Novel Role for Cardiolipin as a Target of Therapy to Mitigate Myocardial Injury Caused by Venoarterial Extracorporeal Membrane Oxygenation

BACKGROUND

Cardiolipin is a mitochondrial-specific phospholipid that maintains integrity of the electron transport chain (ETC) and plays a central role in myocardial ischemia/reperfusion injury. Tafazzin is an enzyme that is required for cardiolipin maturation. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) use to provide hemodynamic support for acute myocardial infarction has grown exponentially, is associated with poor outcomes, and is under active clinical investigation, yet the mechanistic effect of VA-ECMO on myocardial damage in acute myocardial infarction remains poorly understood. We hypothesized that VA-ECMO acutely depletes myocardial cardiolipin and exacerbates myocardial injury in acute myocardial infarction.

METHODS

We examined cardiolipin and tafazzin levels in human subjects with heart failure and healthy swine exposed to VA-ECMO and used a swine model of closed-chest myocardial ischemia/reperfusion injury to evaluate the effect of VA-ECMO on cardiolipin expression, myocardial injury, and mitochondrial function.

RESULTS

Cardiolipin and tafazzin levels are significantly reduced in the left ventricles of individuals requiring VA-ECMO compared with individuals without VA-ECMO before heart transplantation. Six hours of exposure to VA-ECMO also decreased left ventricular levels of cardiolipin and tafazzin in healthy swine compared with sham controls. To explore whether cardiolipin depletion by VA-ECMO increases infarct size, we performed left anterior descending artery occlusion for a total of 120 minutes followed by 180 minutes of reperfusion in adult swine in the presence and absence of MTP-131, an amphipathic molecule that interacts with cardiolipin to stabilize the inner mitochondrial membrane. Compared with reperfusion alone, VA-ECMO activation beginning after 90 minutes of left anterior descending artery occlusion increased infarct size (36±8% versus 48±7%; P<0.001). VA-ECMO also decreased cardiolipin and tafazzin levels, disrupted mitochondrial integrity, reduced electron transport chain function, and promoted oxidative stress. Compared with reperfusion alone or VA-ECMO before reperfusion, delivery of MTP-131 before VA-ECMO activation reduced infarct size (22±8%; P=0.03 versus reperfusion alone and P<0.001 versus VA-ECMO alone). MTP-131 restored cardiolipin and tafazzin levels, stabilized mitochondrial function, and reduced oxidative stress in the left ventricle.

CONCLUSIONS

We identified a novel mechanism by which VA-ECMO promotes myocardial injury and further identify cardiolipin as an important target of therapy to reduce infarct size and to preserve mitochondrial function in the setting of VA-ECMO for acute myocardial infarction.

MicroRNA-409-3p/BTG2 signaling axis improves impaired angiogenesis and wound healing in obese mice

Wound healing is facilitated by neoangiogenesis, a complex process that is essential to tissue repair in response to injury. MicroRNAs are small, noncoding RNAs that can regulate the wound healing process including stimulation of impaired angiogenesis that is associated with type-2 diabetes (T2D). Expression of miR-409-3p was significantly increased in the nonhealing skin wounds of patients with T2D compared to the non-wounded normal skin, and in the skin of a murine model with T2D. In response to high glucose, neutralization of miR-409-3p markedly improved EC growth and migration in human umbilical vein endothelial cells (HUVECs), promoted wound closure and angiogenesis as measured by increased CD31 in human skin organoids, while overexpression attenuated EC angiogenic responses. Bulk mRNA-Seq transcriptomic profiling revealed BTG2 as a target of miR-409-3p, where overexpression of miR-409-3p significantly decreased BTG2 mRNA and protein expression. A 3' untranslated region (3'-UTR) luciferase assay of BTG2 revealed decreased luciferase activity with overexpression of miR-409-3p, while inhibition had opposite effects. Mechanistically, in response to high glucose, miR-409-3p deficiency in ECs resulted in increased mTOR phosphorylation, meanwhile BTG-anti-proliferation factor 2 (BTG2) silencing significantly decreased mTOR phosphorylation. Endothelial-specific and tamoxifen-inducible miR-409-3p knockout mice (MiR-409IndECKO ) with hyperglycemia that underwent dorsal skin wounding showed significant improvement of wound closure, increased blood flow, granulation tissue thickness (GTT), and CD31 that correlated with increased BTG2 expression. Taken together, our results show that miR-409-3p is a critical mediator of impaired angiogenesis in diabetic skin wound healing.

Diagnostic accuracy of point-of-care ultrasound with artificial intelligence-assisted assessment of left ventricular ejection fraction

Focused cardiac ultrasound (FoCUS) is becoming standard practice in a wide spectrum of clinical settings. There is limited data evaluating the real-world use of FoCUS with artificial intelligence (AI). Our objective was to determine the accuracy of FoCUS AI-assisted left ventricular ejection fraction (LVEF) assessment and compare its accuracy between novice and experienced users. In this prospective, multicentre study, participants requiring a transthoracic echocardiogram (TTE) were recruited to have a FoCUS done by a novice or experienced user. The AI-assisted device calculated LVEF at the bedside, which was subsequently compared to TTE. 449 participants were enrolled with 424 studies included in the final analysis. The overall intraclass coefficient was 0.904, and 0.921 in the novice (n = 208) and 0.845 in the experienced (n = 216) cohorts. There was a significant bias of 0.73% towards TTE (p = 0.005) with a level of agreement of 11.2%. Categorical grading of LVEF severity had excellent agreement to TTE (weighted kappa = 0.83). The area under the curve (AUC) was 0.98 for identifying an abnormal LVEF (<50%) with a sensitivity of 92.8%, specificity of 92.3%, negative predictive value (NPV) of 0.97 and a positive predictive value (PPV) of 0.83. In identifying severe dysfunction (<30%) the AUC was 0.99 with a sensitivity of 78.1%, specificity of 98.0%, NPV of 0.98 and PPV of 0.76. Here we report that FoCUS AI-assisted LVEF assessments provide highly reproducible LVEF estimations in comparison to formal TTE. This finding was consistent among senior and novice echocardiographers suggesting applicability in a variety of clinical settings.

Clinical impact of pulmonary artery catheter in patients with cardiogenic shock: A systematic review and meta-analysis

BACKGROUND

The clinical utility of the pulmonary artery catheter (PAC) for the management of cardiogenic shock (CS) remains controversial. We performed a systematic review and meta-analysis exploring the association between PAC use and mortality among patients with CS.

METHODS

Published studies of patients with CS treated with or without PAC hemodynamic guidance were retrieved from MEDLINE and PubMed databases from January 1, 2000, to December 31, 2021. The primary outcome was mortality, which was defined as a combination of in-hospital mortality and 30-day mortality. Secondary outcomes assessed 30-day and in-hospital mortality separately. To assess the quality of nonrandomized studies, the Newcastle-Ottawa Scale (NOS), a well-established scoring system was used. We analyzed outcomes for each study using NOS with a threshold value of >6, indicating high quality. We also performed analyses based on the countries of the studies conducted.

RESULTS

Six studies with a total of 930,530 patients with CS were analyzed. Of these, 85,769 patients were in the PAC-treated group, and 844,761 patients did not receive a PAC. PAC use was associated with a significantly lower risk of mortality (PAC: 4.6 % to 41.5 % vs control: 18.8 % to 51.0 %) (OR 0.63, 95 % CI: 0.41-0.97, I2 = 0.96). Subgroup analyses demonstrated no difference in the risk of mortality between NOS ≥ 6 studies and NOS < 6 studies (p-interaction = 0.57), 30-day and in-hospital mortality (p-interaction = 0.83), or the country of origin of studies (p-interaction = 0.08).

CONCLUSIONS

The use of PAC in patients with CS may be associated with decreased mortality. These data support the need for a randomized controlled trial testing the utility of PAC use in CS.

Rare Variant Genetics and Dilated Cardiomyopathy Severity: The DCM Precision Medicine Study

BACKGROUND

Dilated cardiomyopathy (DCM) can lead to advanced disease, defined herein as necessitating a durable left ventricular assist device or a heart transplant (LVAD/HT). DCM is known to have a genetic basis, but the association of rare variant genetics with advanced DCM has not been studied.

METHODS

We analyzed clinical and genetic sequence data from patients enrolled between 2016 and 2021 in the US multisite DCM Precision Medicine Study, which was a geographically diverse, multiracial, multiethnic cohort. Clinical evaluation included standardized patient interview and medical record query forms. DCM severity was classified into 3 groups: patients with advanced disease with LVAD/HT; patients with an implantable cardioverter defibrillator (ICD) only; or patients with no ICD or LVAD/HT. Rare variants in 36 DCM genes were classified as pathogenic or likely pathogenic or variants of uncertain significance. Confounding factors we considered included demographic characteristics, lifestyle factors, access to care, DCM duration, and comorbidities. Crude and adjusted associations between DCM severity and rare variant genetic findings were assessed using multinomial models with generalized logit link.

RESULTS

Patients' mean (SD) age was 51.9 (13.6) years; 42% were of African ancestry, 56% were of European ancestry, and 44% were female. Of 1198 patients, 347 had LVAD/HT, 511 had an ICD, and 340 had no LVAD/HT or ICD. The percentage of patients with pathogenic or likely pathogenic variants was 26.2%, 15.9%, and 15.0% for those with LVAD/HT, ICD only, or neither, respectively. After controlling for sociodemographic characteristics and comorbidities, patients with DCM with LVAD/HT were more likely than those without LVAD/HT or ICD to have DCM-related pathogenic or likely pathogenic rare variants (odds ratio, 2.3 [95% CI, 1.5-3.6]). The association did not differ by ancestry. Rare variant genetic findings were similar between patients with DCM with an ICD and those without LVAD/HT or ICD.

CONCLUSIONS

Advanced DCM was associated with higher odds of rare variants in DCM genes adjudicated as pathogenic or likely pathogenic, compared with individuals with less severe DCM. This finding may help assess the risk of outcomes in management of patients with DCM and their at-risk family members.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03037632.

Genetic Architecture of Dilated Cardiomyopathy in Individuals of African and European Ancestry

Importance

Black patients with dilated cardiomyopathy (DCM) have increased familial risk and worse outcomes than White patients, but most DCM genetic data are from White patients.

Objective

To compare the rare variant genetic architecture of DCM by genomic ancestry within a diverse population of patients with DCM.

Design

Cross-sectional study enrolling patients with DCM who self-identified as non-Hispanic Black, Hispanic, or non-Hispanic White from June 7, 2016, to March 15, 2020, at 25 US advanced heart failure programs. Variants in 36 DCM genes were adjudicated as pathogenic, likely pathogenic, or of uncertain significance.

Exposure

Presence of DCM.

Main Outcomes and Measures

Variants in DCM genes classified as pathogenic/likely pathogenic/uncertain significance and clinically actionable (pathogenic/likely pathogenic).

Results

A total of 505, 667, and 26 patients with DCM of predominantly African, European, or Native American genomic ancestry, respectively, were included. Compared with patients of European ancestry, a lower percentage of patients of African ancestry had clinically actionable variants (8.2% [95% CI, 5.2%-11.1%] vs 25.5% [95% CI, 21.3%-29.6%]), reflecting the lower odds of a clinically actionable variant for those with any pathogenic variant/likely pathogenic variant/variant of uncertain significance (odds ratio, 0.25 [95% CI, 0.17-0.37]). On average, patients of African ancestry had fewer clinically actionable variants in TTN (difference, -0.09 [95% CI, -0.14 to -0.05]) and other genes with predicted loss of function as a disease-causing mechanism (difference, -0.06 [95% CI, -0.11 to -0.02]). However, the number of pathogenic variants/likely pathogenic variants/variants of uncertain significance was more comparable between ancestry groups (difference, -0.07 [95% CI, -0.22 to 0.09]) due to a larger number of non-TTN non-predicted loss of function variants of uncertain significance, mostly missense, in patients of African ancestry (difference, 0.15 [95% CI, 0.00-0.30]). Published clinical case-based evidence supporting pathogenicity was less available for variants found only in patients of African ancestry (P < .001).

Conclusion and Relevance

Patients of African ancestry with DCM were less likely to have clinically actionable variants in DCM genes than those of European ancestry due to differences in genetic architecture and a lack of representation of African ancestry in clinical data sets.

Screening for Dilated Cardiomyopathy in At-Risk First-Degree Relatives

BACKGROUND

Cardiovascular screening is recommended for first-degree relatives (FDRs) of patients with dilated cardiomyopathy (DCM), but the yield of FDR screening is uncertain for DCM patients without known familial DCM, for non-White FDRs, or for DCM partial phenotypes of left ventricular enlargement (LVE) or left ventricular systolic dysfunction (LVSD).

OBJECTIVES

This study examined the yield of clinical screening among reportedly unaffected FDRs of DCM patients.

METHODS

Adult FDRs of DCM patients at 25 sites completed screening echocardiograms and ECGs. Mixed models accounting for site heterogeneity and intrafamilial correlation were used to compare screen-based percentages of DCM, LVSD, or LVE by FDR demographics, cardiovascular risk factors, and proband genetics results.

RESULTS

A total of 1,365 FDRs were included, with a mean age of 44.8 ± 16.9 years, 27.5% non-Hispanic Black, 9.8% Hispanic, and 61.7% women. Among screened FDRs, 14.1% had new diagnoses of DCM (2.1%), LVSD (3.6%), or LVE (8.4%). The percentage of FDRs with new diagnoses was higher for those aged 45 to 64 years than 18 to 44 years. The age-adjusted percentage of any finding was higher among FDRs with hypertension and obesity but did not differ statistically by race and ethnicity (16.2% for Hispanic, 15.2% for non-Hispanic Black, and 13.1% for non-Hispanic White) or sex (14.6% for women and 12.8% for men). FDRs whose probands carried clinically reportable variants were more likely to be identified with DCM.

CONCLUSIONS

Cardiovascular screening identified new DCM-related findings among 1 in 7 reportedly unaffected FDRs regardless of race and ethnicity, underscoring the value of clinical screening in all FDRs.

Effectiveness of the Family Heart Talk Communication Tool in Improving Family Member Screening for Dilated Cardiomyopathy: Results of a Randomized Trial

BACKGROUND

Managing disease risk among first-degree relatives of probands diagnosed with a heritable disease is central to precision medicine. A critical component is often clinical screening, which is particularly important for conditions like dilated cardiomyopathy (DCM) that remain asymptomatic until severe disease develops. Nonetheless, probands are frequently ill-equipped to disseminate genetic risk information that motivates at-risk relatives to complete recommended clinical screening. An easily implemented remedy for this key issue has been elusive.

METHODS

The DCM Precision Medicine Study developed Family Heart Talk, a booklet designed to help probands with DCM communicate genetic risk and the need for cardiovascular screening to their relatives. The effectiveness of the Family Heart Talk booklet in increasing cardiovascular clinical screening uptake among first-degree relatives was assessed in a multicenter, open-label, cluster-randomized, controlled trial. The primary outcome measured in eligible first-degree relatives was completion of screening initiated within 12 months after proband enrollment. Because probands randomized to the intervention received the booklet at the enrollment visit, eligible first-degree relatives were limited to those who were alive the day after proband enrollment and not enrolled on the same day as the proband.

RESULTS

Between June 2016 and March 2020, 1241 probands were randomized (1:1) to receive Family Heart Talk (n=621) or not (n=620) within strata defined by site and self-identified race/ethnicity (non-Hispanic Black, non-Hispanic White, or Hispanic). Final analyses included 550 families (n=2230 eligible first-degree relatives) in the Family Heart Talk arm and 561 (n=2416) in the control arm. A higher percentage of eligible first-degree relatives completed screening in the Family Heart Talk arm (19.5% versus 16.0%), and the odds of screening completion among these first-degree relatives were higher in the Family Heart Talk arm after adjustment for proband randomization stratum, sex, and age quartile (odds ratio, 1.30 [1-sided 95% CI, 1.08-∞]). A prespecified subgroup analysis did not find evidence of heterogeneity in the adjusted intervention odds ratio across race/ethnicity strata (P=0.90).

CONCLUSIONS

Family Heart Talk, a booklet that can be provided to patients with DCM by clinicians with minimal additional time investment, was effective in increasing cardiovascular clinical screening among first-degree relatives of these patients.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03037632.

Do Patients With Non-Viable Myocardium From Ischemic Cardiomyopathy Benefit From Revascularization? A Systematic Review And Meta-Analysis

BACKGROUND

Myocardial viability assessment is used to select patients who will derive the greatest benefit from revascularization. It remains controversial whether revascularization only benefits patients with ischemic cardiomyopathy who have viable myocardium. The objective of this meta-analysis was to compare mortality between patients with ischemic cardiomyopathy and non-viable myocardium who underwent revascularization and those who underwent medical therapy alone.

METHODS

The MEDLINE database was searched using PubMed to retrieve studies published up to December 2021. Inclusion criteria were 1. studies that evaluated the impact of revascularization (revascularization group) versus medical therapy alone (control group) following myocardial viability assessment; 2. patients who had coronary artery disease that was amenable to coronary artery bypass grafting or percutaneous coronary intervention; and 3. patients who had non-viable myocardium. The main outcome measure was all-cause mortality.

RESULTS

A total of 12 studies were included, evaluating 1363 patients with non-viable myocardium, of whom 501 patients underwent revascularization and 862 patients received medical therapy alone. There was a significant reduction in all-cause mortality (RR 0.76, 95 % CI: 0.62-0.93, I² = 0) in the revascularization group compared to the control group. There was no association between the type of viability imaging modality and the risk of all-cause mortality (P-interaction = 0.58).

CONCLUSIONS

The findings of this meta-analysis suggest a benefit from revascularization compared to medical therapy in patients with ischemic cardiomyopathy despite the lack of myocardial viability.

Specialized Pro-Resolving Mediators Reduce Scarring After Cleft Lip Repair

Objective

Residual scarring after cleft lip repair surgery remains a challenge for both surgeons and patients and novel therapeutics are critically needed. The objective of this preclinical experimental study was to evaluate the impact of the methyl-ester of pro-resolving lipid mediator lipoxin A4 (LXA4-ME) on scarring in a novel rabbit model of cleft lip repair.

Methods

A defect of the lip was surgically created and repaired in eight six-week old New Zealand white rabbits to simulate human cleft lip scars. Rabbits were randomly assigned to topical application of PBS (control) or 1 ug of LXA4-ME (treatment). 42 days post surgery all animals were euthanized. Photographs of the cleft lip area defect and histologic specimens were evaluated. Multiple scar assessment scales were used to compare scarring.

Results

Animals treated with LXA4-ME exhibited lower Visual Scar Assessment scores compared to animals treated with PBS. Treatment with LXA4-ME resulted in a significant reduction of inflammatory cell infiltrate and density of collagen fibers. Control animals showed reduced 2D directional variance (orientation) of collagen fibers compared to animals treated with LXA4-ME demonstrating thicker and more parallel collagen fibers, consistent with scar tissue.

Conclusions

These data suggest that LXA4-ME limits scarring after cleft lip repair and improves wound healing outcomes in rabbits favoring the resolution of inflammation. Further studies are needed to explore the mechanisms that underlie the positive therapeutic impact of LXA4-ME on scarring to set the stage for future human clinical trials of LXA4-ME for scar prevention or treatment after cleft lip repair.

TTR variants in patients with dilated cardiomyopathy: An investigation of the DCM Precision Medicine Study

PURPOSE

The cardiac phenotype of hereditary transthyretin amyloidosis (hTTR) usually presents as a restrictive or hypertrophic cardiomyopathy, and, although rarely observed as dilated cardiomyopathy (DCM), TTR is routinely included in DCM genetic testing panels. However, the prevalence and phenotypes of TTR variants in patients with DCM have not been reported.

METHODS

Exome sequences of 729 probands with idiopathic DCM were analyzed for TTR and 35 DCM genes.

RESULTS

Rare TTR variants were identified in 2 (0.5%; 95% CI = 0.1%-1.8%) of 404 non-Hispanic White DCM probands; neither of them had features of hTTR. In 1 proband, a TTR His110Asn variant and a variant of uncertain significance in DSP were identified, and in the other proband, a TTR Val50Met variant known to cause hTTR and a likely pathogenic variant in FLNC were identified. The TTR Val142Ile variant was identified in 8 (3.0%) non-Hispanic Black probands, comparable with African/African American Genome Aggregation Database controls (OR = 1.01; 95% CI = 0.46-1.99).

CONCLUSION

Among the 729 DCM probands, 2 had rare TTR variants identified without the features of hTTR, and both had other plausible genetic causes of DCM. Moreover, the frequency of TTR Val142Ile was comparable to a control sample. These findings suggest that hTTR variants may have a limited role in patients with DCM without TTR-specific findings.

Altered intercellular communication and extracellular matrix signaling as a potential disease mechanism in human hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is considered a primary disorder of the sarcomere resulting in unexplained left ventricular hypertrophy but the paradoxical association of nonmyocyte phenotypes such as fibrosis, mitral valve anomalies and microvascular occlusion is unexplained. To understand the interplay between cardiomyocyte and nonmyocyte cell types in human HCM, single nuclei RNA-sequencing was performed on myectomy specimens from HCM patients with left ventricular outflow tract obstruction and control samples from donor hearts free of cardiovascular disease. Clustering analysis based on gene expression patterns identified a total of 34 distinct cell populations, which were classified into 10 different cell types based on marker gene expression. Differential gene expression analysis comparing HCM to Normal datasets revealed differences in sarcomere and extracellular matrix gene expression. Analysis of expressed ligand-receptor pairs across multiple cell types indicated profound alteration in HCM intercellular communication, particularly between cardiomyocytes and fibroblasts, fibroblasts and lymphocytes and involving integrin β1 and its multiple extracellular matrix (ECM) cognate ligands. These findings provide a paradigm for how sarcomere dysfunction is associated with reduced cardiomyocyte secretion of ECM ligands, altered fibroblast ligand-receptor interactions with other cell types and increased fibroblast to lymphocyte signaling, which can further alter the ECM composition and promote nonmyocyte phenotypes.

Validating an Idiopathic Dilated Cardiomyopathy Diagnosis Using Cardiovascular Magnetic Resonance: The Dilated Cardiomyopathy Precision Medicine Study

BACKGROUND

Coronary angiography to identify coronary artery disease has been foundational to distinguish the cause of dilated cardiomyopathy (DCM), including the assignment of idiopathic or ischemic cardiomyopathy. Late gadolinium enhancement (LGE) with cardiovascular magnetic resonance (CMR) has emerged as an approach to identify myocardial scar and identify etiology.

METHODS

The DCM Precision Medicine Study included patients with left ventricular dilation and dysfunction attributed to idiopathic DCM, after expert clinical review excluded ischemic or other cardiomyopathies. Ischemic cardiomyopathy was defined as coronary artery disease with >50% narrowing at angiography of ≥1 epicardial coronary artery. CMR was not required for study inclusion, but in a post hoc analysis of available CMR reports, patterns of LGE were classified as (1) no LGE, (2) ischemic-pattern LGE: subendocardial/transmural, (3) nonischemic LGE: midmyocardial/epicardial.

RESULTS

Of 1204 idiopathic DCM patients evaluated, 396 (32.9%) had a prior CMR study; of these, 327 (82.6% of 396) had LGE imaging (mean age 46 years; 53.2% male; 55.4% White); 178 of the 327 (54.4%) exhibited LGE, and 156 of the 178 had LGE consistent with idiopathic DCM. The remaining 22 had transmural or subendocardial LGE. Of these 22, coronary angiography was normal (13), showed luminal irregularities (3), a distant thrombus (1), coronary artery disease with <50% coronary artery narrowing (1), or was not available (4).

CONCLUSIONS

Of 327 probands enrolled in the DCM Precision Medicine Study cohort who had LGE-CMR data available, an ischemic-pattern of LGE was identified in 22 (6.7%), all of whom had idiopathic DCM as adjudicated by expert clinical review.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03037632.

Prevalence and Cumulative Risk of Familial Idiopathic Dilated Cardiomyopathy

Importance

Idiopathic dilated cardiomyopathy (DCM) aggregates in families, and early detection in at-risk family members can provide opportunity to initiate treatment prior to late-phase disease. Most studies have included only White patients, yet Black patients with DCM have higher risk of heart failure-related hospitalization and death.

Objective

To estimate the prevalence of familial DCM among DCM probands and the age-specific cumulative risk of DCM in first-degree relatives across race and ethnicity groups.

Design, Setting, and Participants

A family-based, cross-sectional study conducted by a multisite consortium of 25 US heart failure programs. Participants included patients with DCM (probands), defined as left ventricular systolic dysfunction and left ventricular enlargement after excluding usual clinical causes, and their first-degree relatives. Enrollment commenced June 7, 2016; proband and family member enrollment concluded March 15, 2020, and April 1, 2021, respectively.

Exposures

The presence of DCM in a proband.

Main Outcomes and Measures

Familial DCM defined by DCM in at least 1 first-degree relative; expanded familial DCM defined by the presence of DCM or either left ventricular enlargement or left ventricular systolic dysfunction without known cause in at least 1 first-degree relative.

Results

The study enrolled 1220 probands (median age, 52.8 years [IQR, 42.4-61.8]; 43.8% female; 43.1% Black and 8.3% Hispanic) and screened 1693 first-degree relatives for DCM. A median of 28% (IQR, 0%-60%) of living first-degree relatives were screened per family. The crude prevalence of familial DCM among probands was 11.6% overall. The model-based estimate of the prevalence of familial DCM among probands at a typical US advanced heart failure program if all living first-degree relatives were screened was 29.7% (95% CI, 23.5% to 36.0%) overall. The estimated prevalence of familial DCM was higher in Black probands than in White probands (difference, 11.3% [95% CI, 1.9% to 20.8%]) but did not differ significantly between Hispanic probands and non-Hispanic probands (difference, -1.4% [95% CI, -15.9% to 13.1%]). The estimated prevalence of expanded familial DCM was 56.9% (95% CI, 50.8% to 63.0%) overall. Based on age-specific disease status at enrollment, estimated cumulative risks in first-degree relatives at a typical US advanced heart failure program reached 19% (95% CI, 13% to 24%) by age 80 years for DCM and 33% (95% CI, 27% to 40%) for expanded DCM inclusive of partial phenotypes. The DCM hazard was higher in first-degree relatives of non-Hispanic Black probands than non-Hispanic White probands (hazard ratio, 1.89 [95% CI, 1.26 to 2.83]).

Conclusions and Relevance

In a US cross-sectional study, there was substantial estimated prevalence of familial DCM among probands and modeled cumulative risk of DCM among their first-degree relatives.

Trial Registration

ClinicalTrials.gov Identifier: NCT03037632.

Individualized interactomes for network-based precision medicine in hypertrophic cardiomyopathy with implications for other clinical pathophenotypes

Progress in precision medicine is limited by insufficient knowledge of transcriptomic or proteomic features in involved tissues that define pathobiological differences between patients. Here, myectomy tissue from patients with obstructive hypertrophic cardiomyopathy and heart failure is analyzed using RNA-Seq, and the results are used to develop individualized protein-protein interaction networks. From this approach, hypertrophic cardiomyopathy is distinguished from dilated cardiomyopathy based on the protein-protein interaction network pattern. Within the hypertrophic cardiomyopathy cohort, the patient-specific networks are variable in complexity, and enriched for 30 endophenotypes. The cardiac Janus kinase 2-Signal Transducer and Activator of Transcription 3-collagen 4A2 (JAK2-STAT3-COL4A2) expression profile informed by the networks was able to discriminate two hypertrophic cardiomyopathy patients with extreme fibrosis phenotypes. Patient-specific network features also associate with other important hypertrophic cardiomyopathy clinical phenotypes. These proof-of-concept findings introduce personalized protein-protein interaction networks (reticulotypes) for characterizing patient-specific pathobiology, thereby offering a direct strategy for advancing precision medicine.

Noninvasive Epidermal Metabolite Profiling

A buffer placed in brief contact in the skin was assayed by ¹H NMR spectroscopy. We found that this passive extraction of the skin surface yields abundant metabolites. Metabolites of the skin surface originate from a variety of sources, including the sweat gland, which produces lactate from the glucose received from its capillary bed. Little is known about how metabolites resident on and within the skin surface respond to a metabolic or hemodynamic perturbation. As a possible application of epidermal metabolite profiling, we asked whether metabolites extracted from the skin surface are indicative of heart failure. The levels of lactate and other molecules were significantly lower in patients in heart failure than in individuals who reported healthy heart function, possibly due to reduced blood flow to the sweat gland resulting in a lack of tissue perfusion. Most amino acids were unchanged in levels, except for glycine and serine that increased as a percentage of all amino acids. These results have the potential in the long term to help decide the extent to which a patient has heart failure for which objective measures are lacking. Moreover, the results suggest that epidermal metabolite profiling may be useful for other assessments of human health.

Associations between Circulating Lipids and Fat-Soluble Vitamins and Carotenoids in Healthy Overweight and Obese Men

Inconsistent associations between lipids and circulating markers of fat-soluble vitamin and carotenoid status have been reported. The aim of this hypothesis-generating study was to examine the contribution of the LC-MS-based lipidome, characterized by lipid class, carbon count, and the number of unsaturated bonds, to the interindividual variability in circulating concentrations of retinol, carotenoids, 25-hydroxyvitamin D3, α-tocopherol, γ-tocopherol, and phylloquinone in 35 overweight and obese, but healthy men. A sparse partial least-squares method was used to accomplish this aim. Highly abundant phospholipids and triglycerides (TGs) contributed to the interindividual variability in phylloquinone, α-tocopherol, and γ-tocopherol. Interindividual variability in lycopene concentrations was driven by concentrations of low-abundant TG. 25-Hydroxyvitamin D3, retinol, and the other carotenoids were not influenced by lipids. Except for lycopene, evaluation of lipids beyond class does not appear to further explain the interindividual variability in circulating concentrations of fat-soluble vitamins and carotenoids.

Serial Biomarkers of De Novo Lipogenesis Fatty Acids and Incident Heart Failure in Older Adults: The Cardiovascular Health Study

Background De novo lipogenesis (DNL) is an endogenous pathway that converts excess dietary starch, sugar, protein, and alcohol into specific fatty acids (FAs). Although elevated DNL is linked to several metabolic abnormalities, little is known about how long-term habitual levels and changes in levels of FAs in the DNL pathway relate to incident heart failure (HF). Methods and Results We investigated whether habitual levels and changes in serial measures of FAs in the DNL pathway were associated with incident HF among 4249 participants free of HF at baseline. Plasma phospholipid FAs were measured at baseline, 6 years, and 13 years using gas chromatography, and risk factors for HF were measured using standardized methods. Incident HF was centrally adjudicated using medical records. We prospectively evaluated associations with HF risk of (1) habitual FA levels, using cumulative updating to assess long-term exposure, and (2) changes in FA levels over time. During 22.1 years of follow-up, 1304 HF cases occurred. After multivariable adjustment, habitual levels and changes in levels of palmitic acid (16:0) were positively associated with incident HF (interquintile hazard ratio [95% CI]=1.17 [1.00-1.36] and 1.26 [1.03-1.55], respectively). Changes in levels of 7-hexadecenoic acid (16:1n-9) and vaccenic acid (18:1n-7) were each positively associated with risk of HF (1.36 [1.13-1.62], and 1.43 [1.18-1.72], respectively). Habitual levels and changes in levels of myristic acid (14:0), palmitoleic acid (16:1n-7), stearic acid (18:0), and oleic acid (18:1n-9) were not associated with incident HF. Conclusions Both habitual levels and changes in levels of 16:0 were positively associated with incident HF in older adults. Changes in 16:1n-9 and 18:1n-7 were also positively associated with incident HF. These findings support a potential role of DNL or these DNL-related FAs in the development of HF.

Relation of Kidney Function Decline and NT-proBNP With Risk of Mortality and Readmission in Acute Decompensated Heart Failure

BACKGROUND

Acute declines in kidney function occur in approximately 20%-30% of patients with acute decompensated heart failure, but its significance is unclear, and the importance of its context is not known. This study aimed to determine the prognostic value of a decline in kidney function in the context of decongestion among patients admitted with acute decompensated heart failure.

METHODS

Using data from patients enrolled in the Ultrafiltration in Decompensated Heart Failure with Cardiorenal Syndrome Study (CARRESS) and Diuretic Optimization Strategies Evaluation (DOSE) trials, we used multivariable Cox regression models to evaluate the association between decline in estimated glomerular filtration rate (eGFR) and change in N-terminal pro-b-type natriuretic peptide (NT-proBNP) with a composite outcome of death and rehospitalization, as well as testing for an interaction between the two.

RESULTS

Among 435 patients, in-hospital decline in eGFR was not significantly associated with death and rehospitalization (hazard ratio [HR] = 0.89 per 30% decline, 95% confidence interval [CI] 0.74, 1.07), whereas decline in NT-proBNP was associated with lower risk (HR = 0.69 per halving, 95% CI 0.58, 0.83). There was a significant interaction (P = 0.002 unadjusted; P = 0.03 adjusted) between decline in eGFR and change in NT-proBNP where a decline in eGFR was associated with better outcomes when NT-proBNP declined (HR = 0.78 per 30% decline in eGFR, 95% CI 0.61, 0.99), but not when NT-proBNP increased (HR = 0.99, 95% CI 0.76, 1.30).

CONCLUSIONS

Decline in kidney function during therapy for acute decompensated heart failure is associated with improved outcomes as long as NT-proBNP levels are decreasing as well, suggesting that incorporation of congestion biomarkers may aid clinical interpretation of eGFR declines.

The Contribution of Lipids to the Interindividual Response of Vitamin K Biomarkers to Vitamin K Supplementation

SCOPE

A better understanding of factors contributing to interindividual variability in biomarkers of vitamin K can enhance the understanding of the equivocal role of vitamin K in cardiovascular disease. Based on the known biology of phylloquinone, the major form of vitamin K, it is hypothesized that plasma lipids contribute to the variable response of biomarkers of vitamin K metabolism to phylloquinone supplementation.

METHODS AND RESULTS

The association of plasma lipids and 27 lipid-related genetic variants with the response of biomarkers of vitamin K metabolism is examined in a secondary analysis of data from a 3-year phylloquinone supplementation trial in men (n = 66) and women (n = 85). Year 3 plasma triglycerides (TG), but not total cholesterol, LDL-cholesterol, or HDL-cholesterol, are associated with the plasma phylloquinone response (men: β = 1.01, p < 0.001, R2  = 0.34; women: β = 0.61, p = 0.008, R2  = 0.11; sex interaction p = 0.077). Four variants and the TG-weighted genetic risk score are associated with the plasma phylloquinone response in men only. Plasma lipids are not associated with changes in biomarkers of vitamin K function (undercarboxylated osteocalcin and matrix gla protein) in either sex.

CONCLUSION

Plasma TG are an important determinant of the interindividual response of plasma phylloquinone to phylloquinone supplementation, but changes in biomarkers of vitamin K carboxylation are not influenced by lipids.

Change in Cardiometabolic Risk Factors Associated With Magnitude of Weight Regain 3 Years After a 1-Year Intensive Lifestyle Intervention in Type 2 Diabetes Mellitus: The Look AHEAD Trial

Background

Weight regain after weight loss is common. The impact on cardiometabolic risk factors is not well established.

Methods and Results

Publicly available data were analyzed from participants of the Look AHEAD (Action for Health in Diabetes) trial with ≥3% initial weight loss (n=1561) during a 1‐year intensive lifestyle intervention and with year 4 follow‐up data. Participants who regained (regainers) or maintained (maintainers) weight loss were defined with 5 dichotomized cut points (0%, 25%, 50%, 75%, and 100%) of percentage weight loss regained (weight change from years 1–4 as percentage of first year weight loss). Change in cardiometabolic risk factors after initial weight loss was compared in maintainers and regainers, after controlling for demographics, medications, and baseline and year 1 change in body mass index. The effect was assessed separately in participants with <10% and ≥10% initial weight loss, and women and men. Maintainers exhibited significant improvements to the cardiometabolic risk factors assessed compared with regainers. No weight regain cut point maximized risk difference between maintainers and regainers across risk factors or sex/initial weight loss subgroups. For many risk factors, allowing more regain as part of maintenance (increasing cut point) diminished the cardiometabolic benefit among maintainers.

Conclusions

Maintaining weight loss was better than regain for all risk factors. No single cut point maximized the risk difference between maintainers and regainers. Maintainers who kept off ≥75% of weight lost had the greatest benefit. These findings emphasize the importance of intervention programs focusing not only on weight loss but weight loss maintenance, given the adverse consequences of the latter.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00017953.

Knockdown of CD44 expression decreases valve interstitial cell calcification in vitro

The lack of pharmaceutical targets available to treat patients with calcific aortic valve disease (CAVD) necessitates further research into the specific mechanisms of the disease. The significant changes that occur to the aortic valves extracellular matrix (ECM) during the progression of CAVD suggests that these proteins may play an important role in calcification. Exploring the relationship between valve interstitial cells (VICs) and the ECM may lead to a better understand of CAVD mechanisms and potential pharmaceutical targets. In this study, we look at the effect of two ECM components, collagen and hyaluronic acid (HA), on the mineralization of VICs within the context of a two-dimensional, polyacrylamide (PAAM) model system. Using a novel, nondestructive imaging technique, we were able to track calcific nodule development in culture systems over a 3-wk time frame. We saw a significant increase in the size of the nodules grown on HA PAAM gels as compared with collagen PAAM gels, suggesting that HA has a direct effect on mineralization. Directly looking at the two known receptors of HA, CD44 and receptor for HA-mediated motility (RHAMM), and using siRNA knockdown revealed that a decrease in CD44 expression resulted in a reduction of calcification. A decrease in CD44, through siRNA knockdown, reduces mineralization on HA PAAM gels, suggesting a potential new target for CAVD treatment. NEW & NOTEWORTHY Our in vitro model of calcific aortic valve disease shows an interaction between the hyaluronic acid binding protein CD44 with the osteogenic factor OPN as a potential mechanism of aortic valve calcification. Using siRNA knockdown of CD44, we show an upregulation of OPN expression with a decrease in overall mineralization.

Distinct Phenotypes Induced by Three Degrees of Transverse Aortic Constriction in Mice

Transverse aortic constriction (TAC) is a well-established model of pressure overload-induced cardiac hypertrophy and failure in mice. The degree of constriction “tightness” dictates the TAC severity and is determined by the gauge (G) of needle used. Though many reports use the TAC model, few studies have directly compared the range of resulting phenotypes. In this study adult male mice were randomized to receive TAC surgery with varying degrees of tightness: mild (25G), moderate (26G) or severe (27G) for 4 weeks, alongside sham-operated controls. Weekly echocardiography and terminal haemodynamic measurements determined cardiac remodelling and function. All TAC models induced significant, severity-dependent left ventricular hypertrophy and diastolic dysfunction compared to sham mice. Mice subjected to 26G TAC additionally exhibited mild systolic dysfunction and cardiac fibrosis, whereas mice in the 27G TAC group had more severe systolic and diastolic dysfunction, severe cardiac fibrosis, and were more likely to display features of heart failure, such as elevated plasma BNP. We also observed renal atrophy in 27G TAC mice, in the absence of renal structural, functional or gene expression changes. 25G, 26G and 27G TAC produced different responses in terms of cardiac structure and function. These distinct phenotypes may be useful in different preclinical settings.

CXCR3 regulates CD4+ T cell cardiotropism in pressure overload-induced cardiac dysfunction

Heart failure (HF) is associated in humans and mice with increased circulating levels of CXCL9 and CXCL10, chemokine ligands of the CXCR3 receptor, predominantly expressed on CD4+ Th1 cells. Chemokine engagement of receptors is required for T cell integrin activation and recruitment to sites of inflammation. Th1 cells drive adverse cardiac remodeling in pressure overload-induced cardiac dysfunction, and mice lacking the integrin ligand ICAM-1 show defective T cell recruitment to the heart. Here, we show that CXCR3+ T cells infiltrate the heart in humans and mice with pressure overload-induced cardiac dysfunction. Genetic deletion of CXCR3 disrupts CD4+ T cell heart infiltration and prevents adverse cardiac remodeling. We demonstrate that cardiac fibroblasts and cardiac myeloid cells that include resident and infiltrated macrophages are the source of CXCL9 and CXCL10, which mechanistically promote Th1 cell adhesion to ICAM-1 under shear conditions in a CXCR3-dependent manner. To our knowledge, our findings identify a previously unrecognized role for CXCR3 in Th1 cell recruitment into the heart in pressure overload-induced cardiac dysfunction.

Weight gain prevention buffers the impact of CETP rs3764261 on high density lipoprotein cholesterol in young adulthood: The Study of Novel Approaches to Weight Gain Prevention (SNAP)

BACKGROUND AND AIMS

Two weight gain prevention strategies, one targeting small changes to diet and physical activity and a second targeting large changes, significantly reduced weight gain in young adulthood. We examined whether weight gain prevention blunts genetic risk for body weight increase and/or high density lipoprotein cholesterol (HDL-C) lowering over two years.

METHODS AND RESULTS

Participants were 524 male and female young adults (mean age = 28.2, SD = 4.3; mean BMI = 25.5, SD = 2.6). Obesity-related SNPs accounting for ≥ 0.04% of the variance were genotyped and combined into a genetic risk score. For HDL-C, SNPs within CETP, LIPC and FADS2 were genotyped. The obesity-related genetic risk score did not predict change in BMI independently or in interaction with treatment arm. However, consistent with the prior literature, each copy of the HDL-C risk, C, allele at CETP rs3764261 was associated with lower HDL-C at baseline. Moreover, significant interaction between SNP and treatment arm for change in HDL-C was observed (p = 0.02). In the control group, HDL-C change was dependent upon rs3764261 (p = 0.004) with C allele carriers showing a continued reduction in HDL-C. In contrast, within the two intervention groups, HDL-C increased on average with no differential effect of rs3764261 (p > 0.24). Notably, even among carriers of the CC genotype, small and large change arms were associated with increased HDL-C and the control arm a reduction (p = 0.013).

CONCLUSIONS

The C allele at CETP rs3764261 is a strong risk factor for low HDL-C in young adulthood but weight gain prevention may mitigate this risk. CLINICAL TRIAL REGISTRY NUMBER AND WEBSITE: clinicaltrials.gov Identifier: NCT01183689, https://clinicaltrials.gov/.

Transcriptome analysis of pig intestinal cell monolayers infected with Cryptosporidium parvum asexual stages

Background

Human cryptosporidiosis is caused primarily by two species of apicomplexan protozoa, Cryptosporidium parvum and C. hominis. In cultured cell monolayers, the parasite undergoes two generations of asexual multiplication (merogony). However, the proportion of parasites completing the life-cycle is low and insufficient to sustain continuous propagation. Due to the intracellular location of meronts and later life-cycle stages, oocyst and sporozoites are the only forms of the parasite that can readily be isolated.

Results

Research on the replicating forms of Cryptosporidium parasites and their interaction with the host cell remains challenging. Based on an RNA-Seq analysis of monolayers of pig epithelial cells infected with C. parvum, here we report on the impact of merogony on the host’s gene regulation. Analysis of the transcriptome of infected and uninfected monolayers demonstrates a significant impact of the infection on host cell gene expression. A total of 813 genes were differentially expressed. Functional terms significantly altered in response to infection include phosphoprotein, RNA binding and acetylation. Upregulation of cell cycle pathways indicates an increase in mitosis. Notably absent from differentially enriched functional categories are stress- and apoptosis-related functions. The comparison of the combined host-parasite transcriptome reveals that C. parvum gene expression is less diverse than the host cell transcriptome and is highly enriched for genes encoding ribosomal functions, such as ribosomal proteins.

Conclusions

These results indicate that C. parvum infection significantly changes host biological functions and provide new insight into gene functions driving early C. parvum intracellular development.

Electronic supplementary material

The online version of this article (10.1186/s13071-018-2754-3) contains supplementary material, which is available to authorized users.

Comparison among criteria to define successful weight-loss maintainers and regainers in the Action for Health in Diabetes (Look AHEAD) and Diabetes Prevention Program trials

Background: Given the low rates of successful weight maintenance after lifestyle-induced weight loss, it is critical to develop approaches that distinguish successful weight-loss maintainers from regainers.Objective: The aim of this study was to compare published categorization criteria that differentiate maintainers and regainers via quantitative agreement.Design: The study used publicly available data from Look AHEAD (Action for Health in Diabetes; n = 1791) and Diabetes Prevention Program (DPP; n = 613) participants with ≥3% initial weight loss after lifestyle interventions and 4-y follow-up data. Eight previously published criteria defining maintainers and regainers were compared with respect to number of participants and concordance via agreement statistics. Criteria were assessed separately among those with 3-9% and ≥10% initial weight loss.Results: Regainers had higher body weight at year 4 than did maintainers (mean difference range: 6.6-11.9 kg in Look AHEAD; 11.5-14.6 kg in DPP; P < 0.0001). Assessing concordance among criteria, agreement was dependent on initial weight loss. Among those with 3-9% initial weight loss in both cohorts, 9 of 28 comparisons were concordant (agreement ≥80%). Among those with ≥10% initial weight loss, 7 of 28 comparisons in Look AHEAD and 13 of 28 in the DPP were in high agreement. The definition of successful weight-loss maintenance "regaining ≤25% of initial weight loss during maintenance" showed high agreement with the most commonly used definition of "staying ≥10% below initial weight" among those with ≥10% initial weight loss (agreement: 85.0% in Look AHEAD; 87.4% in DPP). The same definition of ≤25% regain showed high agreement with the definition of staying ≥5% below initial weight among those with 3-9% initial weight loss (agreement: 91.6% in Look AHEAD; 90.5% in DPP).Conclusions: Although all of the criteria discriminated on the basis of weight loss, many showed low agreement, which limited cross-study comparisons. Among criteria with high agreement, the definition of successful weight maintenance "regaining ≤25% of initial weight loss during maintenance" is a preferred definition of success, given the realistic challenges of maintaining 100% weight loss and flexible application in populations with high initial weight-loss variations. This trial was registered at clinicaltrials.gov as NCT00017953 (Look AHEAD) and NCT00004992 (DPP).

Feline Hypertrophic Cardiomyopathy: A Spontaneous Large Animal Model of Human HCM

Hypertrophic cardiomyopathy (HCM) is a common disease in pet cats, affecting 10-15% of the pet cat population. The similarity to human HCM, the rapid progression of disease, and the defined and readily determined endpoints of feline HCM make it an excellent natural model that is genotypically and phenotypically similar to human HCM. The Maine Coon and Ragdoll cats are particularly valuable models of HCM because of myosin binding protein-C mutations and even higher disease incidence compared to the overall feline population. The cat overcomes many of the limitations of rodent HCM models, and can provide enhanced translation of information from in vitro and induced small animal models to human clinical trials. Physicians and veterinarians working together in a collaborative and interdisciplinary approach can accelerate the discovery of more effective treatments for this and other cardiovascular diseases affecting human and veterinary patients.

Multistate Model to Predict Heart Failure Hospitalizations and All-Cause Mortality in Outpatients With Heart Failure With Reduced Ejection Fraction: Model Derivation and External Validation

BACKGROUND

Outpatients with heart failure (HF) who are at high risk for HF hospitalization and death may benefit from early identification. We sought to develop and externally validate a model to predict both HF hospitalization and mortality that accounts for the semicompeting nature of the 2 outcomes and captures the risk associated with the transition from the stable outpatient state to the post-HF hospitalization state.

METHODS AND RESULTS

A multistate model to predict HF hospitalization and all-cause mortality was derived using data (n=3834) from the HEAAL study (Heart Failure Endpoint evaluation of Angiotensin II Antagonist Losartan), a multinational randomized trial in symptomatic patients with reduced left ventricular ejection fraction. Twelve easily and reliably obtainable demographic and clinical predictors were prespecified for model inclusion. Model performance was assessed in the SCD-HeFT cohort (Sudden Cardiac Death in Heart Failure Trial; n=2521). At 1 year, the probability of being alive without HF hospitalization was 94% for a typical patient in the lowest risk quintile and 77% for a typical patient in the highest risk quintile and this variability in risk continued through 7 years of follow-up. The model c-index was 0.72 in the derivation cohort, 0.66 in the validation cohort, and 0.69 in the implantable cardiac defibrillator arm of the validation cohort. There was excellent calibration across quintiles of predicted risk.

CONCLUSIONS

Our findings illustrate the advantages of a multistate modeling approach, providing estimates of HF hospitalization and death in the same model, comparison of predictors for the different outcomes and demonstrating the different trajectories of patients based on baseline characteristics and intermediary events.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00000609 and NCT00090259.

Genetic modifiers of cardiorespiratory fitness response to lifestyle intervention

PURPOSE

Numerous prospective studies indicate that improved cardiorespiratory fitness reduces type 2 diabetes risk and delays disease progression. We hypothesized that genetic variants modify fitness response to an intensive lifestyle intervention (ILI) in the Action for Health in Diabetes (Look AHEAD) randomized clinical trial, aimed to detect whether ILI will reduce cardiovascular events in overweight/obese subjects with type 2 diabetes compared with a standard of care.

METHODS

Polymorphisms in established fitness genes and in all loci assayed on the Illumina CARe iSelect chip were examined as predictors of change in MET level, estimated using a treadmill test, in response to a 1-yr intervention in 3899 participants.

RESULTS

We identified a significant signal in previously reported fitness-related gene RUNX1 that was associated with 1-yr METs response in ILI (0.19 ± 0.04 MET less improvement per minor allele copy; P = 1.9 × 10(-5)) and genotype-intervention interaction (P = 4.8 × 10(-3)). In the chipwide analysis, FKBP7 rs17225700 showed a significant association with ILI response among subjects not receiving beta-blocker medications (0.47 ± 0.09 METs less improvement; P = 5.3 × 10(-5)) and genotype-treatment interaction (P = 5.3 × 10(-7)). The Gene Relationships Among Implicated Loci pathway-based analysis identified connections between associated genes, including those influencing vascular tone, muscle contraction, cardiac energy substrate dynamics, and muscle protein synthesis.

CONCLUSIONS

This is the first study to identify genetic variants associated with fitness responses to a randomized lifestyle intervention in overweight/obese diabetic individuals. RUNX1 and FKBP7, involved in erythropoesis and muscle protein synthesis, respectively, are related to change in cardiorespiratory fitness in response to exercise.

Cardiac Myosin Binding Protein-C Autoantibodies are Potential Early Indicators of Cardiac Dysfunction and Patient Outcome in Acute Coronary Syndrome

•

ACS remains a leading cause of death worldwide.

•

cMyBP-C-AAbs were detected in ACS patients' sera upon arrival to the emergency department.

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The presence of cMyBP-C-AAbs was negatively associated with cardiovascular function and positively associated with the degree of myocardial injury as determined by circulating levels of serum proteins in ACS patients.

•

The development of novel indicators to predict infarction severity and cardiovascular function following ischemic injury may provide early treatment recommendations for ACS patients to limit myocardial damage.

The degradation and release of cardiac myosin binding protein-C (cMyBP-C) upon cardiac damage may stimulate an inflammatory response and autoantibody (AAb) production. We determined whether the presence of cMyBP-C-AAbs associated with adverse cardiac function in cardiovascular disease patients. Importantly, cMyBP-C-AAbs were significantly detected in acute coronary syndrome patient sera upon arrival to the emergency department, particularly in ST-segment elevation myocardial infarction patients. Patients positive for cMyBP-C-AAbs had reduced left ventricular ejection fraction and elevated levels of clinical biomarkers of myocardial infarction. We conclude that cMyBP-C-AAbs may serve as early predictive indicators of deteriorating cardiac function and patient outcome in acute coronary syndrome patients prior to the infarction.

Perinatal Natural History of the Ts1Cje Mouse Model of Down Syndrome: Growth Restriction, Early Mortality, Heart Defects, and Delayed Development

Background

The Ts1Cje model of Down syndrome is of particular interest for perinatal studies because affected males are fertile. This permits affected pups to be carried in wild-type females, which is similar to human pregnancies. Here we describe the early natural history and growth profiles of Ts1Cje embryos and neonates and determine if heart defects are present in this strain.

Methods

Pups were studied either on embryonic (E) day 15.5, or from postnatal (P) day 3 through weaning on P21. PCR amplification targeting the neomycin cassette (present in Ts1Cje) and Sry (present in males) was used to analyze pup genotypes and sex ratios. Body weights and lengths, as well as developmental milestones, were recorded in Ts1Cje mice and compared to their wild-type (WT) littermates. Histological evaluations were performed at E15.5 to investigate the presence or absence of heart defects. Pups were divided into two groups: Ts1Cje-I pups survived past weaning and Ts1Cje-II pups died at some point before P21.

Results

Ts1Cje mouse embryos showed expected Mendelian ratios (45.8%, n = 66 for Ts1Cje embryos; 54.2%, n = 78 for WT embryos). Histological analysis revealed the presence of ventricular septal defects (VSDs) in 21% of Ts1Cje E15.5 embryos. After weaning, only 28.2% of pups were Ts1Cje (185 Ts1Cje out of 656 total pups generated), with males predominating (male:female ratio of 1.4:1). Among the recovered dead pups (n = 207), Ts1Cje (63.3%, n = 131, p<0.01) genotype was found significantly more often than WT (36.7%, n = 76). Retrospective analysis of Ts1Cje-II (pre-weaning deceased) pups showed that they were growth restricted compared to Ts1Cje-I pups (post-weaning survivors). Growth restriction correlated with statistically significant delays in achieving several neonatal milestones between P3 and P21 compared to Ts1Cje-I (post-weaning survivors) neonates and WT littermates.

Conclusions

Ts1Cje genotype is not associated with increased early in utero mortality. Cardiac defects, specifically VSDs, are part of the phenotype in this strain. There is increased neonatal mortality in Ts1Cje pups, with sex differences observed. Ts1Cje mice that died in the neonatal period were more likely to be growth restricted and delayed in achieving neonatal developmental milestones.

In-hospital measurement of left ventricular ejection fraction and one-year outcomes in acute coronary syndromes: results from the IMMEDIATE Trial

BACKGROUND

In patients with acute coronary syndrome (ACS), reduced left ventricular ejection fraction (LVEF) is a known marker for increased mortality. However, the relationship between LVEF measured during index ACS hospitalization and mortality and heart failure (HF) within 1 year are less well-defined.

METHODS

We performed a retrospective analysis of 445 participants in the IMMEDIATE Trial who had LVEF measured by left ventriculography or echocardiogram during hospitalization.

RESULTS

Adjusting for age and coronary artery disease (CAD) history, lower LVEF was significantly associated with 1-year mortality or hospitalization for HF. For every 5 % LVEF reduction, the hazard ratio [HR] was 1.26 (95 % CI 1.15, 1.38, P < 0.001). Participants with LVEF < 40 % had higher hazard of 1-year mortality or HF hospitalization than those with LVEF > 40 (HR 3.59; 95 % CI 2.05, 6.27, P < 0.001). The HRs for the association of LVEF with the study outcomes were similar whether measured by left ventriculography or by echocardiography, (respectively, HR 1.32; 95 % CI 1.15, 1.51 and 1.21; 95 % CI 1.106, 1.35, interaction P = 0.32) and whether done within 24 h or not within 24 h (respectively, HR 1.28; 95 % CI 1.10, 1.50 and 1.23; 95 % CI 1.10, 1.38, interaction P = 0.67).

CONCLUSIONS

Among patients with ACS, lower in-hospital LVEF is associated with increased 1-year mortality or hospitalization for HF, regardless of the method or timing of the LVEF assessment. This has prognostic implications for clinical practice and suggests the possibility of using various methods of LVEF determination in clinical research.

C-Reactive protein reactions to glucose-insulin-potassium infusion and relations to infarct size in patients with acute coronary syndromes

Background

Some benefits of glucose-insulin-potassium (GIK) in patients with acute coronary syndromes (ACS) may be from an anti-inflammatory effect. The primary aim of this study was to assess the impact of GIK administration early in the course of ACS on inflammatory marker C-reactive protein (CRP) levels. A secondary aim was to investigate the association between CRP and 30-day infarct size.

Methods and Results

Retrospective analysis of participants with ACS randomly assigned to GIK or placebo for at least 8 h in the IMMEDIATE Trial biological mechanism cohort (n = 143). High sensitivity CRP (hs-CRP) was measured at emergency department presentation, and 6 and 12 h into infusion. Logarithmically transformed hs-CRP values at 12-hours were lower with GIK vs. placebo (mean =0.65 mg/L in GIK, 0.84 mg/L in placebo), with a marginal trend toward significance (P = 0.053). Furthermore, using mixed models of hs-CRP, time, and study group, there was a significant increase in hs-CRP levels over time, but the rate of change did not differ between treatment arms (P = 0.3). Multivariable analysis showed that an elevation in hs-CRP, measured at 12 h, was an independent predictor of 30-day infarct size (β coefficient, 6.80; P = 0.04) using sestamibi SPECT imaging.

Conclusions

The results of this study show no significant effect of GIK on hs-CRP. In addition our results show that in patients with ACS, hs-CRP measured as early as 12 h can predict 30-day infarct size.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-015-0153-7) contains supplementary material, which is available to authorized users.

Genetic Predisposition to Weight Loss and Regain With Lifestyle Intervention: Analyses From the Diabetes Prevention Program and the Look AHEAD Randomized Controlled Trials

Clinically relevant weight loss is achievable through lifestyle modification, but unintentional weight regain is common. We investigated whether recently discovered genetic variants affect weight loss and/or weight regain during behavioral intervention. Participants at high-risk of type 2 diabetes (Diabetes Prevention Program [DPP]; N = 917/907 intervention/comparison) or with type 2 diabetes (Look AHEAD [Action for Health in Diabetes]; N = 2,014/1,892 intervention/comparison) were from two parallel arm (lifestyle vs. comparison) randomized controlled trials. The associations of 91 established obesity-predisposing loci with weight loss across 4 years and with weight regain across years 2-4 after a minimum of 3% weight loss were tested. Each copy of the minor G allele of MTIF3 rs1885988 was consistently associated with greater weight loss following lifestyle intervention over 4 years across the DPP and Look AHEAD. No such effect was observed across comparison arms, leading to a nominally significant single nucleotide polymorphism×treatment interaction (P = 4.3 × 10(-3)). However, this effect was not significant at a study-wise significance level (Bonferroni threshold P < 5.8 × 10(-4)). Most obesity-predisposing gene variants were not associated with weight loss or regain within the DPP and Look AHEAD trials, directly or via interactions with lifestyle.

Lifestyle Intervention for Weight Loss and Cardiometabolic Changes in the Setting of Glucokinase Regulatory Protein Inhibition: Glucokinase Regulatory Protein-Leu446Pro Variant in Look AHEAD

BACKGROUND

Glucokinase regulatory protein (GCKR) inhibitors offer a novel treatment approach for glucose control in diabetes mellitus; however, their cardiometabolic effects, particularly in relation to increased triglycerides and C-reactive protein (CRP) levels, are of concern. GCKR Leu446Pro is a common variant associated with reduced GCKR function, increased triglycerides, and CRP.

METHODS AND RESULTS

We investigated whether a 1-year intensive lifestyle intervention (ILI) for weight loss would avert the unfavorable cardiometabolic effects associated with GCKR Leu446Pro when compared with a diabetes mellitus support and education arm in overweight/obese individuals with type 2 diabetes mellitus with triglyceride (n=3214) and CRP (n=1411) data participating in a randomized lifestyle intervention study for weight loss, Action for Health in Diabetes Mellitus (Look AHEAD). Once demographics, medication use and baseline adiposity, and fitness were accounted for, ILI did not modify the baseline association of GCKR-Leu446Pro with elevated triglycerides (β±SE=0.067±0.013, P=1.5×10(-7) and β±SE=0.052±0.015, P=5×10(-4)) or with elevated CRP (β±SE=0.136±0.034, P=5.1×10(-5)and β±SE=0.903±0.038, P=0.015) in the overall sample and Non-Hispanic Whites, respectively. The lack of a protective effect from ILI at 1 year when compared with diabetes mellitus support and education (ILI versus diabetes mellitus support and education interaction for triglyceride and CRP change, respectively: P=0.64 and 0.37 in the overall sample; P=0.27 and 0.05 in Non-Hispanic Whites) persisted after additional adjustment for changes in adiposity and fitness.

CONCLUSIONS

Moderate improvements in adiposity and fitness with ILI did not mitigate the adverse cardiometabolic effects of GCKR inhibition in overweight/obese individuals with diabetes mellitus.

Serum adiponectin levels in patients with acute coronary syndromes: Serial changes and relation to infarct size

BACKGROUND

The role of adiponectin in patients with acute coronary syndromes is incompletely defined. This study investigated adiponectin levels in patients with acute coronary syndromes and the association between adiponectin and 30-day infarct size and 1-year clinical outcomes.

METHODS

Retrospective analysis of 120 participants with acute coronary syndromes enrolled in the Immediate Myocardial Metabolic Enhancement During Initial Assessment and Treatment in Emergency care Trial. Blood levels were tested three times within 24 h of onset of ischaemic symptoms. Infarct size was measured at 30 days. The 1-year clinical outcome was the composite of all-cause mortality or hospitalization for heart failure.

RESULTS

Using linear mixed models, log adiponectin levels decreased by -0.005 µg/mL per hour (p = 0.035). After stratifying the analysis by gender, there was no decrease in log adiponectin in men; however, levels decreased by -0.01 µg/mL per hour in women (p = 0.02). Results of multivariable regression models showed no association between log adiponectin and infarct size (β = -1.1, p = 0.64). Log adiponectin levels did not predict 1-year outcomes using Cox-proportional hazard models.

CONCLUSION

There was a small decrease in plasma adiponectin shortly after symptoms of ischaemia, more noticeable in women. No relationship was found between adiponectin and infarct size or clinical outcomes. This adds to evidence showing no clear association between adiponectin and adverse outcomes in patients with acute coronary syndromes.

Pharmacogenomics of estrogens on changes in carotid artery intima-medial thickness and coronary arterial calcification: Kronos Early Estrogen Prevention Study

Prior to the initiation of menopausal hormone treatment (MHT), genetic variations in the innate immunity pathway were found to be associated with carotid artery intima-medial thickness (CIMT) and coronary arterial calcification (CAC) in women (n = 606) enrolled in the Kronos Early Estrogen Prevention Study (KEEPS). Whether MHT might affect these associations is unknown. The association of treatment outcomes with variation in the same 764 candidate genes was evaluated in the same KEEPS participants 4 yr after randomization to either oral conjugated equine estrogens (0.45 mg/day), transdermal 17β-estradiol (50 μg/day), each with progesterone (200 mg/day) for 12 days each month, or placebo pills and patch. Twenty SNPs within the innate immunity pathway most related with CIMT after 4 yr were not among those associated with CIMT prior to MHT. In 403 women who completed the study in their assigned treatment group, single nucleotide polymorphisms (SNPs) within the innate immunity pathway were found to alter the treatment effect on 4 yr change in CIMT (i.e., significant interaction between treatment and genetic variation in the innate immunity pathway; P < 0.001). No SNPs by treatment effects were observed with changes of CAC >5 Agatston units after 4 yr. Results of this study suggest that hormonal status may interact with genetic variants to influence cardiovascular phenotypes, specifically, the pharmacogenomic effects within the innate immunity pathway for CIMT.