Multinational Federated Learning Approach to Train ECG and Echocardiogram Models for Hypertrophic Cardiomyopathy Detection.

BACKGROUND: Novel targeted treatments increase the need for prompt hypertrophic cardiomyopathy (HCM) detection. However, its low prevalence (0.5%) and resemblance to common diseases present challenges that may benefit from automated machine learning-based approaches. We aimed to develop machine learning models to detect HCM and to differentiate it from other cardiac conditions using ECGs and echocardiograms, with robust generalizability across multiple cohorts. METHODS: Single-institution HCM ECG models were trained and validated on external data. Multi-institution models for ECG and echocardiogram were trained on data from 3 academic medical centers in the United States and Japan using a federated learning approach, which enables training on distributed data without data sharing. Models were validated on held-out test sets for each institution and from a fourth academic medical center and were further evaluated for discrimination of HCM from aortic stenosis, hypertension, and cardiac amyloidosis. Last, automated detection was compared with manual interpretation by 3 cardiologists on a data set with a realistic HCM prevalence. RESULTS: We identified 74 376 ECGs for 56 129 patients and 8392 echocardiograms for 6825 patients at the 4 academic medical centers. Although ECG models trained on data from each institution displayed excellent discrimination of HCM on internal test data (C statistics, 0.88-0.93), the generalizability was limited, most notably for a model trained in Japan and tested in the United States (C statistic, 0.79-0.82). When trained in a federated manner, discrimination of HCM was excellent across all institutions (C statistics, 0.90-0.96 and 0.90-0.96 for ECG and echocardiogram model, respectively), including for phenotypic subgroups. The models further discriminated HCM from hypertension, aortic stenosis, and cardiac amyloidosis (C statistics, 0.84, 0.83, and 0.88, respectively, for ECG and 0.93, 0.94, 0.85, respectively, for echocardiogram). Analysis of electrocardiography-echocardiography paired data from 11 823 patients from an external institution indicated a higher sensitivity of automated HCM detection at a given positive predictive value compared with cardiologists (0.98 versus 0.81 at a positive predictive value of 0.01 for ECG and 0.78 versus 0.59 at a positive predictive value of 0.24 for echocardiogram). CONCLUSIONS: Federated learning improved the generalizability of models that use ECGs and echocardiograms to detect and differentiate HCM from other causes of hypertrophy compared with training within a single institution.

Inflammatory biomarkers and risk of cardiovascular events in patients undergoing coronary angiography.

BACKGROUND: Inflammation, measured by traditional biomarkers such as C-reactive protein, has been linked to cardiovascular (CV) events. Recent technological advancement has allowed for measuring larger numbers of inflammatory biomarkers. A contemporary evaluation with established and novel biomarkers of inflammation is needed. METHODS: 1,090 individuals who underwent coronary angiography were enrolled. Twenty-four inflammatory biomarkers were collected prior to angiography. Unsupervised machine learning cluster analyses determined unique patterns of inflammatory biomarkers. Cox proportional hazard regression assessed both association of inflammatory biomarker clusters and individual biomarker associations with major adverse cardiovascular events (MACE; non-fatal myocardial infarction or stroke, and CV death) during a median follow-up of 3.67 years. RESULTS: Four distinct clusters were recognized. Incremental increases in inflammatory biomarkers were observed from cluster 1 to cluster 4. During follow-up, 263 MACE were ascertained. Considering cluster 1 as a reference, study participants with inflammatory cluster 2 (Hazard ratio [HR] 1.55, 95% confidence interval [CI]: 1.01-2.37), cluster 3 (HR 1.89, CI: 1.25-2.85), and cluster 4 (HR 2.93, CI: 1.95-4.42) were at increased risk of MACE. Interleukin (IL)-1α IL-6, IL-8, IL-10, IL-12, Adhesion molecule-1 high-sensitivity C-reactive protein, ferritin, myeloperoxidase, macrophage inflammatory protein (MIP)-1a, MIP 3, and macrophage colony-stimulating factor-1 were independently associated with MACE. CONCLUSIONS: Among persons undergoing coronary angiography procedures, distinct clusters of inflammatory biomarker distributions with significant prognostic meaning may be identified. These results may identify unique targets for anti-inflammatory treatments aimed at CV disease.

Contemporary outpatient management of patients with worsening heart failure with reduced ejection fraction: Rationale and design of the CHART-HF study.

BACKGROUND: Patients with heart failure with reduced ejection fraction (HFrEF) and worsening HF events (WHFE) represent a distinct subset of patients with a substantial comorbidity burden, greater potential for intolerance to medical therapy, and high risk of subsequent death, hospitalization and excessive healthcare costs. Although multiple therapies have been shown to be efficacious and safe in this high-risk population, there are limited real-world data regarding factors that impact clinical decision-making when initiating or modifying therapy. Likewise, prior analyses of US clinical practice support major gaps in medical therapy for HFrEF and few medication changes during longitudinal follow-up, yet granular data on reasons why clinicians do not initiate or up-titrate guideline-directed medication are lacking. METHODS: We designed the CHART-HF study, an observational study of approximately 1,500 patients comparing patients with and without WHFE (WHFE defined as receipt of intravenous diuretics in the inpatient, outpatient, or emergency department setting) who had an index outpatient visit in the US between 2017 and 2019. Patient-level data on clinical characteristics, clinical outcomes, and therapy will be collected from 2 data sources: a single integrated health system, and a national panel of cardiologists. Furthermore, clinician-reported rationale for treatment decisions and the factors prioritized with selection and optimization of therapies in real-world practice will be obtained. To characterize elements of clinician decision-making not documented in the medical record, the panel of cardiologists will review records of patients seen under their care to explicitly note their primary reason for initiating, discontinuing, and titrating medications specific medications, as well as the reason for not making changes to each medication during the outpatient visit. CONCLUSIONS: Results from CHART-HF have the potential to detail real-world US practice patterns regarding care of patients with HFrEF with versus without a recent WHFE, to examine clinician-reported reasons for use and non-use of guideline-directed medical therapy, and to characterize the magnitude and nature of clinical inertia toward evidence-based medication changes for HFrEF.

Multiple Cardiac Biomarker Testing Among Patients With Acute Dyspnea From the ICON-RELOADED Study.

BACKGROUND: Among patients with acute dyspnea, concentrations of N-terminal pro-B-type natriuretic peptide (NT-proBNP), high-sensitivity cardiac troponin T, and insulin-like growth factor binding protein-7 predict cardiovascular outcomes and death. Understanding the optimal means to interpret these elevated biomarkers in patients presenting with acute dyspnea remains unknown. METHODS AND RESULTS: Concentrations of NT-proBNP, high-sensitivity cardiac troponin T, and insulin-like growth factor binding protein-7 were analyzed in 1448 patients presenting with acute dyspnea from the prospective, multicenter International Collaborative of NT-proBNP-Re-evaluation of Acute Diagnostic Cut-Offs in the Emergency Department (ICON-RELOADED) Study. Eight biogroups were derived based upon patterns in biomarker elevation at presentation and compared for differences in baseline characteristics. Of 441 patients with elevations in all 3 biomarkers, 218 (49.4%) were diagnosed with acute heart failure (HF). The frequency of acute HF diagnosis in this biogroup was higher than those with elevations in 2 biomarkers (18.8%, 44 of 234), 1 biomarker (3.8%, 10 of 260), or no elevated biomarkers (0.4%, 2 of 513). The absolute number of elevated biomarkers on admission was prognostic of the composite end point of mortality and HF rehospitalization. In adjusted models, patients with one, 2, and 3 elevated biomarkers had 3.74 (95% confidence interval [CI], 1.26-11.1, P = .017), 12.3 (95% CI, 4.60-32.9, P < .001), and 12.6 (95% CI, 4.54-35.0, P < .001) fold increased risk of 180-day mortality or HF rehospitalization. CONCLUSIONS: A multimarker panel of NT-proBNP, hsTnT, and IGBFP7 provides unique clinical, diagnostic, and prognostic information in patients presenting with acute dyspnea. Differences in the number of elevated biomarkers at presentation may allow for more efficient clinical risk stratification of short-term mortality and HF rehospitalization.

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.

Blood kidney injury molecule-1 predicts short and longer term kidney outcomes in patients undergoing diagnostic coronary and/or peripheral angiography-Results from the Catheter Sampled Blood Archive in Cardiovascular Diseases (CASABLANCA) study.

BACKGROUND: Kidney injury is common in patients with cardiovascular disease. OBJECTIVES: We determined whether blood measurement of kidney injury molecule-1 (KIM-1), would predict kidney outcomes in patients undergoing angiographic procedures for various indications. METHODS: One thousand two hundred eight patients undergoing coronary and/or peripheral angiography were prospectively enrolled; blood was collected for KIM-1 measurement. Peri-procedural acute kidney injury (AKI) was defined as AKI within 48 hours of contrast exposure. Non-procedural AKI was defined as AKI beyond 48 hours. Development of chronic kidney disease (CKD) was defined as progression to an estimated glomerular filtration rate (eGFR) <60 milliliters/minute/1.73 m2 by study conclusion. Univariate and multivariable Cox proportional hazards models were used to identify predictors of non-procedural AKI, while univariate and multivariable logistic regression analysis was used to evaluate peri-procedural AKI and predictors of progression to CKD. RESULTS: During mean follow up of 4 years, peri-procedural AKI occurred in 5.0%, non-procedural AKI in 27.3%, and 12.4% developed new reduction in eGFR <60 mL/min/1.73 m2. Higher KIM-1 concentrations were associated with prevalent comorbidities associated with risk in cardiovascular disease and worse left ventricular function. In adjusted analyses, elevated pre- and post-procedural KIM-1 concentrations predicted not only peri-procedural AKI (odds ratio [OR] 1.54, 95% confidence interval [CI] 1.09-2·18, P = .01 and OR 1.54, 95% CI 1.10-2.15, P = .01, respectively) and non-procedural AKI (hazard ratio [HR] 1·49, 95% CI 1·24-1·78, P < .001 and HR 1.46, 95% CI 1.23-1.74, P < .001, respectively), but also progression to CKD (OR 1.99, 95% CI 1.32-2.99, P = .001 and OR 2·02, 95% CI 1·35-3·03, P = .001, respectively). CONCLUSIONS: In a typical at-risk population undergoing coronary and/or peripheral angiography, blood concentrations of KIM-1 may predict incident peri-procedural and non-procedural AKI, as well as progression to CKD.

Incident Type 2 Myocardial Infarction in a Cohort of Patients Undergoing Coronary or Peripheral Arterial Angiography.

BACKGROUND: Despite growing recognition of type 2 myocardial infarction (T2MI; related to supply/demand mismatch), little is known about its risk factors or its association with outcome. METHODS: A single-center cohort of patients undergoing coronary or peripheral angiography with or without intervention was prospectively enrolled and followed for incident type 1 and T2MI, and major adverse cardiovascular events (MACE, a composite of all-cause death, nonfatal myocardial infarction [MI], heart failure, stroke, transient ischemic attack, peripheral arterial complication, and cardiac arrhythmia), as well. T2MI was adjudicated using criteria from the Third Universal Definition of MI. Baseline characteristics, blood samples, and angiography information were obtained. Major end points subsequent to first MI were assessed using landmark analyses to compare the rates of first events only where everyone with a prior history of any MACE before MI were censored and adjusted for follow-up times. Cox proportional hazard models were used for time-to-event analyses with age and sex forced into all models and additional covariates evaluated by using the stepwise option for the selection. RESULTS: One thousand two hundred fifty-one patients were enrolled and followed for a median of 3.4 years. Of these patients, 152 (12.2%) had T2MI during follow-up; T2MI was frequently recurrent. Multivariable predictors of T2MI were older age, lower systolic blood pressure, history of coronary artery disease, heart failure, chronic obstructive pulmonary disease, diabetes mellitus, nitrate use, and elevated concentrations of glucose, N-terminal pro-B type natriuretic peptide, and cystatin C. Patients with T2MI had higher rates of subsequent adverse events than those without T2MI (per 100 person-years: MACE, 53.7 versus 21.1, P<0.001; all-cause death, 23.3 versus 3.3, P<0.001; cardiovascular death, 17.5 versus 2.6, P<0.001; heart failure events, 22.4 versus 7.4, P<0.001); these rates are similar to those seen in patients with type 1 MI. Incident diagnosis of T2MI strongly predicted risk for subsequent MACE (adjusted hazard ratio, 1.90; 95% confidence interval, 1.46-2.48; P<0.001), all-cause death (adjusted hazard ratio, 2.96; 95% confidence interval, 2.01-4.36; P<0.001), and cardiovascular death (adjusted hazard ratio, 2.16; 95% confidence interval, 1.36-3.43; P=0.001). CONCLUSIONS: T2MI is common and associated with poor prognosis. Studies evaluating treatment strategies for management of T2MI are needed. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00842868.

Endothelin-1 Measurement in Patients Undergoing Diagnostic Coronary Angiography-Results from the Catheter Sampled Blood Archive in Cardiovascular Diseases (CASABLANCA) Study.

BACKGROUND: Endothelin-1 (ET-1) is a vasoconstrictor produced by vascular endothelial cells and may play a role in risk for development of coronary artery disease (CAD) and heart failure (HF). In a cohort of 1084 patients referred for coronary angiography, we investigated cross-sectional associations between ET-1 concentrations and prevalent CAD, as well as value of ET-1 for prognostication of future cardiovascular events. METHODS: Associations between ET-1 and presence/severity of CAD were assessed. Patients were followed for a median of 4 years for outcomes including incident HF, myocardial infarction (MI), cardiovascular mortality, and all-cause mortality. RESULTS: The median concentration of ET-1 was 2.57 ng/L. Patients with ET-1 concentrations above the median were more likely to have higher risk clinical features. Among those without prevalent MI at presentation, ET-1 concentrations were not associated with presence or severity of CAD. In adjusted Cox proportional hazards analyses, log-transformed ET-1 concentrations predicted incident HF [hazard ratio (HR) = 1.51 per increase in log-SD; 95% CI, 1.06-2.15; P = 0.02] and all-cause mortality (HR = 1.61 per increase in log-SD; 95% CI, 1.03-2.53; P = 0.04). Concentrations of ET-1 above the median were associated with shorter time to incident HF, MI, cardiovascular mortality, all-cause mortality, and the composite of incident HF/MI/cardiovascular mortality (all log-rank P < 0.001). CONCLUSIONS: Despite epidemiologic links to CAD, we found no cross-sectional association between biologically active ET-1 and prevalent coronary atherosclerosis in an at-risk population referred for coronary angiography. Increased ET-1 concentrations independently predict incident HF and death and are associated with more near-term cardiovascular events.

Type 2 Myocardial Infarction　- An Evolving Entity.

Type 2 myocardial infarction (T2MI) refers to myocardial necrosis caused by an imbalance in myocardial oxygen supply and demand and in the absence of acute coronary thrombosis. Despite growing recognition of this entity, there remains little understanding of the pathophysiology and uncertainty over the diagnostic criteria for this subtype of MI. Alarmingly, recent studies suggest that a diagnosis of T2MI pertains a prognosis similar to, if not worse than, type 1 MI. With increasing clinical use of high-sensitivity cardiac troponin assays, the frequency of recognition of T2MI is expected to increase. Yet, there remains a scarcity of prospective studies examining this cohort of patients, let alone randomized clinical trials identifying optimum treatment strategies. Further evaluation of the prevalence, pathophysiology and management of this patient cohort is warranted by the scientific community.

Worsening Renal Function during Management for Chronic Heart Failure with Reduced Ejection Fraction: Results From the Pro-BNP Outpatient Tailored Chronic Heart Failure Therapy (PROTECT) Study.

OBJECTIVES: To assess prognostic meaning of worsening renal failure (WRF) occurring during management of chronic heart failure (HF) with reduced ejection fraction. BACKGROUND: When WRF develops during titration of HF medical therapy, it commonly leads to less aggressive care. METHODS: A total of 151 patients enrolled in a prospective, randomized study of standard of care (SOC) HF therapy versus SOC plus a goal N-terminal pro-B type natriuretic peptide (NT-proBNP) < 1000 pg/mL were examined. Cardiovascular (CV) event (defined as worsening HF, hospitalization for HF, significant ventricular arrhythmia, acute coronary or cerebral ischemia, or CV death) at 1 year relative to WRF (defined as any reduction in estimated glomerular filtration rate) 90 days postenrollment were tabulated. RESULTS: Those developing WRF by 3 months had an average 14% reduction in estimated glomerular filtration rate. There was no difference in incidence of WRF between study arms (43% in SOC, 57% in NT-proBNP, P = .29). During the first 3 months of therapy titration, incident WRF was associated with numerically fewer CV events at 1 year compared with those without WRF (mean 0.81 vs 1.16 events, P = .21). WRF was associated trend toward fewer CV events in the SOC arm (hazard ratio 0.45, 95% confidence interval 0.16-1.24, P = .12); the NT-proBNP-guided arm had numerically lower CV event rates regardless of WRF. Subjects with NT-proBNP <1000 pg/mL and WRF received higher doses of guideline directed medical therapies, lower doses of loop diuretics, and had significantly lower CV event rates (P < .001). CONCLUSIONS: Modest degrees of WRF are common during aggressive HF with reduced ejection fraction management, but we found no significant association with CV outcomes. HF care guided by NT-proBNP was not associated with more WRF compared with SOC, and led to benefit regardless of final renal function.

Prognostic Value of Insulin-Like Growth Factor-Binding Protein 7 in Patients with Heart Failure and Preserved Ejection Fraction.

BACKGROUND: The prognostic merit of insulin-like growth factor-binding protein 7 (IGFBP7) is unknown in heart failure and preserved ejection fraction (HFpEF). METHODS AND RESULTS: Baseline IGFBP7 (BL-IGFBP7; n = 302) and 6-month change (Δ; n = 293) were evaluated in the Irbesartan in Heart Failure and Preserved Ejection Fraction (I-PRESERVE) trial. Primary outcome was all-cause mortality or cardiovascular hospitalization with median follow-up of 3.6 years; secondary outcomes included HF events. Median BL-IGFBP7 concentration was 218 ng/mL. BL-IGFBP7 was significantly correlated with age (R2 = 0.13; P < .0001), amino-terminal pro-B-type NP (R2 = 0.22; P < .0001), and estimated glomerular filtration rate (eGFR; R2 = 0.14; P < .0001), but not with signs/symptoms of HFpEF. BL-IGFBP7 was significantly associated with the primary outcome (hazard ratio [HR] = 1.007 per ng/mL; P < .001), all-cause mortality (HR = 1.008 per ng/mL; P < .001), and HF events (HR = 1.007 per ng/mL; P < .001). IGFBP7 remained significant for each outcome after adjustment for ln amino-terminal pro-B-type NP and eGFR but not all variables in the I-PRESERVE prediction model. After 6 months, IGFBP7 did not change significantly in either treatment group. ΔIGFBP7 was significantly associated with decrease in eGFR in patients randomized to irbesartan (R2 = 0.09; P = .002). ΔIGFBP7 was not independently associated with outcome. CONCLUSIONS: Higher concentrations of IGFBP7 were associated with increased risk of cardiovascular events, but after multivariable adjustment this association was no longer present. Further studies of IGFBP7 are needed to elucidate its mechanism. CLINICAL TRIAL REGISTRATION: www.clinicaltrials.gov, NCT00095238.

Biomarkers to Predict Reverse Remodeling and Myocardial Recovery in Heart Failure.

Left ventricular remodeling appears to be a critical link between cardiac injury and the development and progression of heart failure with reduced ejection fraction (HFrEF). Several drug and device therapies that modify and reverse the remodeling process in patients with HFrEF are closely associated with improvement in clinical outcomes. Reverse remodeling, including partial or complete recovery of systolic function and structure, is possible but its determinants are incompletely understood. Methods to predict reverse remodeling in response to therapy are not well defined. Though non-invasive imaging techniques remain the most widely used methods of assessing reverse remodeling, serum biomarkers are now being investigated as more specific, mechanistically driven, and clinically useful predictors of reverse remodeling. Biomarkers that reflect myocyte stretch and stress, myocyte injury and necrosis, inflammation and fibrosis, and extracellular matrix turnover may be particularly valuable for predicting pathophysiologic changes and prognosis in individual patients. Their use may ultimately allow improved application of precision medicine in chronic HF.

Galectin-3 and mineralocorticoid receptor antagonist use in patients with chronic heart failure due to left ventricular systolic dysfunction.

BACKGROUND: Galectin-3 is a prognostic heart failure biomarker associated with aldosterone-induced myocardial fibrosis; mineralocorticoid receptor antagonists (MRAs) may reduce such fibrosis. We sought to examine outcomes of patients with heart failure with reduced ejection fraction (HFrEF) as a function of galectin-3 and MRA therapy. METHODS: A total of 151 patients with chronic HFrEF were categorized by baseline galectin-3 and subsequent MRA therapy trends with regard to cardiovascular (CV) events, left ventricular remodeling, safety, and quality of life, over a mean of 10 months. RESULTS: Although galectin-3 >20 ng/mL was associated with doubling in adjusted risk for CV events, regardless of MRA treatment, there was no difference in CV event rates with regard to MRA use patterns, independent of galectin-3 concentrations. Specifically, in patients with elevated galectin-3 treated with intensified MRA therapy, a significant difference was not detected in CV event rates (P = .79) or the cumulative number of such events (P = .76). Adjusted analysis revealed no difference in time to first CV event if MRA was added/intensified in those with elevated galectin-3 (hazard ratio 0.99, 95% CI 0.97-1.02, P = .74); similarly, cumulative MRA dose was not a specific predictor of benefit. In those with elevated galectin-3, MRA therapy did not affect left ventricular remodeling indices or quality of life at follow-up; these patients had the highest rates of treatment-related adverse events with intensified MRA use. Regardless of MRA use, elevated galectin-3 was associated with more significant renal dysfunction. CONCLUSIONS: Among patients with chronic HFrEF and elevated galectin-3 concentrations, we found no specific benefit from addition or intensification of MRA therapy.

Characterization and prediction of adverse events from intensive chronic heart failure management and effect on quality of life: results from the pro-B-type natriuretic peptide outpatient-tailored chronic heart failure therapy (PROTECT) study.

BACKGROUND: Serious adverse events (SAEs) from heart failure (HF) therapy are frequent; however, techniques to identify at-risk patients are inadequate. Furthermore, the relationship between SAEs, quality of life (QOL), and cardiac structure are unknown. METHODS AND RESULTS: 151 symptomatic patients with systolic HF were followed for a mean of 10 months. In this post hoc analysis, treatment-related SAEs included acute renal failure, dizziness, hypo/hyperkalemia, hypotension, and syncope. At 1 year, 21 treatment-related SAEs occurred. No difference in SAEs existed between the N-terminal pro-B-type natriuretic peptide (NT-proBNP)-guided arm and the standard of care arm (P = .20). At baseline, patients who suffered SAEs were less likely to be receiving beta-blockers (85.7% vs 97.7%; P = .009) and had worse functional class and lower chloride levels. Patients who experienced SAEs had less improvement in their Minnesota Living With Heart Failure Questionnaire scores and had a trend toward reduced echocardiographic reverse remodeling over the follow-up period. Univariable and multivariable analyses were conducted to develop a risk score for SAE prediction; patients in the highest risk quartile had the shortest time to first cardiovascular event (P = 0.01). CONCLUSIONS: NT-proBNP-guided HF care is safe. Experiencing treatment-related SAEs is associated with worse QOL and potentially reduced reverse remodeling. A risk score to prospectively predict SAEs in aggressive HF management was developed.

ST2 pathogenetic profile in ambulatory heart failure patients.

BACKGROUND: Soluble ST2 is involved in multiple pathogenic pathways, including cardiac strain, inflammation, and myocardial necrosis with remodeling. The relative weight of ST2 and the point at which its prognostic value in heart failure (HF) is affected by different degrees of myocardial strain, inflammation, necrosis, and remodeling is unknown. METHODS AND RESULTS: We examined whether soluble ST2 levels improves HF risk stratification relative to other biomarkers representative of multiple pathogenic pathways-N-terminal pro-B-type natriuretic peptide (NT-proBNP; strain), high-sensitivity C-reactive protein (hsCRP; inflammation), and galectin-3 and high-sensitivity troponin T (hsTnT; necrosis and remodeling)-in 1,015 patients with mean left ventricular ejection fraction (LVEF) 33.5%. Mean follow-up was 4.2 ± 2.1 years. The correlation with soluble ST2 was highest with NT-proBNP (r = 0.32; P < .001) and lowest with galectin-3 (r = 0.15; P < .001). ST2 levels increased with increasing concentrations of the other biomarkers (P < .001 in all cases). During follow-up, 467 patients died. Soluble ST2 remained an independent prognosticator of risk at every tertile of each biomarker. This was observed even after adjusting for clinical parameters. CONCLUSIONS: Soluble ST2 may be regarded as a 3-in-1 prognosis biomarker in HF. ST2 provides valuable long-term risk stratification information in HF beyond that reported by other biomarkers of stretch, inflammation, necrosis, and remodeling.

Comparison between admission natriuretic peptides, NGAL and sST2 testing for the prediction of worsening renal function in patients with acutely decompensated heart failure.

BACKGROUND: In order to predict the occurrence of worsening renal function (WRF) and of WRF plus in-hospital death, 101 emergency department (ED) patients with acute decompensated heart failure (ADHF) were evaluated with testing for amino-terminal pro-B-type natriuretic peptide (NT-proBNP), BNP, sST2, and neutrophil gelatinase associated lipocalin (NGAL). METHODS: In a prospective international study, biomarkers were collected at the time of admission; the occurrence of subsequent in hospital WRF was evaluated. RESULTS: In total 26% of patients developed WRF. Compared to patients without WRF, those with WRF had a longer in-hospital length of stay (LOS) (mean LOS 13.1±13.4 days vs. 4.8±3.7 days, p<0.001) and higher in-hospital mortality [6/26 (23%) vs. 2/75 (2.6%), p<0.001]. Among the biomarkers assessed, baseline NT-proBNP (4846 vs. 3024 pg/mL; p=0.04), BNP (609 vs. 435 pg/mL; p=0.05) and NGAL (234 vs. 174 pg/mL; p=0.05) were each higher in those who developed WRF. In logistic regression, the combination of elevated natriuretic peptide and NGAL were additively predictive for WRF (ORNT-proBNP+NGAL=2.79; ORBNP+NGAL=3.11; both p<0.04). Rates of WRF were considerably higher in patients with elevation of both classes of biomarker. Comparable results were observed in a separate cohort of 162 patients with ADHF from a different center. CONCLUSIONS: In ED patients with ADHF, the combination of NT-proBNP or BNP plus NGAL at presentation may be useful to predict impending WRF (Clinicaltrials.gov NCT#0150153).

Effect of B-type natriuretic peptide-guided treatment of chronic heart failure on total mortality and hospitalization: an individual patient meta-analysis.

AIMS: Natriuretic peptide-guided (NP-guided) treatment of heart failure has been tested against standard clinically guided care in multiple studies, but findings have been limited by study size. We sought to perform an individual patient data meta-analysis to evaluate the effect of NP-guided treatment of heart failure on all-cause mortality. METHODS AND RESULTS: Eligible randomized clinical trials were identified from searches of Medline and EMBASE databases and the Cochrane Clinical Trials Register. The primary pre-specified outcome, all-cause mortality was tested using a Cox proportional hazards regression model that included study of origin, age (<75 or ≥75 years), and left ventricular ejection fraction (LVEF, ≤45 or >45%) as covariates. Secondary endpoints included heart failure or cardiovascular hospitalization. Of 11 eligible studies, 9 provided individual patient data and 2 aggregate data. For the primary endpoint individual data from 2000 patients were included, 994 randomized to clinically guided care and 1006 to NP-guided care. All-cause mortality was significantly reduced by NP-guided treatment [hazard ratio = 0.62 (0.45-0.86); P = 0.004] with no heterogeneity between studies or interaction with LVEF. The survival benefit from NP-guided therapy was seen in younger (<75 years) patients [0.62 (0.45-0.85); P = 0.004] but not older (≥75 years) patients [0.98 (0.75-1.27); P = 0.96]. Hospitalization due to heart failure [0.80 (0.67-0.94); P = 0.009] or cardiovascular disease [0.82 (0.67-0.99); P = 0.048] was significantly lower in NP-guided patients with no heterogeneity between studies and no interaction with age or LVEF. CONCLUSION: Natriuretic peptide-guided treatment of heart failure reduces all-cause mortality in patients aged <75 years and overall reduces heart failure and cardiovascular hospitalization.

Biomarkers and diagnostics in heart failure.

Heart failure (HF) biomarkers have dramatically impacted the way HF patients are evaluated and managed. B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) are the gold standard biomarkers in determining the diagnosis and prognosis of HF, and studies on natriuretic peptide-guided HF management look promising. An array of additional biomarkers has emerged, each reflecting different pathophysiological processes in the development and progression of HF: myocardial insult, inflammation and remodeling. Novel biomarkers, such as mid-regional pro atrial natriuretic peptide (MR-proANP), mid-regional pro adrenomedullin (MR-proADM), highly sensitive troponins, soluble ST2 (sST2), growth differentiation factor (GDF)-15 and Galectin-3, show potential in determining prognosis beyond the established natriuretic peptides, but their role in the clinical care of the patient is still partially defined and more studies are needed. This article is part of a Special Issue entitled: Heart failure pathogenesis and emerging diagnostic and therapeutic interventions.

Reference interval evaluation of high-sensitivity troponin T and N-terminal B-type natriuretic peptide in Vietnam and the US: The North South East West Trial.

BACKGROUND: Reference intervals of high-sensitivity troponin T (hs-cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) have been determined from Western populations. No data are available regarding expected values in Asian populations. METHODS: A total of 1157 age- and sex-matched healthy individuals (mean age, 41.2 years; 48.0% male) were prospectively enrolled from the US (n = 565) and Vietnam (n = 592). Blood samples were analyzed for hs-cTnT and NT-proBNP. Median values were determined for each country and compared in unadjusted analyses and in analyses adjusted for age, sex, body mass index, study site, race, and vital signs. RESULTS: Median hs-cTnT concentrations were slightly higher for individuals from the US than for those from Vietnam, but both were below the limit of detection (3.7 vs 3.0 ng/L, respectively; P = 0.03). More US participants had an hs-cTnT concentration above the limit of detection (57.2% vs 47.3%; P = 0.001), but the 99th percentile concentration was slightly higher for Asians (US 15.1 vs Vietnam 19.0 ng/L). Concentrations for >98% of both populations were below the standard hs-cTnT 99th percentile of 14.0 ng/L (P = 0.54). Median NT-proBNP concentrations were slightly higher for US participants compared with Vietnamese participants (28 vs 16 ng/L, respectively; P < 0.001). Following adjustment, differences in concentrations of NT-proBNP between healthy US and Vietnamese populations remained significant, whereas for hs-cTnT the differences were no longer significant. Inclusion of hs-cTnT values down to the limit of blank did not change the result. CONCLUSIONS: The differences in hs-cTnT and NT-proBNP between healthy individuals from the US and Vietnam are small. Previously derived reference intervals for both analytes may be applied in Asian populations.