Incident heart failure in chronic kidney disease: proteomics informs biology and risk stratification.

BACKGROUND AND AIMS: Incident heart failure (HF) among individuals with chronic kidney disease (CKD) incurs hospitalizations that burden patients and health care systems. There are few preventative therapies, and the Pooled Cohort equations to Prevent Heart Failure (PCP-HF) perform poorly in the setting of CKD. New drug targets and better risk stratification are urgently needed. METHODS: In this analysis of incident HF, SomaScan V4.0 (4638 proteins) was analysed in 2906 participants of the Chronic Renal Insufficiency Cohort (CRIC) with validation in the Atherosclerosis Risk in Communities (ARIC) study. The primary outcome was 14-year incident HF (390 events); secondary outcomes included 4-year HF (183 events), HF with reduced ejection fraction (137 events), and HF with preserved ejection fraction (165 events). Mendelian randomization and Gene Ontology were applied to examine causality and pathways. The performance of novel multi-protein risk models was compared to the PCP-HF risk score. RESULTS: Over 200 proteins were associated with incident HF after adjustment for estimated glomerular filtration rate at P < 1 × 10-5. After adjustment for covariates including N-terminal pro-B-type natriuretic peptide, 17 proteins remained associated at P < 1 × 10-5. Mendelian randomization associations were found for six proteins, of which four are druggable targets: FCG2B, IGFBP3, CAH6, and ASGR1. For the primary outcome, the C-statistic (95% confidence interval [CI]) for the 48-protein model in CRIC was 0.790 (0.735, 0.844) vs. 0.703 (0.644, 0.762) for the PCP-HF model (P = .001). C-statistic (95% CI) for the protein model in ARIC was 0.747 (0.707, 0.787). CONCLUSIONS: Large-scale proteomics reveal novel circulating protein biomarkers and potential mediators of HF in CKD. Proteomic risk models improve upon the PCP-HF risk score in this population.

Low concentrations of medium-sized HDL particles predict incident CVD in chronic kidney disease patients.

Patients with chronic kidney disease (CKD) are at high risk for CVD. However, traditional CVD risk factors cannot completely explain the increased risk. Altered HDL proteome is linked with incident CVD in CKD patients, but it is unclear whether other HDL metrics are associated with incident CVD in this population. In the current study, we analyzed samples from two independent prospective case-control cohorts of CKD patients, the Clinical Phenotyping and Resource Biobank Core (CPROBE) and the Chronic Renal Insufficiency Cohort (CRIC). We measured HDL particle sizes and concentrations (HDL-P) by calibrated ion mobility analysis and HDL cholesterol efflux capacity (CEC) by cAMP-stimulated J774 macrophages in 92 subjects from the CPROBE cohort (46 CVD and 46 controls) and in 91 subjects from the CRIC cohort (34 CVD and 57 controls). We tested associations of HDL metrics with incident CVD using logistic regression analysis. No significant associations were found for HDL-C or HDL-CEC in either cohort. Total HDL-P was only negatively associated with incident CVD in the CRIC cohort in unadjusted analysis. Among the six sized HDL subspecies, only medium-sized HDL-P was significantly and negatively associated with incident CVD in both cohorts after adjusting for clinical confounders and lipid risk factors with odds ratios (per 1-SD) of 0.45 (0.22-0.93, P = 0.032) and 0.42 (0.20-0.87, P = 0.019) for CPROBE and CRIC cohorts, respectively. Our observations indicate that medium-sized HDL-P-but not other-sized HDL-P or total HDL-P, HDL-C, or HDL-CEC-may be a prognostic cardiovascular risk marker in CKD.

Excess risk of cardiovascular events in patients in the United States vs. Japan with chronic kidney disease is mediated mainly by left ventricular structure and function.

While patients receiving dialysis therapy in the United States are more likely to develop cardiovascular disease (CVD) than those in Japan, direct comparisons of patients with predialysis chronic kidney disease (CKD) are rare. To study this, we compared various outcomes in patients with predialysis CKD using data from the Chronic Renal Insufficiency Cohort (CRIC) and CKD Japan Cohort (CKD-JAC) studies and determined mediators of any differences. Candidate mediators included left ventricular (LV) indices assessed by echocardiography. Among 3125 CRIC and 1097 CKD-JAC participants, the mean LV mass index (LVMI) and ejection fraction (EF) were 55.7 and 46.6 g/m2 and 54% and 65%, respectively (both significant). The difference in body mass index (32 and 24 kg/m2, respectively) largely accounted for the differences in LVMI and C-reactive protein levels across cohorts. Low EF and high LVMI were significantly associated with subsequent CVD in both cohorts. During a median follow-up of five years, CRIC participants were at higher risk for CVD (adjusted hazard ratio [95% confidence interval]: 3.66 [2.74-4.89]) and death (4.69 [3.05-7.19]). A three-fold higher C-reactive protein concentration and higher phosphate levels in the United States cohort were moderately strong mediators of the differences in CVD. However, echocardiographic parameters were stronger mediators than these laboratory measures. LVMI, EF and their combination mediated the observed difference in CVD (27%, 50%, and 57%, respectively) and congestive heart failure (33%, 62%, and 70%, respectively). Thus, higher LV mass and lower EF, even in the normal range, were found to be predictive of CVD in CKD.

Cardiac Structure and Function and Subsequent Kidney Disease Progression in Adults With CKD: The Chronic Renal Insufficiency Cohort (CRIC) Study.

RATIONALE & OBJECTIVE: Heart-kidney crosstalk is recognized as the cardiorenal syndrome. We examined the association of cardiac function and structure with the risk of kidney failure with replacement therapy (KFRT) in a chronic kidney disease (CKD) population. STUDY DESIGN: Prospective observational cohort study. SETTING & PARTICIPANTS: 3,027 participants from the Chronic Renal Insufficiency Cohort Study. EXPOSURE: Five preselected variables that assess different aspects of cardiac structure and function: left ventricular mass index (LVMI), LV volume, left atrial (LA) area, peak tricuspid regurgitation (TR) velocity, and left ventricular ejection fraction (EF) as assessed by echocardiography. OUTCOME: Incident KFRT (primary outcome), and annual estimated glomerular filtration rate (eGFR) slope (secondary outcome). ANALYTICAL APPROACH: Multivariable Cox models and mixed-effects models. RESULTS: The mean age of the participants was 59±11 SD years, 54% were men, and mean eGFR was 43±17mL/min/1.73m2. Between 2003 and 2018 (median follow-up, 9.9 years), 883 participants developed KFRT. Higher LVMI, LV volume, LA area, peak TR velocity, and lower EF were each statistically significantly associated with an increased risk of KFRT, with corresponding HRs for the highest versus lowest quartiles (lowest vs highest for EF) of 1.70 (95% CI, 1.27-2.26), 1.50 (95% CI, 1.19-1.90), 1.43 (95% CI, 1.11-1.84), 1.45 (95% CI, 1.06-1.96), and 1.26 (95% CI, 1.03-1.56), respectively. For the secondary outcome, participants in the highest versus lowest quartiles (lowest vs highest for EF) had a statistically significantly faster eGFR decline, except for LA area (ΔeGFR slope per year, -0.57 [95% CI, -0.68 to-0.46] mL/min/1.73m2 for LVMI, -0.25 [95% CI, -0.35 to-0.15] mL/min/1.73m2 for LV volume, -0.01 [95% CI, -0.12 to-0.01] mL/min/1.73m2 for LA area, -0.42 [95% CI, -0.56 to-0.28] mL/min/1.73m2 for peak TR velocity, and -0.11 [95% CI, -0.20 to-0.01] mL/min/1.73m2 for EF, respectively). LIMITATIONS: The possibility of residual confounding. CONCLUSIONS: Multiple aspects of cardiac structure and function were statistically significantly associated with the risk of KFRT. These findings suggest that cardiac abnormalities and incidence of KFRT are potentially on the same causal pathway related to the interaction between hypertension, heart failure, and coronary artery diseases. PLAIN-LANGUAGE SUMMARY: Heart disease and kidney disease are known to interact with each other. In this study, we examined whether cardiac abnormalities, as assessed by echocardiography, were linked to the subsequent progression of kidney disease among people living with chronic kidney disease (CKD). We found that people with abnormalities in heart structure and function had a greater risk of progression to advanced CKD that required kidney replacement therapy and had a faster rate of decline in kidney function. Our study indicates the potential role of abnormal heart structure and function in the progression of kidney disease among people living with CKD.

IL-18 mediates sickle cell cardiomyopathy and ventricular arrhythmias.

Previous reports indicate that IL18 is a novel candidate gene for diastolic dysfunction in sickle cell disease (SCD)-related cardiomyopathy. We hypothesize that interleukin-18 (IL-18) mediates the development of cardiomyopathy and ventricular tachycardia (VT) in SCD. Compared with control mice, a humanized mouse model of SCD exhibited increased cardiac fibrosis, prolonged duration of action potential, higher VT inducibility in vivo, higher cardiac NF-κB phosphorylation, and higher circulating IL-18 levels, as well as reduced voltage-gated potassium channel expression, which translates to reduced transient outward potassium current (Ito) in isolated cardiomyocytes. Administering IL-18 to isolated mouse hearts resulted in VT originating from the right ventricle and further reduced Ito in SCD mouse cardiomyocytes. Sustained IL-18 inhibition via IL-18-binding protein resulted in decreased cardiac fibrosis and NF-κB phosphorylation, improved diastolic function, normalized electrical remodeling, and attenuated IL-18-mediated VT in SCD mice. Patients with SCD and either myocardial fibrosis or increased QTc displayed greater IL18 gene expression in peripheral blood mononuclear cells (PBMCs), and QTc was strongly correlated with plasma IL-18 levels. PBMC-derived IL18 gene expression was increased in patients who did not survive compared with those who did. IL-18 is a mediator of sickle cell cardiomyopathy and VT in mice and a novel therapeutic target in patients at risk for sudden death.

Defining the impact of continuous positive airway pressure therapy on diastolic function in adults with moderate-to-severe obstructive sleep apnea.

Although studies have shown that continuous positive airway pressure (CPAP) therapy to treat obstructive sleep apnea improves left ventricular diastolic function, modifiers of improvement are unknown. We explored race and pre-treatment 24-h non-dipping blood pressure status as modifiers of improved diastolic function. Participants (N = 220) with obstructive sleep apnea (apnea-hypopnea index ≥15 events/h) and hypertension were recruited to a cohort study that examined effects of 3-month CPAP therapy on 24-h blood pressure. Those who completed echocardiogram at baseline and follow-up were included in this analysis. Diastolic function parameters (E, A, e', E/A, E/e') were assessed. Race was categorised to African American versus others. Participants were categorised as nocturnal dippers (night-time blood pressure decrease by ≥10%) versus non-dippers. We compared changes in parameters of diastolic function by race and nocturnal dipping status. A total of 92 participants were included. They were men (86%), African American (67.4%), and current smoker (29.5%). Mean apnea-hypopnea index was 32.9 events/h. Mean CPAP usage was 3.15 h/day. After 3 months of CPAP treatment, there were significant improvements in measures of diastolic function: a median (interquartile range [IQR]) increase in E velocity by 4.00 (-5.75 to 13.75) cm/s, an increase in e' by 2.00 (0-4.00) cm/s, and a decrease in the E/e' ratio by 1.74 (-4.27 to 0.00) at follow-up (p < 0.05). These changes did not differ by race or nocturnal dipping status. Improvements in diastolic function after CPAP therapy did not differ by race or nocturnal dipping status. Further studies are needed to understand predictors of CPAP effects on diastolic function.

Self-reported Physical Activity and Cardiovascular Events in Adults With CKD: Findings From the CRIC (Chronic Renal Insufficiency Cohort) Study.

RATIONALE & OBJECTIVE: In the general population, there is an association between higher levels of physical activity and lower risk for cardiovascular events and mortality, but this relationship has not been well evaluated in chronic kidney disease (CKD). We investigated the association between self-reported physical activity and outcomes in a CKD cohort. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 3,926 participants in the Chronic Renal Insufficiency Cohort (CRIC) Study. EXPOSURE: Time-updated self-reported physical activity assessed by (1) quartile of moderate-to-vigorous physical activity (MVPA) and (2) meeting guideline-recommended level of physical activity (categorized as active, meeting guidelines; active, not meeting guidelines; or inactive). OUTCOME: Atherosclerotic events (myocardial infarction, stroke, or peripheral artery disease), incident heart failure, and all-cause and cardiovascular death. ANALYTICAL APPROACH: Cox proportional hazards regression. RESULTS: At baseline, compared with the lowest MVPA quartile, those in the highest quartile were more likely to be younger, male, not have prevalent cardiovascular disease, and have higher estimated glomerular filtration rate. Overall, 51% met the physical activity guidelines; of those who did not, 30% were inactive. During the median follow-up period of 13.4 years, there were 772 atherosclerotic events, 848 heart failure events, and 1,553 deaths, and 420 cardiovascular deaths. Compared with the participants in the lowest MVPA quartile, the highest quartile had a lower risk of atherosclerotic events (HR, 0.64 [95% CI, 0.51-0.79]), incident heart failure (HR, 0.71 [95% CI, 0.58-0.87]), and all-cause and cardiovascular death (HRs of 0.54 [95% CI, 0.46-0.63] and 0.47 [95% CI, 0.35-0.64], respectively). The findings were similar for analyses evaluating recommended level of physical activity. LIMITATIONS: Self-reported physical activity may result in some degree of misclassification. CONCLUSIONS: Higher self-reported physical activity was associated with lower risk of cardiovascular events and mortality in CKD patients, which may have important implications for clinical practice and the design of interventional studies. PLAIN-LANGUAGE SUMMARY: In this long-term study of 3,926 adults with chronic kidney disease, we found that individuals with higher levels of physical activity were less likely to experience an atherosclerotic event (for example, a heart attack, stroke, or peripheral arterial disease), new-onset heart failure, and death as compared with those with lower levels of physical activity. The findings were similar for the analyses evaluating adherence to guideline-recommended level of physical activity (that is, for more than 150 minutes per week), and they strengthen the evidence supporting the current guideline recommendations.

Coronary Artery Radial Deformation and Velocity in Native and Stented Arteries.

Introduction: Coronary arteries are exposed to a variety of complex biomechanical forces during a normal cardiac cycle. These forces have the potential to contribute to coronary stent failure. Recent advances in stent design allow for the transmission of native pulsatile biomechanical forces in the stented vessel. However, there is a significant lack of evidence in a human model to measure vessel motion in native coronary arteries and stent conformability. Thus, we aimed to characterize and define coronary artery radial deformation and the effect of stent implantation on arterial deformation. Materials and Methods: Intravascular ultrasound (IVUS) pullback DICOM images were obtained from human coronary arteries using a coronary ultrasound catheter. Using two-dimensional speckle tracking, coronary artery radial deformation was defined as the inward and outward displacement (mm) and velocity (cm/s) of the arterial wall during the cardiac cycle. These deformation values were obtained in native and third-generation drug-eluting stented artery segments. Results: A total of 20 coronary artery segments were independently analyzed pre and poststent implantation for a total of 40 IVUS runs. Stent implantation impacted the degree of radial deformation and velocity. Mean radial deformation in native coronary arteries was 0.1230 mm ± 0.0522 mm compared to 0.0775 mm ± 0.0376 mm in stented vessels (p=0.0031). Mean radial velocity in native coronary arteries was 0.1194 cm/s ± 0.0535 cm/s compared to 0.0840 cm/s ± 0.0399 cm/s in stented vessels (p=0.0228). Conclusion: In this in vivo analysis of third-generation stents, stent implantation attenuates normal human coronary deformation during the cardiac cycle. The implications of these findings on stent failure and improved clinical outcomes require further investigation.

A quantitative gain-independent assessment of the left atrial appendage as a method of thromboembolic risk stratification.

BACKGROUND: Visual assessment of the left atrial appendage (LAA) by echocardiography for the presence of thrombus is inherently qualitative. However, whether quantitative assessments can provide increased value over qualitative assessment has not been thoroughly examined. METHODS: One hundred and thirty-eight patients (mean age 59 ± 13 years, 70% male) undergoing transesophageal echocardiography prior to pulmonary vein isolation or electrical cardioversion were retrospectively studied. LAA were examined by two expert readers and identified as thrombus, sludge, spontaneous echocardiograph contrast, or normal. LAA were then separately examined to calculate a gain-independent ratio between the average pixel density of the LAA cavity and that of the LAA wall (C/W ratio). RESULTS: C/W ratio was significantly related with qualitative LAA analysis (p < 0.0001) and with thromboembolic events (OR 1.60, 95% CI 1.095-2.347, p = 0.02). The C/W ratio (AUC 0.73, 95% CI 0.60-0.86) was a reliable predictor for future thromboembolic events when compared to expert reader LAA assessment (Expert Reader 1 AUC = 0.72, 95% CI 0.53-0.90; Expert Reader 2 AUC = 0.69). CONCLUSIONS: The C/W ratio may be a complementary method to adjudicate thromboembolic risk in patients with AF that is readily quantifiable at time of TEE.

Beta-Blocker Dose Stratifies Mortality Risk in a Racially Diverse Heart Failure Population.

Heart failure (HF) is highly prevalent and a major cause of death in the United States. The effect of HF medications on survival has been predicted by validated models studied in populations predominantly of European descent. This study aimed to identify medications associated with survival in a racially diverse HF population. Patients with HF were recruited and followed from 2001 to 2015. Data were collected from electronic health records and the Social Security Death Index. The primary analysis tested the association between medication dose and all-cause mortality, with a secondary analysis assessing the composite outcome of death or cardiac-related hospitalization. Circulating concentration of the fibrotic marker procollagen type III N-terminal peptide (PIIINP) was also compared with medication doses in patients with concentrations available. The study population consisted of 337 patients, of which 25.2% died and 46% were hospitalized. Increased beta-blocker (BB) dose was significantly associated with survival in the base model [hazard ratio (HR) = 0.71, P = 0.017] and marginally associated in the comprehensive model (HR = 0.75, P = 0.068). BB dose was also associated with decreased risk of the composite end point in the base model (HR = 0.80, P = 0.029) and to a lesser extent in the comprehensive model (HR = 0.83, P = 0.085). Furthermore, increased BB dose was inversely associated with circulating PIIINP concentration (P = 0.041). In conclusion, our study highlights the importance of BB dose escalation for survival and decreased hospitalization in patients with HF, regardless of race or HF type. It also suggests that benefits observed with high-dose BBs could be mediated, at least in part, by decreased cardiac fibrosis.

Coronary artery rotation in native and stented porcine coronary arteries.

INTRODUCTION: Coronary arteries are exposed to several complex biomechanical forces during the cardiac cycle. These biomechanical forces potentially contribute to both native coronary artery disease, development of atherosclerosis and eventual stent failure. The aim of the present study was to characterize and define coronary artery axial rotation and the effect of stent implantation on this biomechanical factor. METHODS: Intravascular ultrasound (IVUS) images were obtained from porcine coronary arteries and analyzed in ultrasound analysis software used to evaluate myocardial strain and torsion in echocardiography. In this study the software was utilized for a novel application to evaluate coronary artery rotation and time-to-peak (TTP) rotation in porcine coronary arteries. Clockwise (CW) and counterclockwise (CCW) rotation of coronary arteries during the cardiac cycle and (TTP) rotation were measured. RESULTS: A total of 11 (4 LAD, 4 LCX, 3 RCA) coronary artery segments were independently analyzed pre- and post-stent implantation for a total of 22 IVUS runs. CW and CCW rotation and TTP varied widely within coronary artery segments and between different coronary arteries. Stent implantation impacted degree, direction and TTP of coronary rotation. Measurement reliability was assessed and the intraclass correlation coefficient for maximum average CCW was 0.990 (95% confidence interval 0.980-0.996, P < 0.0001), indicating excellent agreement. CONCLUSIONS: Coronary arteries display wide spectrum of CW and CCW rotation during the cardiac cycle. Coronary stents impact the degree and direction of coronary artery rotation. The implications of these findings on development of atherosclerosis and stent failure require further investigation.

Outcomes of a Pharmacist-Managed Heart Failure Medication Titration Assistance Clinic.

BACKGROUND: National guidelines recommend angiotensin-converting enzyme (ACE) inhibitors or angiotensin-receptor blockers (ARBs) and ß-blockers (BBs) at target doses for morbidity and mortality benefits in heart failure with reduced ejection fraction (HFrEF); regardless, titration of these therapies in practice remains suboptimal. We implemented an outpatient pharmacist-managed HFrEF medication titration assistance clinic (MTAC) at one institution to improve titration for general cardiology (GC) patients. OBJECTIVE: To evaluate MTAC impact by determining the proportion of patients on target or maximum tolerated ACE inhibitor/ARB and BB doses. METHODS: A retrospective chart review of adult patients with documented ejection fraction ≤40% managed in the MTAC or GC from 2011 to 2013 was conducted. HFrEF medication regimens were collected at initial visit and months 1, 2, 3, 6, 9, and 12 to assess titration. Target doses were defined per guideline or dose at which ejection fraction recovered during the study. Maximum tolerated doses were defined as the highest dose patients tolerated without physiological limitations. RESULTS: Of 148 patients, the MTAC managed 51 and GC managed 97. At baseline, 90% of MTAC versus 82% of GC patients were prescribed ACE inhibitors/ARBs and BBs. In the MTAC, 4% were at target or maximum tolerated doses compared with 32% of GC patients ( P < 0.001). At 12 months, 95% of patients in the MTAC and 87% in GC were prescribed ACE inhibitors/ARBs and BBs. Of those prescribed ACE inhibitors/ARBs and BBs, 64% in the MTAC versus 40% in GC reached target or maximum tolerated doses ( P = 0.01). CONCLUSIONS: The pharmacist-managed MTAC increased the proportion of patients on optimal HFrEF therapies and are a resource for GC patients.

Left Ventricular global longitudinal strain predicts heart failure readmission in acute decompensated heart failure.

BACKGROUND: The goal of this study was to determine if left ventricular (LV) global longitudinal strain (GLS) predicts heart failure (HF) readmission in patients with acute decompensated heart failure. METHODS AND RESULTS: Two hundred ninety one patients were enrolled at the time of admission for acute decompensated heart failure between January 2011 and September 2013. Left ventricle global longitudinal strain (LV GLS) by velocity vector imaging averaged from 2, 3 and 4-chamber views could be assessed in 204 out of 291 (70%) patients. Mean age was 63.8 ± 15.2 years, 42% of the patients were males and 78% were African American or Hispanic. Patients were followed until the first HF hospital readmission up to 44 months. Patients were grouped into quartiles on the basis of LV GLS. Kaplan-Meier curves showed significantly higher readmission rates in patients with worse LV GLS (log-rank p < 0.001). After adjusting for age, sex, history of ischemic heart disease, dementia, New York Heart Association class, LV ejection fraction, use of angiotensin converting enzyme inhibitors or angiotensin receptor blockers, systolic and diastolic blood pressure on admission and sodium level on admission, worse LV GLS was the strongest predictor of recurrent HF readmission (p < 0.001). The ejection fraction was predictive of readmission in univariate, but not in multivariate analysis. CONCLUSION: LV GLS is an independent predictor of HF readmission after acute decompensated heart failure with a higher risk of readmission in case of progressive worsening of LV GLS, independent of the ejection fraction.

Vitamin D Attenuates Left Atrial Volume Changes in African American Males with Obesity and Prediabetes.

Vitamin D deficiency is common among African Americans in the United States and is associated with increased cardiovascular disease risk. In this study, prediabetic African American males who were found to be vitamin D-deficient were randomized to vitamin D supplementation and assessed for changes in left atrial (LA) volume. Prediabetic African American males who were vitamin D-deficient (25(OH)D: 5.0-29 ng/mL) were randomized to high-dose ergocalciferol or placebo. Echocardiography was performed at baseline and at 1 year. Ejection fraction (EF), septal and posterior wall thickness, LA area, LA length, LA volume, E, A, septal and lateral e' and a', deceleration time, and isovolumetric relaxation time were collected. Eighty-one of 158 (51%) subjects received vitamin D2 . Baseline characteristics were similar among both groups. In the placebo group, left atrial volume significantly increased on follow-up (LA volume increased 6.3 mL, P = 0.0025). Compared with placebo group, the treatment group with ergocalciferol had attenuated increases in left atrial volume (LA volume increased 2.6 mL, P = 0.29). Changes in left atrial volume persisted when indexed to body surface area. There was no significant difference in other diastolic parameters and blood pressure between groups. In conclusion, vitamin D-deficient prediabetic African American males who were treated with high-dose vitamin D2 were found to have attenuated increases in left atrial volume compared with controls over 12-month follow-up.

Novel echocardiographic pixel intensity quantification method for differentiating transthyretin cardiac amyloidosis from light chain cardiac amyloidosis and other phenocopies.

AIMS: Differentiating cardiac amyloidosis (CA) subtypes is important considering the significantly different therapies for transthyretin (ATTR)-CA and light chain (AL)-CA. Therefore, an echocardiographic method to distinguish ATTR-CA from AL-CA would provide significant value. We assessed a novel echocardiographic pixel intensity method to quantify myocardial calcification to differentiate ATTR-CA from phenocopies of CA and from AL-CA, specifically. METHODS AND RESULTS: 167 patients with ATTR-CA (n=53), AL-CA (n=32), hypertrophic cardiomyopathy (n=37), and advanced chronic kidney disease (n=45) were retrospectively evaluated. The septal reflectivity ratio (SRR) was measured as the average pixel intensity of the visible anterior septal wall divided by the average pixel intensity of the visible posterior lateral wall. SRR and other myocardial strain-based echocardiographic measures were evaluated with receiver operator characteristic analysis to evaluate accuracy in distinguishing ATTR-CA from AL-CA and other forms of left ventricular hypertrophy. Mean septal reflectivity ratio (SRR) was significantly higher in the ATTR-CA cohort compared to the other cohorts (p <0.001). SRR demonstrated the largest AUC (0.91, p<0.0001) for distinguishing ATTR from all other cohorts and specifically for distinguishing ATTR-CA from AL-CA (AUC=0.90, p<0.0001, specificity 96%, sensitivity 63%). There was excellent inter- and intra-operator reproducibility with an ICC of 0.91 (p <0.001) and 0.89 (p <0.001), respectively. CONCLUSION: The SRR is a reproducible and robust parameter for differentiating ATTR-CA from other phenocopies of CA and specifically ATTR-CA from AL-CA.

Gut microbiota, blood metabolites, and left ventricular diastolic dysfunction in US Hispanics/Latinos.

BACKGROUND: Left ventricular diastolic dysfunction (LVDD) is an important precursor of heart failure (HF), but little is known about its relationship with gut dysbiosis and microbial-related metabolites. By leveraging the multi-omics data from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), a study with population at high burden of LVDD, we aimed to characterize gut microbiota associated with LVDD and identify metabolite signatures of gut dysbiosis and incident LVDD. RESULTS: We included up to 1996 Hispanic/Latino adults (mean age: 59.4 years; 67.1% female) with comprehensive echocardiography assessments, gut microbiome, and blood metabolome data. LVDD was defined through a composite criterion involving tissue Doppler assessment and left atrial volume index measurements. Among 1996 participants, 916 (45.9%) had prevalent LVDD, and 212 out of 594 participants without LVDD at baseline developed incident LVDD over a median 4.3 years of follow-up. Using multivariable-adjusted analysis of compositions of microbiomes (ANCOM-II) method, we identified 7 out of 512 dominant gut bacterial species (prevalence > 20%) associated with prevalent LVDD (FDR-q < 0.1), with inverse associations being found for Intestinimonas_massiliensis, Clostridium_phoceensis, and Bacteroide_coprocola and positive associations for Gardnerella_vaginali, Acidaminococcus_fermentans, Pseudomonas_aeruginosa, and Necropsobacter_massiliensis. Using multivariable adjusted linear regression, 220 out of 669 circulating metabolites with detection rate > 75% were associated with the identified LVDD-related bacterial species (FDR-q < 0.1), with the majority being linked to Intestinimonas_massiliensis, Clostridium_phoceensis, and Acidaminococcus_fermentans. Furthermore, 46 of these bacteria-associated metabolites, mostly glycerophospholipids, secondary bile acids, and amino acids, were associated with prevalent LVDD (FDR-q < 0.1), 21 of which were associated with incident LVDD (relative risk ranging from 0.81 [p = 0.001, for guanidinoacetate] to 1.25 [p = 9 × 10-5, for 1-stearoyl-2-arachidonoyl-GPE (18:0/20:4)]). The inclusion of these 21 bacterial-related metabolites significantly improved the prediction of incident LVDD compared with a traditional risk factor model (the area under the receiver operating characteristic curve [AUC] = 0.73 vs 0.70, p = 0.001). Metabolite-based proxy association analyses revealed the inverse associations of Intestinimonas_massilliensis and Clostridium_phoceensis and the positive association of Acidaminococcus_fermentans with incident LVDD. CONCLUSION: In this study of US Hispanics/Latinos, we identified multiple gut bacteria and related metabolites linked to LVDD, suggesting their potential roles in this preclinical HF entity. Video Abstract.

Application of a Novel Two-Dimensional Echocardiographic Calcium Quantification Method to Assess All Severities of Aortic Stenosis.

BACKGROUND: Aortic valve (AV) calcification (AVC) is a strong predictor of aortic stenosis (AS) severity. The two-dimensional AVC (2D-AVC) ratio, a gain-independent ratio composed of the average pixel density of the AV and the aortic annulus, has previously shown strong correlations with two-dimensional (2D) echocardiographic hemodynamic parameters for severe AS and AVC by cardiac computed tomography. We hypothesize that the 2D-AVC ratio correlates with hemodynamic parameters in all severities of AS. METHODS: A total of 285 patients with a normal AV (n = 49), aortic sclerosis (n = 75), or mild (n = 38), moderate (n = 72), or severe (n = 51) AS undergoing 2D echocardiography were retrospectively evaluated, and the 2D-AVC ratios were correlated to mean AV gradient, peak AV velocity, AV area, and dimensionless index. The 2D-AVC ratios of various AS severities were compared against each other via area under the curve (AUC) analysis. RESULTS: The 2D-AVC ratio is strongly correlated with mean AV gradient (r = 0.79, P < .0001) and peak AV velocity (r = 0.78, P < .0001). There was moderate correlation with the AV area (r = -0.58, P < .0001) and dimensionless index (r = -0.67, P < .0001) across all AS severities. The 2D-AVC ratio also distinguished nonmoderate AS (mild AS + normal AV) from moderate or greater (moderate + severe) AS (AUC = 0.93) and moderate versus severe AS (AUC = 0.88). CONCLUSION: The 2D-AVC ratio exhibits moderate to strong correlation with 2D echocardiographic hemodynamic parameters across all severities of AS.

Fully Automated Artificial Intelligence Assessment of Aortic Stenosis by Echocardiography.

BACKGROUND: Aortic stenosis (AS) is a common form of valvular heart disease, present in over 12% of the population age 75 years and above. Transthoracic echocardiography (TTE) is the first line of imaging in the adjudication of AS severity but is time-consuming and requires expert sonographic and interpretation capabilities to yield accurate results. Artificial intelligence (AI) technology has emerged as a useful tool to address these limitations but has not yet been applied in a fully hands-off manner to evaluate AS. Here, we correlate artificial neural network measurements of key hemodynamic AS parameters to experienced human reader assessment. METHODS: Two-dimensional and Doppler echocardiographic images from patients with normal aortic valves and all degrees of AS were analyzed by an artificial neural network (Us2.ai) with no human input to measure key variables in AS assessment. Trained echocardiographers blinded to AI data performed manual measurements of these variables, and correlation analyses were performed. RESULTS: Our cohort included 256 patients with an average age of 67.6 ± 9.5 years. Across all AS severities, AI closely matched human measurement of aortic valve peak velocity (r = 0.97, P < .001), mean pressure gradient (r = 0.94, P < .001), aortic valve area by continuity equation (r = 0.88, P < .001), stroke volume index (r = 0.79, P < .001), left ventricular outflow tract velocity-time integral (r = 0.89, P < .001), aortic valve velocity-time integral (r = 0.96, P < .001), and left ventricular outflow tract diameter (r = 0.76, P < .001). CONCLUSIONS: Artificial neural networks have the capacity to closely mimic human measurement of all relevant parameters in the adjudication of AS severity. Application of this AI technology may minimize interscan variability, improve interpretation and diagnosis of AS, and allow for precise and reproducible identification and management of patients with AS.

Association of Vitamin K Status with Arterial Calcification and Stiffness in Chronic Kidney Disease: The Chronic Renal Insufficiency Cohort.

Background: Arterial calcification and stiffness are common in people with chronic kidney disease (CKD). Higher vitamin K status has been associated with less arterial calcification and stiffness in CKD in cross-sectional studies. Objectives: To determine the association of vitamin K status with coronary artery calcium (CAC) and arterial stiffness [pulse wave velocity (PWV)] at baseline and over 2-4 follow-up years in adults with mild-to-moderate CKD. Methods: Participants (n = 2722) were drawn from the well-characterized Chronic Renal Insufficiency Cohort. Two vitamin K status biomarkers, plasma phylloquinone and plasma dephospho-uncarboxylated matrix gla protein [(dp)ucMGP], were measured at baseline. CAC and PWV were measured at baseline and over 2-4 y of follow-up. Differences across vitamin K status categories in CAC prevalence, incidence, and progression (defined as ≥100 Agatston units/y increase) and PWV at baseline and over follow-up were evaluated using multivariable-adjusted generalized linear models. Results: CAC prevalence, incidence, and progression did not differ across plasma phylloquinone categories. Moreover, CAC prevalence and incidence did not differ according to plasma (dp)ucMGP concentration. Compared with participants with the highest (dp)ucMGP (≥450 pmol/L), those in the middle category (300-449 pmol/L) had a 49% lower rate of CAC progression (incidence rate ratio: 0.51; 95% CI: 0.33, 0.78). However, CAC progression did not differ between those with the lowest (<300 pmol/L) and those with the highest plasma (dp)ucMGP concentration (incidence rate ratio: 0.82; 95% CI: 0.56, 1.19). Neither vitamin K status biomarker was associated with PWV at baseline or longitudinally. Conclusions: Vitamin K status was not consistently associated with CAC or PWV in adults with mild-to-moderate CKD.