß1AR and results in an increase in LTCC current. CONCLUSIONS: Regulation of the LTCC activity by proximity coupling mechanisms occurs only via ß2AR, but not ß1AR. This may explain how ß2ARs tune the response of LTCCs to adrenergic stimulation in healthy conditions. This coupling is lost in heart failure; restoring it could improve the adrenergic response of failing cardiomyocytes.

Opiniones y recomendaciones de la Sociedad Argentina de Diabetes. Hemoglobina A1c / Opinions and recommendations of the Argentine Diabetes Society. Hemoglobin A1c

La estandarización de la hemoglobina A1c (HbA1c) permitió en algunos países su uso para el diagnóstico de la diabetes mellitus (DM) y la prediabetes, además de su empleo en el seguimiento del paciente con DM. Es importante recordar que se trata de una medida indirecta del promedio glucémico durante el tiempo de vida media del eritrocito, pudiendo verse afectada por variables no glucémicas, como también por interferencias analíticas según la metodología empleada para su determinación. A continuación, se describen las recomendaciones y consideraciones a tener en cuenta para la determinación de la HbA1c cuando se emplea como criterio diagnóstico de la DM, teniendo en cuenta que al utilizarla para tal fin es necesario que la medida se realice con métodos certificados y estandarizados al ensayo utilizado en el Diabetes Control and Complications Trial (DCCT).

The standardization of hemoglobin A1c (HbA1c) allowed in some countries its use for the diagnosis of diabetes mellitus (DM) and prediabetes, in addition to its use in the follow-up of patients with DM. It is important to highlight that it is an indirect measurement of the glycemic average during the halflife of the erythrocyte, and may be affected by non-glycemic variables, as well as by analytical interferences depending on the methodology used for its determination. The recommendations and considerations to take into account for the determination of HbA1c when it is used as a diagnostic criterion for diabetes are described below. In addition, it is important to emphasize that it is essential that the HbA1c measurement be performed with certified and standardized methods to the Diabetes Control and Complications Trial (DCCT)results.

Opiniones y recomendaciones de la Sociedad Argentina de Diabetes. Glucemia en ayunas alterada: ¿es oportuno utilizar el punto de corte en 100 mg/dl en Argentina? / Opinions and recommendations of the Argentine Diabetes Society. Impaired fasting blood glucose: is it appropriate to use a cut-off point of 100 mg/dl in Argentina?

Establecer el punto de corte entre la glucemia en ayunas normal y la alterada resulta de suma importancia a los efectos de considerar a un paciente en riesgo, tanto de progresar a estdos más avanzados de la enfermedad como de sufrir complicaciones micro y macroangiopáticas. Desde 2006 la Sociedad Argentina de Diabetes (SAD), sobre la base de la evidencia considerada en ese momento, estableció el límite inferior de la glucemia alterada en ayunas (GAA) en 110 mg/dl; posteriormente, durante 2022, la Comisión Directiva de la SAD convocó a un grupo de expertos con el objeto de evaluar si esta recomendación debía mantenerse o, al igual que otras sociedades científicas de prestigio, adoptar a tal efecto 100 mg/dl. En este documento de Opiniones y Recomendaciones se encuentran los fundamentos por los cuales la SAD adoptará, de ahora en más, 100 mg/dl como límite inferior de la GAA, en base a las nuevas evidencias científicas que muestran que desde este punto de corte se produce un aumento en la progresión a la diabetes mellitus y de las complicaciones tanto macro como microangiopáticas.

To establish the cut-off point between normal and impaired fasting glycemia (IFG) is extremely important for the purposes of considering a patient at risk both of progressing to more advanced stages of the disease and of suffering micro- and macroangiopathic complications. Since 2006, the Argentine Diabetes Society (ADS), based on the evidence considered at that time, established the lower limit of IFG at 110 mg/d, laterduring the year 2022, The Board of Directors of the ADS vened a group of experts in order to assess whether this recommendation should be maintained or, like other prestigious scientific societies, adopt 100 mg/dl for this purpose. This Opinions and Recommendations document contains therationale for which the SAD will adopt, from now on, 100 mg/dlas the lower limit of the IFG, based on the new scientific edence that shows that from this cut-off point it produces increase in progression to diabetes and both macro and microangiopathic complications.

Glucemia en ayunas entre 100 y 109 mg/dL versus prediabetes según hemoglobina glicosilada / Fasting blood glucose between 100 and 109 mg/dL versus prediabetes according to glycosylated hemoglobin

Introducción: algunos estudios han señalado que valores de glucemia en ayunas entre 100 y 109 mg/dL se asocian con frecuencias elevadas de prediabetes cuando el criterio de clasificación son los valores de HbA1c. La Sociedad Argentina de Diabetes (SAD) sostiene a 110 mg/dL como valor a partir del cual se clasifica a un paciente como portador de glucemia en ayunas alterada; la frecuencia de individuos posiblemente clasificados en forma incorrecta, según este criterio, aún no se conoce en la población argentina. Objetivos: establecer la frecuencia con que se presenta prediabetes según HbA1c en una población sin diagnóstico de diabetes mellitus (DM) con glucemias en ayunas entre 100 y 109 mg/dL; correlacionar las dos variables y cuantificar la probabilidad de que esto ocurra respecto de otros con glucemias en ayunas <100 mg/dL. Materiales y métodos: se incluyeron 1.002 muestras de igual número de sujetos desde 45 laboratorios de análisis clínicos de la Asociación de Laboratorios de Alta Complejidad (ALAC), con procesamiento local de glucemia y centralizado de HbA1c por high performance liquid chromatography (HPLC). Análisis estadístico: chi cuadrado, odds ratio, coeficiente de correlación y determinación de Pearson, y correlación serial de Durbin-Watson. Resultados: frecuencia de HbA1c ≥5,7% en la población estudiada con glucemias de ayunas entre 100 y 109 mg/dL=29,7%; test de chi cuadrado: p<0,001; odds ratio de tener HbA1c ≥5,7% entre la población con glucemias en ayunas de 100 a 109 mg/dL vs aquella con valores <100 mg/dL=4,328 (IC 95% 2,922-6,411); r=0,852, r2 = 0,727, Durbin-Watson=1,152. Conclusiones: la prediabetes diagnosticada por HbA1c resultó cuatro veces más frecuente en la población estudiada con glucemias en ayunas entre 100 y 109 mg/dL, que en aquella con valores por debajo de 100 mg/dL.

Introduction: some studies have shown that fasting blood glucose values between 100 and 109 mg/dL are associated with high rates of prediabetes when the classification criteria are HbA1c values. The Argentine Diabetes Society still maintains 110 mg/dL as the value from which a patient is classified as having impaired fasting blood glucose; the frequency of individuals possibly incorrectly classified, according to this criterion, is not yet known in any Argentine population. Objectives: to establish the frequency in a population without a diagnosis of diabetes mellitus with fasting blood glucose levels between 100 and 109 mg/dL in which prediabetes occurs according to HbA1c, to correlate both variables and to quantify the probability that this predicts with respect to others with fasting blood glucose levels <100 mg/dL. Materials and methods: 1.002 samples from the same number of subjects from 45 clinical laboratories belonging to ALAC, with local processing of blood glucose and centralized processing of HbA1c by high performance liquid chromatography (HPLC). Statistical analysis: chi square, odds ratio, Pearson correlation coefficient, coefficient of determination and Durbin-Watson serial correlation. Results: frequency of HbA1c ≥5.7% in the studied population with fasting blood glucose levels between 100 and 109 mg/ dL = 29.7%, chi square test: p<0.001; odds ratio of having HbA1c ≥5.7% between the population with fasting blood glucose levels of 100 to 109 mg/dL vs that one with values <100 mg/dL=4.328 (95% CI 2.922-6.411); r=0.852, r2 =0.727, DurbinWatson=1.152. Conclusions: prediabetes diagnosed by HbA1c was four times more frequent in the studied population with fasting glucose values between 100 and 109 mg/dL than in that one with values below 100 mg/dL.

Balloon Nudge Technique: A Touch to Nonsteerable Valves.

Transfemoral transcatheter aortic valve replacement is an effective treatment for severe aortic stenosis with a high rate of procedural success with the current devices. However, anatomic factors and device limitations may increase technical difficulty. We describe the balloon nudge technique, a novel technique that improves coaxial alignment while crossing the aortic valve. (Level of Difficulty: Advanced.).

Similar outcome of tricuspid valve repair and replacement for isolated tricuspid infective endocarditis.

AIMS: To compare early and late mortality of acute isolated tricuspid valve infective endocarditis (TVIE) treated with valve repair or replacement. METHODS: Patients who were surgically treated for TVIE from 1983 to 2018 were retrieved from the Italian Registry for Surgical Treatment of Valve and Prosthesis Infective Endocarditis. All the patients were followed up by means of phone interview or calling patient referral physicians or cardiologists. Kaplan-Meier method was used to assess late survival and survival free from TVIE recurrence with log-rank test for univariate comparison. The primary end points were early mortality (30 days after surgery) and long-term survival free from TVIE recurrence. RESULTS: A total of 4084 patients were included in the registry. Among them, 149 patients were included in the study. Overall, 77 (51.7%) underwent TV repair and 72 (48.3%) TV replacement. Early mortality was 9% (13 patients). Expected early mortality according to EndoSCORE was 12%. The TV repair showed lower mortality and major complication rate (7% and 16%), compared with TV replacement (11% and 25%), but statistical significance was not reached. Median follow-up was 19.1 years (14.3-23.8). Late deaths were 30 and IE recurrences were 5. No difference in cardiac survival free from IE was found between the two groups after 20 years (80 ±â€Š6% Repair Group vs 59 ±â€Š13% Replacement Group, P = 0.3). CONCLUSIONS: Overall results indicate that once surgically addressed, TVIE has a low recurrence rate and excellent survival, apparently regardless of the type of surgery used to treat it.

Sex Differences in Outcomes After Percutaneous Coronary Intervention or Coronary Artery Bypass Graft for Left Main Disease: From the DELTA Registries.

Background Controversy exists over whether sex has significant interaction with revascularization strategy for unprotected left main coronary artery disease. Higher mortality has been reported among women treated with percutaneous coronary intervention compared with coronary artery bypass grafting. Methods and Results The DELTA (Drug-Eluting Stents for Left Main Coronary Artery Disease) and DELTA-2 registries are international, multicentric registries evaluating the outcomes of subjects undergoing coronary revascularization for unprotected left main coronary artery disease. The primary outcome was a composite of death, myocardial infarction, or cerebrovascular accidents. The population consisted of 6253 patients, including 1689 (27%) women. Women were older and more likely to have diabetes and chronic kidney disease than men (P<0.05). At a median follow-up of 29 months (interquartile range 12-49), a significant interaction between sex and revascularization strategy was observed for the primary end point (pint=0.012) and all-cause death (pint=0.037). Among women, compared with percutaneous coronary intervention, coronary artery bypass grafting was associated with lower risk of the primary end point (event rate 9.5% versus 15.3%; adjusted hazard ratio [AHR], 0.53; 95% CI, 0.35-0.79, P<0.001) and all-cause death (event rate 5.6% versus 11.7% AHR, 0.50; 95% CI, 0.30-0.82) and no significant differences were observed in men. Conclusions In women undergoing coronary revascularization for unprotected left main coronary artery disease, coronary artery bypass grafting was associated with lower risk of death, myocardial infarction, or cerebrovascular accidents whereas no significant differences between coronary artery bypass grafting and percutaneous coronary intervention were observed in men. Further dedicated studies are needed to determine the optimal revascularization strategy in women with unprotected left main coronary artery disease.

Activation of the innate immune response and organ injury after cardiac surgery: a systematic review and meta-analysis of randomised trials and analysis of individual patient data from randomised and non-randomised studies.

BACKGROUND: It is unclear whether the innate immune response represents a therapeutic target for organ protection strategies in cardiac surgery. METHODS: A systematic review of trials of interventions targeting the inflammatory response to cardiac surgery reporting treatment effects on both innate immune system cytokines and organ injury was performed. The protocol was registered at the International Prospective Register of Systematic Reviews: CRD42020187239. Searches of the Cochrane Central Register of Controlled Trials, MEDLINE, and Embase were performed. Random-effects meta-analyses were used for the primary analysis. A separate analysis of individual patient data from six studies (n=785) explored sources of heterogeneity for treatment effects on cytokine levels. RESULTS: Searches to May 2020 identified 251 trials evaluating 24 interventions with 20 582 participants for inclusion. Most trials had important limitations. Methodological limitations of the included trials and heterogeneity of the treatment effects on cytokine levels between trials limited interpretation. The primary analysis demonstrated inconsistency in the direction of the treatment effects on innate immunity and organ failure or death between interventions. Analyses restricted to important subgroups or trials with fewer limitations showed similar results. Meta-regression, pooling available data from all trials, demonstrated no association between the direction of the treatment effects on inflammatory cytokines and organ injury or death. The analysis of individual patient data demonstrated heterogeneity in the association between the cytokine response and organ injury after cardiac surgery for people >75 yr old and those with some chronic diseases. CONCLUSIONS: The certainty of the evidence for a causal relationship between innate immune system activation and organ injury after cardiac surgery is low.

Junctophilin-2 tethers T-tubules and recruits functional L-type calcium channels to lipid rafts in adult cardiomyocytes.

AIM: In cardiomyocytes, transverse tubules (T-tubules) associate with the sarcoplasmic reticulum (SR), forming junctional membrane complexes (JMCs) where L-type calcium channels (LTCCs) are juxtaposed to Ryanodine receptors (RyR). Junctophilin-2 (JPH2) supports the assembly of JMCs by tethering T-tubules to the SR membrane. T-tubule remodelling in cardiac diseases is associated with downregulation of JPH2 expression suggesting that JPH2 plays a crucial role in T-tubule stability. Furthermore, increasing evidence indicate that JPH2 might additionally act as a modulator of calcium signalling by directly regulating RyR and LTCCs. This study aimed at determining whether JPH2 overexpression restores normal T-tubule structure and LTCC function in cultured cardiomyocytes. METHODS AND RESULTS: Rat ventricular myocytes kept in culture for 4 days showed extensive T-tubule remodelling with impaired JPH2 localization and relocation of the scaffolding protein Caveolin3 (Cav3) from the T-tubules to the outer membrane. Overexpression of JPH2 restored T-tubule structure and Cav3 relocation. Depletion of membrane cholesterol by chronic treatment with methyl-ß-cyclodextrin (MßCD) countered the stabilizing effect of JPH2 overexpression on T-tubules and Cav3. Super-resolution scanning patch-clamp showed that JPH2 overexpression greatly increased the number of functional LTCCs at the plasma membrane. Treatment with MßCD reduced LTCC open probability and activity. Proximity ligation assays showed that MßCD did not affect JPH2 interaction with RyR and the pore-forming LTCC subunit Cav1.2, but strongly impaired JPH2 association with Cav3 and the accessory LTCC subunit Cavß2. CONCLUSIONS: JPH2 promotes T-tubule structural stability and recruits functional LTCCs to the membrane, most likely by directly binding to the channel. Cholesterol is involved in the binding of JPH2 to T-tubules as well as in the modulation of LTCC activity. We propose a model where cholesterol and Cav3 support the assembly of lipid rafts which provide an anchor for JPH2 to form JMCs and a platform for signalling complexes to regulate LTCC activity.

Interaction of the Joining Region in Junctophilin-2 With the L-Type Ca2+ Channel Is Pivotal for Cardiac Dyad Assembly and Intracellular Ca2+ Dynamics.

RATIONALE: Ca2+-induced Ca2+ release (CICR) in normal hearts requires close approximation of L-type calcium channels (LTCCs) within the transverse tubules (T-tubules) and RyR (ryanodine receptors) within the junctional sarcoplasmic reticulum. CICR is disrupted in cardiac hypertrophy and heart failure, which is associated with loss of T-tubules and disruption of cardiac dyads. In these conditions, LTCCs are redistributed from the T-tubules to disrupt CICR. The molecular mechanism responsible for LTCCs recruitment to and from the T-tubules is not well known. JPH (junctophilin) 2 enables close association between T-tubules and the junctional sarcoplasmic reticulum to ensure efficient CICR. JPH2 has a so-called joining region that is located near domains that interact with T-tubular plasma membrane, where LTCCs are housed. The idea that this joining region directly interacts with LTCCs and contributes to LTCC recruitment to T-tubules is unknown. OBJECTIVE: To determine if the joining region in JPH2 recruits LTCCs to T-tubules through direct molecular interaction in cardiomyocytes to enable efficient CICR. METHODS AND RESULTS: Modified abundance of JPH2 and redistribution of LTCC were studied in left ventricular hypertrophy in vivo and in cultured adult feline and rat ventricular myocytes. Protein-protein interaction studies showed that the joining region in JPH2 interacts with LTCC-α1C subunit and causes LTCCs distribution to the dyads, where they colocalize with RyRs. A JPH2 with induced mutations in the joining region (mutPG1JPH2) caused T-tubule remodeling and dyad loss, showing that an interaction between LTCC and JPH2 is crucial for T-tubule stabilization. mutPG1JPH2 caused asynchronous Ca2+-release with impaired excitation-contraction coupling after ß-adrenergic stimulation. The disturbed Ca2+ regulation in mutPG1JPH2 overexpressing myocytes caused calcium/calmodulin-dependent kinase II activation and altered myocyte bioenergetics. CONCLUSIONS: The interaction between LTCC and the joining region in JPH2 facilitates dyad assembly and maintains normal CICR in cardiomyocytes.

Surgical treatment of isolated tricuspid valve infective endocarditis: 25-year results from a multicenter registry.

BACKGROUND: To assess early and late mortality in patients with isolated acute tricuspid valve infective endocarditis (TVIE) using data from a multicenter registry. METHODS: From 1983 to 2018, isolated acute TVIE was surgically treated in 157 (3.8%) patients [mean age 47 ±â€¯16 years (range 15-86 years), 25% females]. Of these, 142 (90%) had native tricuspid regurgitation, 7 (5%) native tricuspid valve (TV) steno-regurgitation, and 8 (5%) prosthetic TVIE. Intravenous drug use (IVDU) was recorded in 38% of patients, infection involved cardiac implantable electronic device leads in 21%, and vascular catheters for dialysis in 1%; in the remaining cases, the cause was unknown. The primary endpoint was in-hospital outcome, long-term freedom from recurrence and overall survival. RESULTS: Overall, 77 (49%) patients underwent TV repair, 72 (46%) TV replacement, and 8 (5%) prosthetic TV replacement. Early mortality was 11% (n = 17). Expected early mortality according to EndoSCORE was 12%, with age (odds ratio 1.06) and redo (odds ratio 6.64) as risk factors. Late deaths occurred in 31 patients and TVIE recurrences in 4. Survival rates at 10, 20, and 25 years were 66%, 60%, and 44%, respectively. Risk factors were age [hazard ratio (HR) 1.06], mycotic TVIE (HR 4.2), IVDU (HR 4.90), infected prosthesis replacement (HR 4.4), and presence of cardiac implantable electronic device leads (HR 3.0). No significant difference was found in valve repair vs. replacement and in IVDUs vs. non-IVDUs. CONCLUSIONS: Patients with isolated acute TVIE undergoing surgical treatment show acceptable early and late outcomes. TVIE recurrence was low, and repair of the affected valve does not seem to confer any advantage either at early or long term up to 25 years.

The K219T-Lamin mutation induces conduction defects through epigenetic inhibition of SCN5A in human cardiac laminopathy.

Mutations in LMNA, which encodes the nuclear proteins Lamin A/C, can cause cardiomyopathy and conduction disorders. Here, we employ induced pluripotent stem cells (iPSCs) generated from human cells carrying heterozygous K219T mutation on LMNA to develop a disease model. Cardiomyocytes differentiated from these iPSCs, and which thus carry K219T-LMNA, have altered action potential, reduced peak sodium current and diminished conduction velocity. Moreover, they have significantly downregulated Nav1.5 channel expression and increased binding of Lamin A/C to the promoter of SCN5A, the channel's gene. Coherently, binding of the Polycomb Repressive Complex 2 (PRC2) protein SUZ12 and deposition of the repressive histone mark H3K27me3 are increased at SCN5A. CRISPR/Cas9-mediated correction of the mutation re-establishes sodium current density and SCN5A expression. Thus, K219T-LMNA cooperates with PRC2 in downregulating SCN5A, leading to decreased sodium current density and slower conduction velocity. This mechanism may underlie the conduction abnormalities associated with LMNA-cardiomyopathy.

Partial Mechanical Unloading of the Heart Disrupts L-Type Calcium Channel and Beta-Adrenoceptor Signaling Microdomains.

Introduction: We investigated the effect of partial mechanical unloading (PMU) of the heart on the physiology of calcium and beta-adrenoceptor-cAMP (ßAR-cAMP) microdomains. Previous studies have investigated PMU using a model of heterotopic-heart and lung transplantation (HTHAL). These studies have demonstrated that PMU disrupts the structure of cardiomyocytes and calcium handling. We sought to understand these processes by studying L-Type Calcium Channel (LTCC) activity and sub-type-specific ßAR-cAMP signaling within cardiomyocyte membrane microdomains. Method: We utilized an 8-week model of HTHAL, whereby the hearts of syngeneic Lewis rats were transplanted into the abdomens of randomly assigned cage mates. A pronounced atrophy was observed in hearts after HTHAL. Cardiomyocytes were isolated via enzymatic perfusion. We utilized Förster Resonance Energy Transfer (FRET) based cAMP-biosensors and scanning ion conductance microscopy (SICM) based methodologies to study localization of LTCC and ßAR-cAMP signaling. Results: ß2AR-cAMP responses measured by FRET in the cardiomyocyte cytosol were reduced by PMU (loaded 28.51 ± 7.18% vs. unloaded 10.84 ± 3.27% N,n 4/10-13 mean ± SEM ∗ p < 0.05). There was no effect of PMU on ß2AR-cAMP signaling in RII_Protein Kinase A domains. ß1AR-cAMP was unaffected by PMU in either microdomain. Consistent with this SICM/FRET analysis demonstrated that ß2AR-cAMP was specifically reduced in t-tubules (TTs) after PMU (loaded TT 0.721 ± 0.106% vs. loaded crest 0.104 ± 0.062%, unloaded TT 0.112 ± 0.072% vs. unloaded crest 0.219 ± 0.084% N,n 5/6-9 mean ± SEM ∗∗ p < 0.01, ∗∗∗ p < 0.001 vs. loaded TT). By comparison ß1AR-cAMP responses in either TT or sarcolemmal crests were unaffected by the PMU. LTCC occurrence and open probability (Po) were reduced by PMU (loaded TT Po 0.073 ± 0.011% vs. loaded crest Po 0.027 ± 0.006% N,n 5/18-26 mean ± SEM ∗ p < 0.05) (unloaded TT 0.0350 ± 0.003% vs. unloaded crest Po 0.025 N,n 5/20-30 mean ± SEM NS # p < 0.05 unloaded vs. loaded TT). We discovered that PMU had reduced the association between Caveolin-3, Junctophilin-2, and Cav1.2. Discussion: PMU suppresses' ß2AR-cAMP and LTCC activity. When activated, the signaling of ß2AR-cAMP and LTCC become more far-reaching after PMU. We suggest that a situation of 'suppression/decompartmentation' is elicited by the loss of refined cardiomyocyte structure following PMU. As PMU is a component of modern device therapy for heart failure this study has clinical ramifications and raises important questions for regenerative medicine.

Cardiomyocyte Membrane Structure and cAMP Compartmentation Produce Anatomical Variation in ß2AR-cAMP Responsiveness in Murine Hearts.

Cardiomyocytes from the apex but not the base of the heart increase their contractility in response to ß2-adrenoceptor (ß2AR) stimulation, which may underlie the development of Takotsubo cardiomyopathy. However, both cell types produce comparable cytosolic amounts of the second messenger cAMP. We investigated this discrepancy using nanoscale imaging techniques and found that, structurally, basal cardiomyocytes have more organized membranes (higher T-tubular and caveolar densities). Local membrane microdomain responses measured in isolated basal cardiomyocytes or in whole hearts revealed significantly smaller and more short-lived ß2AR/cAMP signals. Inhibition of PDE4, caveolar disruption by removing cholesterol or genetic deletion of Cav3 eliminated differences in local cAMP production and equilibrated the contractile response to ß2AR. We conclude that basal cells possess tighter control of cAMP because of a higher degree of signaling microdomain organization. This provides varying levels of nanostructural control for cAMP-mediated functional effects that orchestrate macroscopic, regional physiological differences within the heart.

Recurrent cerebral ischemia after patent foramen ovale percutaneous closure in older patients: A two-center registry study.

OBJECTIVES: The aim of this study is to describe the cerebral ischemia recurrence rate after percutaneous patent foramen ovale (PFO) closure in patients older than 55 years and their outcomes, compared with younger patients. BACKGROUND: The registries data and the recent randomized trials about PFO closure are focused on patients younger than 55 years. Little is known about older patients' long-term outcome. METHODS: In total, 458 patients underwent PFO closure for cryptogenic cerebral ischemia and were stratified into an "older" (≥ 55 years, 151 patients) and a "younger" (<55 years, 307 patients) group. RESULTS: Older patients had mean age of 63 ± 6 years and more atrial septum aneurysm (P = 0.05), hypertension, diabetes, and dyslipidemia (P = 0.001). Mean followup was 4.5 ± 2.8 years. Older patients had a higher rate of ischemic recurrence (0.3 vs. 4.0%, P = 0.002), after a mean time of 3.1 ± 2.6 years. The Kaplan-Meier curve confirmed higher event-free survival in the youngers (P = 0.008). None of the patients with ischemic recurrence had significant residual shunt. Age and hypertension were correlated to ischemic recurrence, but age was the only independent predictor at multivariate analysis. CONCLUSIONS: Recurrent cerebral ischemia after PFO closure is more frequent in older patients and could most likely be associated to conditions related to age (atherosclerosis, atrial fibrillation), than to paradoxical embolism. The procedure is as safe as in younger patients.

Paravalvular Leak Leading to Severe Aortic Valve Regurgitation after TAVI: Percutaneous Closure Strategy.

Regurgitation due to a paravalvular leak (PVL) is a complication that may affect patients undergoing surgical mechanical or bioprosthetic heart valve replacement. PVL can also occur after transcatheter aortic valve implantation (TAVI) in patients with severe aortic stenosis and is associated with significantly worse outcomes. We report a case in which different closure strategies and devices were attempted and required to percutaneously close a severe PVL after TAVI in a patient with prohibitive surgical risk.

Balancing the Risk of Bleeding and Stroke in Patients With Atrial Fibrillation After Percutaneous Coronary Intervention (from the AVIATOR Registry).

Patients with atrial fibrillation (AF) who underwent percutaneous coronary intervention (PCI) are at elevated risk for bleeding and thromboembolic ischemic events. Currently, guidelines on antithrombotic treatment for these patients are based on weak consensus. We describe patterns and determinants of antithrombotic prescriptions in this population. The Antithrombotic Strategy Variability in Atrial Fibrillation and Obstructive Coronary Disease Revascularized with PCI Registry was an international observational study of 859 consecutive patients with AF who underwent PCI from 2009 to 2011. Patients were stratified by treatment at discharge with either dual antiplatelet therapy (DAPT; aspirin plus clopidogrel) or triple therapy (TT; warfarin plus DAPT). Bleeding and thromboembolism risks were assessed by the HAS-BLED and CHADS2 scores, respectively, and predictors of TT prescription at discharge were identified. Major adverse cardiovascular events and clinically relevant bleeding (Bleeding Academic Research Consortium score ≥2) at 1-year follow-up were compared across antithrombotic regimens. Compared with patients on DAPT (n = 488; 57%), those given TT (n = 371; 43%) were older, with higher CHADS2 scores, lower left ventricular ejection fraction, and more often had permanent AF, single-vessel coronary artery disease, and bare-metal stents. In multivariate analysis, increasing thromboembolic risk (CHADS2) was associated with a higher rate of TT prescription at discharge (intermediate vs low CHADS2: odds ratio 2.2, 95% confidence interval [CI] 2.0 to 3.3, p <0.01; high vs low CHADS2: odds ratio 1.6, 95% CI 2.6 to 4.3, p <0.01 for TT). However, there was no significant association between bleeding risk and TT prescription in the overall cohort or within each CHADS2 risk stratum. The rates of major adverse cardiovascular events were similar for patients discharged on TT or DAPT (20% vs 17%, adjusted hazard ratio 0.8, 95% CI 0.5 to 1.1, p = 0.19), whereas the rate of Bleeding Academic Research Consortium ≥2 bleeding was higher in patients discharged on TT (11.5% vs 6.4%, adjusted hazard ratio 1.8, 95% CI 1.1 to 2.9, p = 0.02). In conclusion, the choice of the intensity of antithrombotic therapy correlated more closely with the risk of ischemic rather than bleeding events in this cohort of patients with AF who underwent PCI.