Re-appraisal of the obesity paradox in heart failure: a meta-analysis of individual data.

BACKGROUND: Higher body mass index (BMI) is associated with better outcome compared with normal weight in patients with HF and other chronic diseases. It remains uncertain whether the apparent protective role of obesity relates to the absence of comorbidities. Therefore, we investigated the effect of BMI on outcome in younger patients without co-morbidities as compared to older patients with co-morbidities in a large heart failure (HF) population. METHODS: In an individual patient data analysis from pooled cohorts, 5,819 patients with chronic HF and data available on BMI, co-morbidities and outcome were analysed. Patients were divided into four groups based on BMI (i.e. ≤ 18.5 kg/m2, 18.5-25.0 kg/m2; 25.0-30.0 kg/m2; 30.0 kg/m2). Primary endpoints included all-cause mortality and HF hospitalization-free survival. RESULTS: Mean age was 65 ± 12 years, with a majority of males (78%), ischaemic HF and HF with reduced ejection fraction. Frequency of all-cause mortality or HF hospitalization was significantly worse in the lowest two BMI groups as compared to the other two groups; however, this effect was only seen in patients older than 75 years or having at least one relevant co-morbidity, and not in younger patients with HF only. After including medications and N-terminal pro-B-type natriuretic peptide and high-sensitivity cardiac troponin concentrations into the model, the prognostic impact of BMI was largely absent even in the elderly group with co-morbidity. CONCLUSIONS: The present study suggests that obesity is a marker of less advanced disease, but does not have an independent protective effect in patients with chronic HF. Categories of BMI are only predictive of poor outcome in patients aged > 75 years or with at least one co-morbidity (bottom), but not in those aged < 75 years without co-morbidities (top). The prognostic effect largely disappears in multivariable analyses even for the former group. These findings question the protective effect of obesity in chronic heart failure (HF).

Mechanical dispersion as a marker of left ventricular dysfunction and prognosis in stable coronary artery disease.

Assessment of global longitudinal strain (GLS) is superior to ejection fraction (EF) in the evaluation of left ventricular (LV) function in patients with stable coronary artery disease (CAD). However, the role of mechanical dispersion (MD) in this context remains unresolved. We aimed to evaluate the potential role of MD as a marker of LV dysfunction and long-term prognosis in stable CAD. EF, GLS and MD were assessed in 160 patients with stable CAD, 1 year after successful coronary revascularization. Serum levels of high-sensitivity cardiac troponin I (hs-cTnI) and amino-terminal pro B-type natriuretic peptide (NT-proBNP) were quantified as surrogate markers of LV dysfunction. The primary endpoint was defined as all-cause mortality, the secondary endpoint was defined as the composite of all-cause mortality and hospitalization for acute myocardial infarction or heart failure during follow-up. Whereas no associations between EF and the biochemical markers of LV function were found, both GLS and MD correlated positively with increasing levels of hs-cTnI (R = 0.315, P < 0.001 and R = 0.442, P < 0.001, respectively) and NT-proBNP (R = 0.195, P = 0.016 and R = 0.390, P < 0.001, respectively). Median MD was 46 ms (interquartile range [IQR] 37-53) and was successfully quantified in 96% of the patients. During a median follow-up of 8.4 (IQR 8.2-8.8) years, 14 deaths and 29 secondary events occurred. MD was significantly increased in non-survivors, and provided incremental prognostic value when added to EF and GLS. NT-proBNP was superior to the echocardiographic markers in predicting adverse outcomes. MD may be a promising marker of LV dysfunction and adverse prognosis in stable CAD.

Revisiting the obesity paradox in heart failure: Per cent body fat as predictor of biomarkers and outcome.

AIMS: Obesity defined by body mass index (BMI) is characterized by better prognosis and lower plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) in heart failure. We assessed whether another anthropometric measure, per cent body fat (PBF), reveals different associations with outcome and heart failure biomarkers (NT-proBNP, high-sensitivity troponin T (hs-TnT), soluble suppression of tumorigenesis-2 (sST2)). METHODS: In an individual patient dataset, BMI was calculated as weight (kg)/height (m) 2 , and PBF through the Jackson-Pollock and Gallagher equations. RESULTS: Out of 6468 patients (median 68 years, 78% men, 76% ischaemic heart failure, 90% reduced ejection fraction), 24% died over 2.2 years (1.5-2.9), 17% from cardiovascular death. Median PBF was 26.9% (22.4-33.0%) with the Jackson-Pollock equation, and 28.0% (23.8-33.5%) with the Gallagher equation, with an extremely strong correlation (r = 0.996, p < 0.001). Patients in the first PBF tertile had the worst prognosis, while patients in the second and third tertile had similar survival. The risks of all-cause and cardiovascular death decreased by up to 36% and 27%, respectively, per each doubling of PBF. Furthermore, prognosis was better in the second or third PBF tertiles than in the first tertile regardless of model variables. Both BMI and PBF were inverse predictors of NT-proBNP, but not hs-TnT. In obese patients (BMI ≥ 30 kg/m2, third PBF tertile), hs-TnT and sST2, but not NT-proBNP, independently predicted outcome. CONCLUSION: In parallel with increasing BMI or PBF there is an improvement in patient prognosis and a decrease in NT-proBNP, but not hs-TnT or sST2. hs-TnT or sST2 are stronger predictors of outcome than NT-proBNP among obese patients.

High-sensitivity troponin T, NT-proBNP and glomerular filtration rate: A multimarker strategy for risk stratification in chronic heart failure.

BACKGROUND: In a recent individual patient data meta-analysis, high-sensitivity troponin T (hs-TnT) emerged as robust predictor of prognosis in stable chronic heart failure (HF). In the same population, we compared the relative predictive performances of hs-TnT, N-terminal fraction of pro-B-type natriuretic peptide (NT-proBNP), hs-C-reactive protein (hs-CRP), and estimated glomerular filtration rate (eGFR) for prognosis. METHODS AND RESULTS: 9289 patients (66 ±â€¯12 years, 77% men, 85% LVEF <40%, 60% ischemic HF) were evaluated over a 2.4-year median follow-up. Median eGFR was 58 mL/min/1.73 m2 (interquartile interval 46-70; n = 9220), hs-TnT 16 ng/L (8-20; n = 9289), NT-proBNP 1067 ng/L (433-2470; n = 8845), and hs-CRP 3.3 mg/L (1.4-7.8; n = 7083). In a model including all 3 biomarkers, only hs-TnT and NT-proBNP were independent predictors of all-cause and cardiovascular mortality and cardiovascular hospitalization. hs-TnT was a stronger predictor than NT-proBNP: for example, the risk for all-cause death increased by 54% per doubling of hs-TnT vs. 24% per doubling of NT-proBNP. eGFR showed independent prognostic value from both hs-TnT and NT-proBNP. The best hs-TnT and NT-proBNP cut-offs for the prediction of all-cause death increased progressively with declining renal function (eGFR ≥ 90: hs-TnT 13 ng/L and NT-proBNP 825 ng/L; eGFR < 30: hs-TnT 40 ng/L and NT-proBNP 4608 ng/L). Patient categorization according to these cut-offs effectively stratified patient prognosis across all eGFR classes. CONCLUSIONS: hs-TnT conveys independent prognostic information from NT-proBNP, while hs-CRP does not. Concomitant assessment of eGFR may further refine risk stratification. Patient classification according to hs-TnT and NT-proBNP cut-offs specific for the eGFR classes holds prognostic significance.

sST2 Predicts Outcome in Chronic Heart Failure Beyond NT-proBNP and High-Sensitivity Troponin T.

BACKGROUND: Soluble suppression of tumorigenesis-2 (sST2) is a biomarker related to inflammation and fibrosis. OBJECTIVES: This study assessed the independent prognostic value of sST2 in chronic heart failure (HF). METHODS: Individual patient data from studies that assessed sST2 for risk prediction in chronic HF, together with N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity troponin T (hs-TnT), were retrieved. RESULTS: A total of 4,268 patients were evaluated (median age 68 years, 75% males, 65% with ischemic HF, 87% with left ventricular ejection fraction [LVEF] <40%). NT-proBNP, hs-TnT, and sST2 were 1,360 ng/l (interquartile interval: 513 to 3,222 ng/l), 18 ng/l (interquartile interval: 9 to 33 ng/l), and 27 ng/l (interquartile interval: 20 to 39 ng/l), respectively. During a 2.4-year median follow-up, 1,319 patients (31%) experienced all-cause death (n = 932 [22%] for cardiovascular causes). Among the 4,118 patients (96%) with available data, 1,029 (24%) were hospitalized at least once for worsening HF over 2.2 years. The best sST2 cutoff for the prediction of all-cause and cardiovascular death and HF hospitalization was 28 ng/ml, with good performance at Kaplan-Meier analysis (log-rank: 117.6, 61.0, and 88.6, respectively; all p < 0.001). In a model that included age, sex, body mass index, ischemic etiology, LVEF, New York Heart Association functional class, glomerular filtration rate, HF medical therapy, NT-proBNP, and hs-TnT, the risk of all-cause death, cardiovascular death, and HF hospitalization increased by 26%, 25%, and 30%, respectively, per each doubling of sST2. sST2 retained its independent prognostic value across most population subgroups. CONCLUSIONS: sST2 yielded strong, independent predictive value for all-cause and cardiovascular mortality, and HF hospitalization in chronic HF, and deserves consideration to be part of a multimarker panel together with NT-proBNP and hs-TnT.

Prognostic Value of High-Sensitivity Troponin T in Chronic Heart Failure: An Individual Patient Data Meta-Analysis.

BACKGROUND: Most patients with chronic heart failure have detectable troponin concentrations when evaluated by high-sensitivity assays. The prognostic relevance of this finding has not been clearly established so far. We aimed to assess high-sensitivity troponin assay for risk stratification in chronic heart failure through a meta-analysis approach. METHODS: Medline, EMBASE, Cochrane Library, and Scopus were searched in April 2017 by 2 independent authors. The terms were "troponin" AND "heart failure" OR "cardiac failure" OR "cardiac dysfunction" OR "cardiac insufficiency" OR "left ventricular dysfunction." Inclusion criteria were English language, clinical stability, use of a high-sensitivity troponin assay, follow-up studies, and availability of individual patient data after request to authors. Data retrieved from articles and provided by authors were used in agreement with the PRISMA statement. The end points were all-cause death, cardiovascular death, and hospitalization for cardiovascular cause. RESULTS: Ten studies were included, reporting data on 11 cohorts and 9289 patients (age 66±12 years, 77% men, 60% ischemic heart failure, 85% with left ventricular ejection fraction <40%). High-sensitivity troponin T data were available for all patients, whereas only 209 patients also had high-sensitivity troponin I assayed. When added to a prognostic model including established risk markers (sex, age, ischemic versus nonischemic etiology, left ventricular ejection fraction, estimated glomerular filtration rate, and N-terminal fraction of pro-B-type natriuretic peptide), high-sensitivity troponin T remained independently associated with all-cause mortality (hazard ratio, 1.48; 95% confidence interval, 1.41-1.55), cardiovascular mortality (hazard ratio, 1.40; 95% confidence interval, 1.33-1.48), and cardiovascular hospitalization (hazard ratio, 1.42; 95% confidence interval, 1.36-1.49), over a median 2.4-year follow-up (all P<0.001). High-sensitivity troponin T significantly improved risk prediction when added to a prognostic model including the variables above. It also displayed an independent prognostic value for all outcomes in almost all population subgroups. The area under the curve-derived 18 ng/L cutoff yielded independent prognostic value for the 3 end points in both men and women, patients with either ischemic or nonischemic etiology, and across categories of renal dysfunction. CONCLUSIONS: In chronic heart failure, high-sensitivity troponin T is a strong and independent predictor of all-cause and cardiovascular mortality, and of hospitalization for cardiovascular causes, as well. This biomarker then represents an additional tool for prognostic stratification.

Troponinas de alta sensibilidad T vs I en Sindrome Coronario Agudo: Predicción de lesiones coronarias significativas y pronóstico a largo plazo / High-Sensitivity Troponin T vs I in Acute Coronary Syndrome: Prediction of Significant Coronary Lesions and Long-term Prognosis

Antecedentes: Los ensayos de troponinas cardíacas de alta sensibilidad (hs-cTn) tanto T e I son una herramienta crucial y bien establecida para el diagnóstico de infarto agudo de miocardio (IAM), ya que se ha demostrado ampliamente su superioridad respecto a las antiguas determinaciones de troponina. Sin embargo, eventuales diferencias entre ambos ensayos en la predicción de lesiones coronarias significativas y el pronóstico a largo plazo en pacientes con síndrome coronario agudo (SCA) no han sido aclarados completamente. Métodos: Se evaluaron las concentraciones séricas de hs-cTnT (Roche), hs-cTnI (Abbott) y porción amino-terminal del pro-péptido natriurético tipo B (NT-proBNP) (Roche) en 390 pacientes con SCA sin elevación del segmento ST, y se relacionaron con lesiones coronarias significativas detectadas por angiografía coronaria (definidas como estenosis >50% del diámetro luminal, con necesidad de revascularización) y con la precisión pronóstica de mortalidad cardiovascular, mortalidad por cualquier causa, así como también con el punto final compuesto por mortalidad cardiovascular y hospitalizaciones por IAM o insuficiencia cardiaca. Resultados: La media (+DE) del seguimiento fue de 2921+168 días. Las concentraciones absolutas de hs-cTnI fueron significativamente mayores que las concentraciones de hs-cTnT. La relación entre los biomarcadores analizados y lesiones coronarias significativas en angiografía coronaria, cuantificada por el área bajo la curva ROC (AUC), no reveló diferencias entre hs-cTnT [AUC, 0,81; IC del 95%, 0,77- 0,86] y hs-cTnI (AUC, 0,81; IC del 95%, 0,76-0,86; P=NS). Sin embargo, NT-proBNP fue superior a ambos ensayos de hs-cTn en relación con la precisión pronóstica tanto para mortalidad cardiovascular y por cualquier causa, como para el punto final compuesto durante el seguimiento, aún también en análisis multivariados. Conclusiones: Los determinaciones de hs-cTnT y hs-cTnI mostraron una capacidad similar para predecir lesiones coronarias significativas en pacientes con SCA sin elevación del segmento ST. NT-proBNP fue superior a ambos ensayos de uscTn, como marcador de pronóstico a largo plazo en este grupo de pacientes.

Background: High-sensitivity cardiac troponin (hs-cTn) T and I assays are established as crucial tools for the diagnosis of acute myocardial infarction (AMI), as they have been found superior to old troponin assays. However, eventual differences between the assays in prediction of significant coronary lesions and long-term prognosis in patients with acute coronary syndrome (ACS) have not been fully unraveled. Methods: Serum concentrations of hs-cTnT (Roche), hs-cTnI (Abbott), and amino-terminal pro-B-type natriuretic peptide (NT-proBNP; Roche) in 390 non-ST-elevation (NSTE) ACS patients were evaluated in relation to significant coronary lesions on coronary angiography (defined as a stenosis >50% of the luminal diameter, with need for revascularization) and prognostic accuracy for cardiovascular mortality, all-cause mortality, as well as the composite end point of cardiovascular mortality and hospitalizations for AMI or heart failure. Results: The mean+SD follow-up was 2921+168 days. Absolute hs-cTnI concentrations were significantly higher than the hs-cTnT concentrations. The relationship between analyzed biomarkers and significant coronary lesions on coronary angiography, as quantified by the area under the ROC curve (AUC), revealed no difference between hs-cTnT [AUC, 0.81; 95% CI, 0.77-0.86] and hs-cTnI (AUC, 0.81; 95% CI, 0.76-0.86; P=NS). NT-proBNP was superior to both hs-cTn assays regarding prognostic accuracy for both cardiovascular and all-cause mortality and for the composite end point during follow-up, also in multivariate analyses. Conclusions: The hs-cTnT and hs-cTnI assays displayed a similar ability to predict significant coronary lesions in NSTE-ACS patients. NT-proBNP was superior to both hs-cTn assays as a marker of long-term prognosis in this patient group.

Connective tissue growth factor and bone morphogenetic protein 2 are induced following myocardial ischemia in mice and humans.

We aimed to study the cardiac expression of bone morphogenetic protein 2, its receptor 1 b, and connective tissue growth factor, factors implicated in cardiac embryogenesis, following ischemia/hypoxia, heart failure, and in remodeling hearts from humans and mice. Biopsies from the left ventricle of patients with end-stage heart failure due to dilated cardiomyopathy or coronary artery disease were compared with donor hearts and biopsies from patients with normal heart function undergoing coronary artery bypass grafting. Mouse model of post-infarction remodeling was made by permanent ligation of the left coronary artery. Hearts were analyzed by real-time polymerase chain reaction and Western blotting after 24 hours and after 2 and 4 weeks. Patients with dilated cardiomyopathy and mice post-infarction had increased cardiac expression of connective tissue growth factor. Bone morphogenetic protein 2 was increased in human hearts failing due to coronary artery disease and in mice post-infarction. Gene expression of bone morphogenetic protein receptor 1 beta was reduced in hearts of patients with failure, but increased two weeks following permanent ligation of the left coronary artery in mice. In conclusion, connective tissue growth factor is upregulated in hearts of humans with dilated cardiomyopathy, bone morphogenetic protein 2 is upregulated in remodeling due to myocardial infarction while its receptor 1 b in human failing hearts is downregulated. A potential explanation might be an attempt to engage regenerative processes, which should be addressed by further, mechanistic studies.

Limited Added Value of Circulating Inflammatory Biomarkers in Chronic Heart Failure.

OBJECTIVES: This study sought to evaluate whether a panel of biomarkers improved prognostication in patients with heart failure (HF) and reduced ejection fraction of ischemic origin using a systematized approach according to suggested requirements for validation of new biomarkers. BACKGROUND: Modeling combinations of multiple circulating markers could potentially identify patients with HF at particularly high risk and aid in the selection of individualized therapy. METHODS: From a panel of 20 inflammatory and extracellular matrix biomarkers, 2 different biomarker panels were created and added to the Seattle HF score and the prognostic model from the CORONA (Controlled Rosuvastatin Multinational Trial in Heart Failure) study (n = 1,497), which included conventional clinical characteristics and C-reactive protein and N-terminal pro-B-type natriuretic peptide. Interactions with statin treatment were also assessed. RESULTS: The two models-model 1 (endostatin, interleukin 8, soluble ST2, troponin T, galectin 3, and chemokine [C-C motif] ligand 21) and model 2 (troponin T, soluble ST2, galectin 3, pentraxin 3, and soluble tumor necrosis factor receptor 2)-significantly improved the CORONA and Seattle HF models but added only modestly to their Harrell's C statistic and net reclassification index. In addition, rosuvastatin had no effect on the levels of a wide range of inflammatory and extracellular matrix markers, but there was a tendency for patients with a lower level of biomarkers in the 2 panels to have a positive effect from statin treatment. CONCLUSIONS: In the specific HF patient population studied, a multimarker approach using the particular panel of biomarkers measured was of limited clinical value for identifying future risk of adverse outcomes.

High-Sensitivity Troponin T vs I in Acute Coronary Syndrome: Prediction of Significant Coronary Lesions and Long-term Prognosis.

BACKGROUND: High-sensitivity cardiac troponin (hs-cTn) T and I assays are established as crucial tools for the diagnosis of acute myocardial infarction (AMI), as they have been found superior to old troponin assays. However, eventual differences between the assays in prediction of significant coronary lesions and long-term prognosis in patients with acute coronary syndrome (ACS) have not been fully unraveled. METHODS: Serum concentrations of hs-cTnT (Roche), hs-cTnI (Abbott), and amino-terminal pro-B-type natriuretic peptide (NT-proBNP; Roche) in 390 non-ST-elevation (NSTE) ACS patients were evaluated in relation to significant coronary lesions on coronary angiography (defined as a stenosis >50% of the luminal diameter, with need for revascularization) and prognostic accuracy for cardiovascular mortality, all-cause mortality, as well as the composite end point of cardiovascular mortality and hospitalizations for AMI or heart failure. RESULTS: The mean (SD) follow-up was 2921 (168) days. Absolute hs-cTnI concentrations were significantly higher than the hs-cTnT concentrations. The relationship between analyzed biomarkers and significant coronary lesions on coronary angiography, as quantified by the area under the ROC curve (AUC), revealed no difference between hs-cTnT [AUC, 0.81; 95% CI, 0.77-0.86] and hs-cTnI (AUC, 0.81; 95% CI, 0.76-0.86; P = NS). NT-proBNP was superior to both hs-cTn assays regarding prognostic accuracy for both cardiovascular and all-cause mortality and for the composite end point during follow-up, also in multivariate analyses. CONCLUSIONS: The hs-cTnT and hs-cTnI assays displayed a similar ability to predict significant coronary lesions in NSTE-ACS patients. NT-proBNP was superior to both hs-cTn assays as a marker of long-term prognosis in this patient group.

Sensitive cardiac troponins and N-terminal pro-B-type natriuretic peptide in stable coronary artery disease: correlation with left ventricular function as assessed by myocardial strain.

N-terminal pro-B-type natriuretic peptide (NT-proBNP) and cardiac troponins (cTns) measured with sensitive assays provide strong prognostic information in patients with stable coronary artery disease. However, the relationship between these biomarkers and myocardial contractile function, as well as infarct size, in this patient group, remains to be defined. The study population consisted of 160 patients referred to a follow-up echocardiography scheduled 1 year after coronary revascularization. Concentrations of NT-proBNP, high-sensitive cTnT (hs-cTnT) and sensitive cTnI assays were assessed. Left ventricular function was measured as global peak systolic longitudinal strain by speckle tracking echocardiography and infarct size was assessed by late-enhancement MRI. NT-proBNP and sensitive cTnI levels were significantly associated with left ventricular function by peak systolic strain (R-values 0.243 and 0.228, p = 0.002 and 0.004) as well as infarct size (R-values 0.343 and 0.366, p = 0.014 and p = 0.008). In contrast, hs-cTnT did not correlate with left ventricular function (R = 0.095, p = 0.231) and only marginally with infarct size (R = 0.237, p = 0.094). NT-proBNP and sensitive cTnI levels correlate with left ventricular function and infarct size in patients with stable coronary artery disease after revascularization. As opposed to hs-cTnT, NT-proBNP and cTnI seem to be indicators of incipient myocardial dysfunction and the extent of myocardial necrosis.

Prognostic effect of high-sensitive troponin T assessment in elderly patients with chronic heart failure: results from the CORONA trial.

BACKGROUND: The incremental prognostic value of high-sensitive troponin T (hs-cTnT) in heart failure (HF) beyond that of high-sensitivity C-reactive protein and amino-terminal probrain natriuretic peptide is debated. We examined the prognostic value of hs-cTnT in a subgroup of patients from the Controlled Rosuvastatin Multinational Trial in HF (CORONA) study. METHODS AND RESULTS: Hs-cTnT as a risk factor for the primary end point (cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke; n=356), as well as all-cause mortality (n=366), cardiovascular mortality (n=299), and the composite of cardiovascular mortality and hospitalization from worsening of HF (n=465), was investigated in 1245 patients (≥60 years; New York Heart Association [NYHA] class II-IV, ischemic systolic HF) randomly assigned to 10 mg rosuvastatin or placebo. In multivariable analyses, adjusting for left ventricular ejection fraction, NYHA class, age, body mass index, diabetes mellitus, sex, intermittent claudication, heart rate, estimated glomerular filtration rate, apolipoprotein B/apolipoprotein A-1 ratio, amino-terminal probrain natriuretic peptide, high-sensitivity C-reactive protein, and hs-cTnT (both dichotomized according to the 99th percentile and as a continuous variable) was associated with all end points (primary end point: hazard ratio, 1.87 and 1.51, respectively, per SD change; P<0.001; all other end points: hazard ratio, 1.39-1.70). However, improved discrimination as assessed by C-statistics was only seen for the primary end point and all-cause mortality. CONCLUSIONS: Elevated hs-cTnT levels provide strong and independent prognostic information in older patients with chronic ischemic HF. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00206310.

Connective tissue growth factor/CCN2 attenuates ß-adrenergic receptor responsiveness and cardiotoxicity by induction of G protein-coupled receptor kinase-5 in cardiomyocytes.

Myocardial connective tissue growth factor (CTGF/CCN2) is induced in heart failure, a condition associated with diminution of ß-adrenergic receptor (ß-AR) responsiveness. Accordingly, we aimed to investigate whether CTGF could play a mechanistic role in regulation of ß-AR responsiveness. Concentration-response curves of isoproterenol-stimulated cAMP generation in cardiomyocytes from transgenic mice with cardiac-restricted overexpression of CTGF (Tg-CTGF) or cardiomyocytes pretreated with recombinant human CTGF (rec-hCTGF) revealed marked reduction of both ß1-AR and ß2-AR responsiveness. Consistently, ventricular muscle strips from Tg-CTGF mice stimulated with isoproterenol displayed attenuation of maximal inotropic responses. However, no differences of maximal inotropic responses of myocardial fibers from Tg-CTGF mice and nontransgenic littermate control (NLC) mice were discerned when stimulated with supramaximal concentrations of dibutyryl-cAMP, indicating preserved downstream responsiveness to cAMP. Congruent with a mechanism of desensitization of ß-ARs, mRNA and protein levels of G protein-coupled receptor kinase 5 (GRK5) were found isoform-selective upregulated in both cardiomyocytes from Tg-CTGF mice and cardiomyocytes exposed to rec-hCTGF. Corroborating a mechanism of GRK5 in CTGF-mediated control of ß-AR sensitivity, Chinese hamster ovary cells pretreated with rec-hCTGF displayed increased agonist- and biased ligand-stimulated ß-arrestin binding to ß-ARs. Despite increased sensitivity of cardiomyocytes from GRK5-knockout (KO) mice to ß-adrenergic agonists, pretreatment of GRK5-KO cardiomyocytes with rec-hCTGF, as opposed to cardiomyocytes from wild-type mice, did not alter ß-AR responsiveness. Finally, Tg-CTGF mice subjected to chronic exposure (14 days) to isoproterenol revealed blunted myocardial hypertrophy and preserved cardiac function versus NLC mice. In conclusion, this study uncovers a novel mechanism controlling ß-AR responsiveness in cardiomyocytes involving CTGF-mediated regulation of GRK5.

Sensitive troponin assays and N-terminal pro-B-type natriuretic peptide in acute coronary syndrome: prediction of significant coronary lesions and long-term prognosis.

BACKGROUND: Sensitive troponin assays have substantially improved early diagnosis of myocardial infarction. However, the role of sensitive cardiac troponin (cTn) assays in prediction of significant coronary lesions and long-term prognosis in non-ST-elevation acute coronary syndrome (NSTE-ACS) remains unresolved. METHODS: This prospective study includes 458 consecutive patients with NSTE-ACS admitted for coronary angiography. Serum levels of 4 commercial available sensitive troponin assays were analyzed (Roche high-sensitive cTnT [hs-cTnT; Roche Diagnostics, Basel, Switzerland], Siemens cTnI Ultra [Siemens, Munich, Germany], Abbott-Architect cTnI [Abbott, Abbott Park, IL], Access Accu-cTnI [Beckman Coulter, Nyon, Switzerland]), as well as a standard assay (Roche cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP), before coronary angiography. RESULTS: The relationship between the analyzed biomarkers and significant coronary lesions on coronary angiography, as quantified by area under the receiver operating characteristic curve, was significantly higher with Roche hs-cTnT, Siemens cTnI Ultra, and Access Accu-cTnI as compared with standard troponin T assay (P < .001 for all comparisons). This difference was mainly caused by increased sensitivity below the 99th percentile. Also, NT-proBNP was associated with the presence of significant coronary lesions. Cardiac troponin values were correlated with cardiac death (primary end point) during 1373 (1257-1478) days of follow-up. In both univariate and multivariate Cox regression analyses, NT-proBNP was superior to both hs-cTnT and cTnI in prediction of cardiovascular mortality. Troponin values with all assays were correlated with the need for repeated revascularization (secondary end point) during follow-up. CONCLUSIONS: Sensitive cTn assays are superior to standard cTnT assay in prediction of significant coronary lesions in patients with NSTE-ACS. However, this improvement is primary caused by increased sensitivity below the 99th percentile. N-terminal pro-B-type natriuretic peptide is superior to cTns in prediction of long-term mortality.

CCN2/CTGF attenuates myocardial hypertrophy and cardiac dysfunction upon chronic pressure-overload.

BACKGROUND: Myocardial CCN2/CTGF (connective tissue growth factor) is strongly induced in heart failure (HF) and acts as a cardioprotective factor in ischemia/reperfusion injury. However, its functional role in myocardial hypertrophy remains unresolved. METHODS AND RESULTS: Transgenic mice with cardiac-restricted overexpression of CTGF (Tg-CTGF) and non-transgenic littermate control (NLC) mice were subjected to chronic pressure-overload by abdominal aortic banding. After 4weeks of persistent pressure-overload, a time point at which compensatory hypertrophy of the left ventricle (LV) prevails, Tg-CTGF mice displayed diminished increase of LV mass compared with NLC. At study end-point after 12 weeks of sustained aortic constriction, the mice displayed LV dilatation and reduced cardiac function. Repeated transthoracic echocardiography during the 12 weeks of chronic pressure-overload, revealed attenuation of LV dilatation and virtually sustained systolic function in Tg-CTGF mice compared with NLC mice. Also, increase of LV mass was blunted in Tg-CTGF versus NLC mice at study end-point. Consistently, increases of myocardial ANP, BNP and skeletal α-actin mRNA levels were blunted in Tg-CTGF mice subjected to chronic pressure-overload. Furthermore, cardiac myocytes from Tg-CTGF mice displayed increased phospho-NFATc2 levels and attenuated hypertrophic response upon stimulation with α1-adrenoceptor agonist, indicating that CTGF attenuates hypertrophic signaling in cardiac myocytes. Increase of myocardial collagen contents in mice subjected to aortic banding was similar in Tg-CTGF and NLC mice, indicating that CTGF have minimal impact on myocardial collagen deposition. CONCLUSION: This study provides novel evidence that CTGF attenuates cardiac hypertrophy upon chronic pressure-overload due to inhibition of signaling mechanisms that promote pathologic myocardial hypertrophy.

Soluble glycoprotein 130 predicts fatal outcomes in chronic heart failure: analysis from the Controlled Rosuvastatin Multinational Trial in Heart Failure (CORONA).

BACKGROUND: Glycoprotein 130 (gp130) is the common signal-transducing receptor subunit of the interleukin-6 (IL-6) family, which may be involved in the progression of heart failure (HF). We hypothesized that soluble gp130 would provide prognostic information beyond that of IL-6 in a population with HF from the Controlled Rosuvastatin Multinational Trial in Heart Failure (CORONA). METHODS AND RESULTS: The associations of soluble gp130 and IL-6 with morbidity, mortality, and mode of death were assessed by immunoassays in a subset of 1452 patients enrolled in the CORONA trial, which included patients with HF, aged ≥60 years, in New York Heart Association classes II to IV, who had ischemic heart disease and a reduced left ventricular ejection fraction. In multivariable analyses, including C-reactive protein, IL-6, troponin T, and N-terminal pro-B-type natriuretic peptide, elevated soluble gp130 (fifth quintile versus all lower quintiles) was associated with all-cause mortality (hazard ratio, 1.47 [1.11-1.93]; P=0.006), cardiovascular mortality (hazard ratio, 1.38 [1.01-1.87]; P=0.042), and death from worsening HF (hazard ratio, 1.85 [1.09-3.14]; P=0.002), but not with the primary end point (composite of death from cardiovascular causes, nonfatal myocardial infarction, and nonfatal stroke; hazard ratio, 1.12 [0.84-1.50]; P=0.44). Plasma IL-6 was not associated with outcomes in multivariable analyses. CONCLUSIONS: Marked elevations in soluble gp130 are associated with total and cardiovascular mortality, as well as deaths from worsening HF, in elderly patients with HF of ischemic cause CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00206310.

Cardiomyocyte-restricted inhibition of G protein-coupled receptor kinase-3 attenuates cardiac dysfunction after chronic pressure overload.

Transgenic mice with cardiac-specific expression of a peptide inhibitor of G protein-coupled receptor kinase (GRK)3 [transgenic COOH-terminal GRK3 (GRK3ct) mice] display myocardial hypercontractility without hypertrophy and enhanced α(1)-adrenergic receptor signaling. A role for GRK3 in the pathogenesis of heart failure (HF) has not been investigated, but inhibition of its isozyme, GRK2, has been beneficial in several HF models. Here, we tested whether inhibition of GRK3 modulated evolving cardiac hypertrophy and dysfunction after pressure overload. Weight-matched male GRK3ct transgenic and nontransgenic littermate control (NLC) mice subjected to chronic pressure overload by abdominal aortic banding (AB) were compared with sham-operated (SH) mice. At 6 wk after AB, a significant increase of cardiac mass consistent with induction of hypertrophy was found, but no differences between GRK3ct-AB and NLC-AB mice were discerned. Simultaneous left ventricular (LV) pressure-volume analysis of electrically paced, ex vivo perfused working hearts revealed substantially reduced systolic and diastolic function in NLC-AB mice (n = 7), which was completely preserved in GRK3ct-AB mice (n = 7). An additional cohort was subjected to in vivo cardiac catheterization and LV pressure-volume analysis at 12 wk after AB. NLC-AB mice (n = 11) displayed elevated end-diastolic pressure (8.5 ± 3.1 vs. 2.9 ± 1.2 mmHg, P < 0.05), reduced cardiac output (3,448 ± 323 vs. 4,488 ± 342 µl/min, P < 0.05), and reduced dP/dt(max) and dP/dt(min) (both P < 0.05) compared with GRK3ct-AB mice (n = 16), corroborating the preserved cardiac structure and function observed in GRK3ct-AB hearts assessed ex vivo. Increased cardiac mass and myocardial mRNA expression of ß-myosin heavy chain confirmed the similar induction of cardiac hypertrophy in both AB groups, but only NLC-AB hearts displayed significantly elevated mRNA levels of brain natriuretic peptide and myocardial collagen contents as well as reduced ß(1)-adrenergic receptor responsiveness to isoproterenol, indicating increased LV wall stress and the transition to HF. Inhibition of cardiac GRK3 in mice does not alter the hypertrophic response but attenuates cardiac dysfunction and HF after chronic pressure overload.

Myocardial connective tissue growth factor (CCN2/CTGF) attenuates left ventricular remodeling after myocardial infarction.

AIMS: Myocardial CCN2/CTGF is induced in heart failure of various etiologies. However, its role in the pathophysiology of left ventricular (LV) remodeling after myocardial infarction (MI) remains unresolved. The current study explores the role of CTGF in infarct healing and LV remodeling in an animal model and in patients admitted for acute ST-elevation MI. METHODS AND RESULTS: Transgenic mice with cardiac-restricted overexpression of CTGF (Tg-CTGF) and non-transgenic littermate controls (NLC) were subjected to permanent ligation of the left anterior descending coronary artery. Despite similar infarct size (area of infarction relative to area at risk) 24 hours after ligation of the coronary artery in Tg-CTGF and NLC mice, Tg-CTGF mice disclosed smaller area of scar tissue, smaller increase of cardiac hypertrophy, and less LV dilatation and deterioration of LV function 4 weeks after MI. Tg-CTGF mice also revealed substantially reduced mortality after MI. Remote/peri-infarct tissue of Tg-CTGF mice contained reduced numbers of leucocytes, macrophages, and cells undergoing apoptosis as compared with NLC mice. In a cohort of patients with acute ST-elevation MI (n = 42) admitted to hospital for percutaneous coronary intervention (PCI) serum-CTGF levels (s-CTGF) were monitored and related to infarct size and LV function assessed by cardiac MRI. Increase in s-CTGF levels after MI was associated with reduced infarct size and improved LV ejection fraction one year after MI, as well as attenuated levels of CRP and GDF-15. CONCLUSION: Increased myocardial CTGF activities after MI are associated with attenuation of LV remodeling and improved LV function mediated by attenuation of inflammatory responses and inhibition of apoptosis.

Gene therapy with hypoxia-inducible factor 1 alpha in skeletal muscle is cardioprotective in vivo.

AIMS: Gene therapy of a peripheral organ to protect the heart is clinically attractive. The transcription factor hypoxia-inducible factor 1 alpha (HIF-1α) transactivates cardioprotective genes. We investigated if remote delivery of DNA encoding for HIF-1α is protective against myocardial ischemia-reperfusion injury in vivo. MAIN METHODS: DNA encoding for human HIF-1α was delivered to quadriceps muscles of mice. One week later myocardial infarction was induced and four weeks later its size was measured. Echocardiography and in vivo pressure-volume analysis was performed. Coronary vascularization was evaluated through plastic casting. HL-1 cells, transfected with either HIF-1α or HMOX-1 or administered bilirubin or the carbon monoxide (CO) donor CORM-2, were subjected to lipopolysacharide (LPS)-induced cell death to compare the efficacy of treatments. KEY FINDINGS: After four weeks of reperfusion post infarction, animals pretreated with HIF-1α showed reduced infarct size and left ventricular remodeling (p<0.05, respectively). Fractional shortening was preserved in mice pretreated with HIF-1α (p<0.05). Invasive hemodynamic parameters indicated preserved left ventricular function after HIF-1α (p<0.05), which also induced coronary vascularization (p<0.05). HIF-1α downstream target heme oxygenase 1 (HMOX-1) was upregulated in skeletal muscle, while serum bilirubin was increased. Transfection of HL-1 cells with HIF-1α or HMOX-1 and administration of bilirubin or CORM-2 comparably salvaged cells from lipopolysacharide (LPS)-induced cell death (all p<0.05). SIGNIFICANCE: HIF-1α gene delivery to skeletal muscle preceding myocardial ischemia reduced infarct size and postischemic remodeling accompanied by an improved cardiac function and vascularization. Similar to HIF-1α, HMOX-1, bilirubin and CO were protective against LPS-induced injury. This observation may have clinical potential.

Mechanisms of novel cardioprotective functions of CCN2/CTGF in myocardial ischemia-reperfusion injury.

CCN2/connective tissue growth factor (CTGF), a CCN family matricellular protein repressed in healthy hearts after birth, is induced in heart failure of various etiologies. Multiple cellular and biological functions have been assigned to CCN2/CTGF depending on cellular context. However, the functions and mechanisms of action of CCN2/CTGF in the heart as well as its roles in cardiac physiology and pathophysiology remain unknown. Transgenic mice with cardiac-restricted overexpression of CTGF (Tg-CTGF) were generated and compared with nontransgenic littermate control (NLC) mice. Tg-CTGF mice displayed slightly lower cardiac mass and inconspicuous increase of myocardial collagen compared with NLC mice but no evidence of contractile dysfunction. Analysis of the myocardial transcriptome by DNA microarray revealed activation of several distinct gene programs in Tg-CTGF hearts involved in cardioprotection and growth inhibition. Indeed, Tg-CTGF mice subjected to ischemia-reperfusion injury by in situ transient occlusion of the left anterior descending coronary artery in vivo displayed reduced vulnerability with markedly diminished infarct size. These findings were recapitulated in isolated hearts perfused with recombinant human (h)CTGF before the ischemia-reperfusion procedure. Consistently, Tg-CTGF hearts, as well as isolated adult cardiac myocytes exposed to recombinant hCTGF, displayed enhanced phosphorylation and activity of the Akt/p70S6 kinase/GSK-3ß salvage kinase pathway and induction of several genes with reported cardioprotective functions. Inhibition of Akt activities also prevented the cardioprotective phenotype of hearts from Tg-CTGF mice. This report provides novel evidence that CTGF confers cardioprotection by salvage phosphokinase signaling leading to inhibition of GSK-3ß activities, activation of phospho-SMAD2, and reprogramming of gene expression.