Plasma Clearance of B-Type Natriuretic Peptide (BNP) before and after Bariatric Surgery for Morbid Obesity.

BACKGROUND: Obese patients have lower plasma concentrations of the cardiac natriuretic peptides (NPs) than their age- and sex-matched counterparts. This may reflect lower production and/or increased peptide clearance. It is unclear whether NP bioactivity is affected by obesity. METHODS: We studied the effects of obesity on B-type natriuretic peptide (BNP) clearance and bioactivity by comparing results from standardized intravenous infusions of BNP administered 2 weeks before and 6 months after bariatric surgery in 12 consecutive patients with morbid obesity (body mass index, BMI > 35 kg/m2). Anthropometric, clinical, neurohormonal, renal, and echocardiographic variables were obtained pre- and postsurgery. Pre- vs postsurgery calculated intrainfusion peptide clearances were compared. RESULTS: BMI (44.3 ± 5.0 vs 33.9 ± 5.2 kg/m2, P < 0.001) and waist circumference (130.3 ± 11.9 vs 107.5 ± 14.7 cm, P < 0.001) decreased substantially after bariatric surgery. Calculated plasma clearance of BNP was reduced (approximately 30%) after surgery. Though not controlled for, sodium intake was presumably lower after bariatric surgery. Despite this, preinfusion endogenous plasma NP concentrations did not significantly differ between pre- and postsurgery studies. The ratio of plasma N-terminal (NT)-proBNP to 24 h urine sodium excretion was higher postsurgery (P = 0.046; with similar nonsignificant findings for BNP, atrial NP (ANP) and NT-proANP), indicating increased circulating NPs for a given sodium status. Mean plasma NP concentrations for given calculated end-systolic wall stress and cardiac filling pressures (as assessed by echocardiographic E/e') rose slightly, but not significantly postsurgery. Second messenger, hemodynamic, renal, and neurohormonal responses to BNP were not altered between studies. CONCLUSION: Obesity is associated with increased clearance, but preserved bioactivity, of BNP.

Atrial Fibrillation and the Prognostic Performance of Biomarkers in Heart Failure.

BACKGROUND: Consideration of circulating biomarkers for risk stratification in heart failure (HF) is recommended, but the influence of atrial fibrillation (AF) on prognostic performance of many markers is unclear. We investigated the influence of AF on the prognostic performance of circulating biomarkers in HF. METHODS: N-terminal pro-B-type natriuretic peptide (NT-proBNP), mid-regional-pro-atrial natriuretic peptide, C-type natriuretic peptide (CNP), NT-proCNP, high-sensitivity troponin-T, high-sensitivity troponin-I, mid-regional-propeptide adrenomedullin, co-peptin, growth differentiation factor-15, soluble Suppressor of Tumorigenicitiy (sST2), galectin-3, and procalcitonin plasma concentrations were measured in a prospective, multicenter study of adults with HF. AF was defined as a previous history of AF, and/or presence of AF/flutter on baseline 12-lead electrocardiogram. The primary outcome was the composite of HF-hospitalization or all-cause mortality at 2 years. RESULTS: Among 1099 patients (age 62 ± 12years, 28% female), 261(24%) patients had AF. Above-median concentrations of all biomarkers were independently associated with increased risk of the primary outcome. Significant interactions with AF were detected for galectin-3 and sST2. In considering NT-proBNP for additive risk stratification, sST2 (adjusted hazard ratio [AHR]1.85, 95%confidence interval [C.I.] 1.17-2.91) and galectin-3 (AHR1.85, 95%C.I. 1.09-2.45) were independently associated with increased primary outcome only in the presence of AF. The prognostic performance of sST2 was also stronger in AF for all-cause mortality (AF: AHR2.82, 95%C.I. 1.26-6.21; non-AF: AHR1.78, 95% C.I. 1.14-2.76 without AF), while galectin-3 predicted HF-hospitalization only in AF (AHR1.64, 95%C.I. 1.03-2.62). CONCLUSIONS: AF modified the prognostic utility of selected guideline-endorsed HF-biomarkers. Application of markers for prognostic purposes in HF requires consideration of the presence or absence of AF. CLINICAL TRIAL REGISTRATION: ACTRN12610000374066.

Ankyrin Repeat Domain 1 Protein: A Functionally Pleiotropic Protein with Cardiac Biomarker Potential.

The ankyrin repeat domain 1 (ANKRD1) protein is a cardiac-specific stress-response protein that is part of the muscle ankyrin repeat protein family. ANKRD1 is functionally pleiotropic, playing pivotal roles in transcriptional regulation, sarcomere assembly and mechano-sensing in the heart. Importantly, cardiac ANKRD1 has been shown to be highly induced in various cardiomyopathies and in heart failure, although it is still unclear what impact this may have on the pathophysiology of heart failure. This review aims at highlighting the known properties, functions and regulation of ANKRD1, with focus on the underlying mechanisms that may be involved. The current views on the actions of ANKRD1 in cardiovascular disease and its utility as a candidate cardiac biomarker with diagnostic and/or prognostic potential are also discussed. More studies of ANKRD1 are warranted to obtain deeper functional insights into this molecule to allow assessment of its potential clinical applications as a diagnostic or prognostic marker and/or as a possible therapeutic target.

Protocol for Improving Care by FAster risk-STratification through use of high sensitivity point-of-care troponin in patients presenting with possible acute coronary syndrome in the EmeRgency department (ICare-FASTER): a stepped-wedge cluster randomised quality improvement initiative.

INTRODUCTION: Clinical assessment in emergency departments (EDs) for possible acute myocardial infarction (AMI) requires at least one cardiac troponin (cTn) blood test. The turn-around time from blood draw to posting results in the clinical portal for central laboratory analysers is ~1-2 hours. New generation, high-sensitivity, point-of-care cardiac troponin I (POC-cTnI) assays use whole blood on a bedside (or near bedside) analyser that provides a rapid (8 min) result. This may expedite clinical decision-making and reduce length of stay. Our purpose is to determine if utilisation of a POC-cTnI testing reduces ED length of stay. We also aim to establish an optimised implementation process for the amended clinical pathway. METHODS AND ANALYSIS: This quality improvement initiative has a pragmatic multihospital stepped-wedge cross-sectional cluster randomised design. Consecutive patients presenting to the ED with symptoms suggestive of possible AMI and having a cTn test will be included. Clusters (comprising one or two hospitals each) will change from their usual-care pathway to an amended pathway using POC-cTnI-the 'intervention'. The dates of change will be randomised. Changes occur at 1 month intervals, with a minimum 2 month 'run-in' period. The intervention pathway will use a POC-cTnI measurement as an alternate to the laboratory-based cTn measurement. Clinical decision-making steps and logic will otherwise remain unchanged. The POC-cTnI is the Siemens (Erlangen Germany) Atellica VTLi high-sensitivity cTnI assay. The primary outcome is ED length of stay. The safety outcome is cardiac death or AMI within 30 days for patients discharged directly from the ED. ETHICS AND DISSEMINATION: Ethics approval has been granted by the New Zealand Southern Health and Disability Ethics Committee, reference 21/STH/9. Results will be published in a peer-reviewed journal. Lay and academic presentations will be made. Maori-specific results will be disseminated to Maori stakeholders. TRIAL REGISTRATION NUMBER: ACTRN12619001189112.

Global Registry of Acute Coronary Events Score Underestimates Post-Acute Coronary Syndrome Mortality among Cancer Patients.

Background Patients with prior cancer are at increased risk of acute coronary syndrome (ACS) with poorer post-ACS outcomes. We aimed to ascertain if the Global Registry of Acute Coronary Events (GRACE) score accurately predicts mortality risk among patients with ACS and prior cancer. Methods We linked nationwide ACS and cancer registries from 2007 to 2018 in Singapore. A total of 24,529 eligible patients had in-hospital and 1-year all-cause mortality risk calculated using the GRACE score (2471 prior cancer; 22,058 no cancer). Results Patients with prior cancer had two-fold higher all-cause mortality compared to patients without cancer (in-hospital: 22.8% versus 10.3%, p < 0.001; 1-year: 49.0% vs. 18.7%, p < 0.001). Cardiovascular mortality did not differ between groups (in-hospital: 5.2% vs. 4.8%, p = 0.346; 1-year: 6.9% vs. 6.1%, p = 0.12). The area under the receiver operating characteristic curve of the GRACE score for prediction of all-cause mortality was less for prior cancer (in-hospital: 0.64 vs. 0.80, p < 0.001; 1-year: 0.66 vs. 0.83, p < 0.001). Among patients with prior cancer and a high-risk GRACE score > 140, in-hospital revascularization was not associated with lower cardiovascular mortality than without in-hospital revascularization (6.7% vs. 7.6%, p = 0.50). Conclusions The GRACE score performs poorly in risk stratification of patients with prior cancer and ACS.

Effective tools for RNA-derived therapeutics: siRNA interference or miRNA mimicry.

The approval of the first small interfering RNA (siRNA) drug Patisiran by FDA in 2018 marks a new era of RNA interference (RNAi) therapeutics. MicroRNAs (miRNA), an important post-transcriptional gene regulator, are also the subject of both basic research and clinical trials. Both siRNA and miRNA mimics are ~21 nucleotides RNA duplexes inducing mRNA silencing. Given the well performance of siRNA, researchers ask whether miRNA mimics are unnecessary or developed siRNA technology can pave the way for the emergence of miRNA mimic drugs. Through comprehensive comparison of siRNA and miRNA, we focus on (1) the common features and lessons learnt from the success of siRNAs; (2) the unique characteristics of miRNA that potentially offer additional therapeutic advantages and opportunities; (3) key areas of ongoing research that will contribute to clinical application of miRNA mimics. In conclusion, miRNA mimics have unique properties and advantages which cannot be fully matched by siRNA in clinical applications. MiRNAs are endogenous molecules and the gene silencing effects of miRNA mimics can be regulated or buffered to ameliorate or eliminate off-target effects. An in-depth understanding of the differences between siRNA and miRNA mimics will facilitate the development of miRNA mimic drugs.

Fibrinogen and hemoglobin predict near future cardiovascular events in asymptomatic individuals.

To identify circulating proteins predictive of acute cardiovascular disease events in the general population, we performed a proteomic screen in plasma from asymptomatic individuals. A "Discovery cohort" of 25 individuals who subsequently incurred a cardiovascular event within 3 years (median age = 70 years, 80% male) was matched to 25 controls remaining event-free for > 5 years (median age = 72 years, 80% male). Plasma proteins were assessed by data independent acquisition mass spectrometry (DIA-MS). Associations with cardiovascular events were tested using Cox regression, adjusted for the New Zealand Cardiovascular Risk Score. Concentrations of leading protein candidates were subsequently measured with ELISAs in a larger (n = 151) independent subset. In the Discovery cohort, 76 plasma proteins were robustly quantified by DIA-MS, with 8 independently associated with cardiovascular events. These included (HR = hazard ratio [95% confidence interval] above vs below median): fibrinogen alpha chain (HR = 1.84 [1.19-2.84]); alpha-2-HS-glycoprotein (also called fetuin A) (HR = 1.86 [1.19-2.93]); clusterin isoform 2 (HR = 1.59 [1.06-2.38]); fibrinogen beta chain (HR = 1.55 [1.04-2.30]); hemoglobin subunit beta (HR = 1.49 [1.04-2.15]); complement component C9 (HR = 1.62 [1.01-2.59]), fibronectin isoform 3 (HR = 0.60 [0.37-0.99]); and lipopolysaccharide-binding protein (HR = 1.58 [1.00-2.49]). The proteins for which DIA-MS and ELISA data were correlated, fibrinogen and hemoglobin, were analyzed in an Extended cohort, with broader inclusion criteria and longer time to events, in which these two proteins were not associated with incident cardiovascular events. We have identified eight candidate proteins that may independently predict cardiovascular events occurring within three years in asymptomatic, low-to-moderate risk individuals, although these appear not to predict events beyond three years.

Human Mesenchymal Stem Cell-derived Exosomes Reduce Ischemia/Reperfusion Injury by the Inhibitions of Apoptosis and Autophagy.

BACKGROUND: Human mesenchymal stem cell-derived exosomes (hMSC-Exo) have been shown to reduce ischemia/reperfusion injury (I/R) in multiple models. I/R-induced apoptosis or autophagy play important roles in cell death. However, little or no reports demonstrate any roles of hMSC-Exo in this regards. OBJECTIVE: To test the hypothesis that the inhibition of I/R-induced apoptosis and autophagy play a pivotal role in the cardioprotection of hMSC-Exo. METHODS: Myoblast H9c2 cells and isolated rat hearts underwent hypoxia/re-oxygenate (H/R) or ischemia/ reperfusion (I/R) respectively. H9c2 were treated with 1.0 µg/ml Exo, in comparison with 3-MA or rapamycin (Rapa), a known anti- or pro-autophagic agent respectively. Hearts were treated with 0.5, 1.0 and 2.0 µg/ml Exo for 20 min in the beginning of reperfusion. Cell viability, WST assay, LDH release, Annexin-V staining apoptosis assay and GFP-LC3 labeled autophagosomes formation, cardiac function and Western blot were measured. RESULTS: Exo significantly reduced H/R injury as indicated by increased cell viability and reduced LDH and apoptosis. 3-MA, while Rapa, showed increased or decreased protective effects. Rapa-induced injury was partially blocked by Exo. Exo decreased LC3-II/I ratio and increased p62, inhibited autophagosome formation, an indication of autophagy inhibition. In isolated heart, Exo increased cardiac functional recovery and reduced LDH release in I/R. Bcl-2 was significantly upregulated by Exo but not 3-MA. Exo downregulated Traf6 and upregulated mTORC1/p-4eBP1. CONCLUSION: Exo reduce I/R-induced apoptosis and autophagy. Up-regulation of Bcl-2 is the cross-talk between these two processes. The down-regulation of Traf6 and activation of mTORC1 are additional mechanisms in the inhibition of apoptosis and autophagy.

N-terminal pro-B-type natriuretic peptide-guided therapy in patients hospitalized for acute heart failure.

BACKGROUND: In patients with acute heart failure, high levels of N-terminal-pro-brain natriuretic peptide (NT-proBNP) at discharge are associated with worse outcomes. We hypothesized that NT-proBNP-guided therapy may improve prognosis. METHODS AND RESULTS: Two hundred and seventy-one consecutive patients, admitted for acute heart failure, were prospectively randomized to NT-proBNP-guided therapy or control group. The NT-proBNP-guided therapy group underwent medical treatment intensification when predischarge NT-proBNP was at least 3000 pg/ml. The primary endpoint was cardiovascular death or cardiovascular rehospitalization at day 182. The secondary endpoints were all-cause death, cardiovascular death, cardiovascular rehospitalization, heart failure rehospitalization, and cardiovascular death or heart failure rehospitalization at day 182. Treatment intensification in the NT-proBNP-guided therapy group regarded mainly diuretics. The NT-proBNP strategy was not associated with a significant reduction of the primary endpoint [43% intervention vs. 39% controls, hazard ratio 1.22 (0.84, 1.76), P = 0.305] and of any secondary endpoint. The change of NT-proBNP from predischarge to discharge was associated with the risk of cardiovascular death or cardiovascular rehospitalization through day 182, even after multivariable adjustment. CONCLUSION: NT-proBNP-guided therapy resulted mainly in an increase of diuretics in acute setting and compared with clinical evaluation alone did not improve prognosis. However, the reduction of NT-proBNP at discharge was an independent predictor of outcomes.

Growth differentiation factor 15 in heart failure with preserved vs. reduced ejection fraction.

AIM: Growth differentiation factor 15 (GDF15) is a cytokine highly expressed in states of inflammatory stress. We aimed to study the clinical correlates and prognostic significance of plasma GDF15 in heart failure with preserved ejection fraction (HFpEF) vs. reduced ejection fraction(HFrEF), compared with N-terminal pro-brain natriuretic peptide (NT-proBNP), an indicator of haemodynamic wall stress. METHODS: Plasma GDF15 and NT-proBNP were prospectively measured in 916 consecutive patients with HFrEF (EF <50%; n = 730) and HFpEF (EF ≥50%; n = 186), and measured again at 6 months in 488 patients. Patients were followed up for a composite outcome of death or first HF rehospitalization. RESULTS: Median GDF15baseline values were similarly elevated in HFpEF [2862 (1812 represent the 25th percentile and 4176 represent the 75th percentile) ng/L] and HFrEF [2517 (1555, 4030) ng/L] (P = 0.184), whereas NT-proBNP was significantly lower in HFpEF than HFrEF (1119 ng/L vs. 2335 ng/L, P < 0.001). Independent correlates of GDF15baseline were age, systolic blood pressure, New York Heart Association (NYHA) class, diabetes, atrial fibrillation, sodium, haemoglobin, creatinine, diuretic therapy, high sensitivity troponin T (hsTnT) and NT-proBNP (all P < 0.05). During a median follow-up of 23 months, there were 379 events (307 HFrEF, 72 HFpEF). GDF15 remained a significant independent predictor for composite outcome even after adjusting for important clinical predictors including hsTnT and NT-proBNP (adjusted hazard ratio 1.76 per 1 Ln U, 95% confidence interval 1.39-2.21; P < 0.001), regardless of HF group (Pinteraction = 0.275). GDF15baseline provided incremental prognostic value when added to clinical predictors, hsTnT and NT-proBNP (area under receiver operating characteristic curve increased from 0.720 to 0.740, P < 0.019), with a net reclassification improvement of 0.183 (P = 0.004). Patients with ≥20% GDF156months increase had higher risk for composite outcome (adjusted hazard ratio 1.68, 95% confidence interval 1.15-2.45; P = 0.007) compared with those with GDF156months within ± 20% of baseline. CONCLUSIONS: The similarly elevated levels and independent prognostic utility of GDF15 in HFrEF and HFpEF suggest that beyond haemodynamic stress (NT-proBNP), inflammatory injury (GDF15) may play an important role in both HF syndromes.

Differences in late cardiovascular mortality following acute myocardial infarction in three major Asian ethnic groups.

AIM: the purpose of this study was to investigate differences in long-term mortality following acute myocardial infarction (AMI) in patients from three major ethnicities of Asia. METHODS AND RESULTS: We studied 15,151 patients hospitalized for AMI with a median follow-up of 7.3 years (maximum 12 years) in six publicly-funded hospitals in Singapore from 2000-2005. Overall and cause-specific cardiovascular (CV) mortality until 2012 were compared among three major ethnic groups that represent large parts of Asia: Chinese, Malay and Indian. Relative survival of all three ethnic groups was compared with a contemporaneous background reference population using the relative survival ratio (RSR) method. The median global registry of acute coronary events score was highest among Chinese, followed by Malay and Indians: 144 (25th percentile 119, 75th percentile 173), 138 (115, 167), and 131 (109, 160), respectively, p<0.0001; similarly, in-hospital mortality was highest among Chinese (9.8%) followed by Malay (7.6%) and Indian (6.4%) patients. In contrast, 12-year overall and cause-specific CV mortality was highest among Malay (46.2 and 32.0%) followed by Chinese (43.0 and 27.0%) and Indian (35.9 and 25.2%) patients, p<0.0001. The five-year RSR was lowest among Malay (RSR 0.69) followed by Chinese (RSR 0.73) and Indian (RSR 0.79) patients, compared with a background reference population (RSR 1.00). CONCLUSIONS: We observed strong inter-Asian ethnic disparities in long-term mortality after AMI. Malay patients had the most discordant relationship between baseline risk and long-term mortality. Intensified interventions targeting Malay patients as a high-risk group are necessary to reduce disparities in long-term outcomes.