Citations

Abstract Background Previous studies suggest that autoantibodies against cardiac myosin lead to dilated cardiomyopathy (DCM). Anti-cardiac myosin antibodies cross-react with the beta adrenergic receptor (βAR) and signal cAMP-dependent protein kinase A (PKA) in cardiomyocytes leading to apoptosis, fibrosis, dilated cardiomyopathy and arrhythmias. Purpose To determine if cross-reactive anti-cardiac myosin/anti-βAR autoantibodies which signal cardiomyocytes through PKA might play a role to establish DCM by promoting remodeling, apoptosis, and fibrosis. Methods Forty-one adults with DCM were enrolled <6 months from symptom onset and followed for 12 months. Serum and myocarditis/DCM-derived human mAb were analyzed by ELISA for autoantibodies, and a PKA assay measured anti-HCM/βAR antibody-mediated signaling of cardiomyocytes (ATCC primary heart cell line H9c2). The top 50 genes differentially expressed in the cardiomyocytes treated with sera or human mAb were identified and compared to genes differentially expressed in blood of DCM patients to identify shared disease-specific genes. Results Anti-HCM autoantibodies including autoantibody responses against 32 overlapping synthetic peptides of the S2 fragment of HCM were significantly elevated in patients whose ejection fraction did not improve over 1-year compared to those with improved ejection fraction. The human mAb confirmed our results with HCM, βAR, specific HCM peptides, and PKA signaling. RNA sequencing revealed differentially expressed genes in serum/mAb-treated cardiomyocytes compared to genes identified after RNA sequencing of peripheral blood of patients (n=10) with DCM for >1 year from onset. A primary heart cell line (H9c2-ATCC) treated with myocarditis/DCM patient sera or human mAb revealed differentially expressed genes associated with cardiac hypertrophy and heart failure, and included inflammasome component NLRP3 and complement factor H. Ingenuity Pathway Analyses revealed 27, 7, and 1 differentially expressed genes related to apoptosis, fibrosis, and hypoxia, respectively. Gene expression of CASZ1, a transcription factor important in protection against DCM, was strongly correlated with PKA signaling (r=0.89). The KDM6B gene for lysine demethylase associated with hypoxia and apoptosis pathways and was shared between cardiomyocyte and peripheral blood analysis of DCM patients. Overall, 5 genes were shared in heart failure vs in vitro Ab-treated cardiomyocyte RNA sequencing analysis: CYP4F3, KDM6B, MBOAT7, SMAP2, and DDIT4, which affects phosphorylation of mTOR to promote autophagy and cell death, cardiac hypertrophy and dysfunction. Conclusions Significantly higher responses to cardiac myosin in patients with DCM were related to lack of left ventricular function improvement and to differential expression of genes promoting apoptosis, fibrosis and disease severity. These studies identify autoantibody-directed gene signaling as a potential novel therapeutic target in DCM. Acknowledgement/Funding National Heart, Lung, and Blood Institute, Bethesda, MD, USA

Abstract Background Sports activities may promote arrhythmias in the setting of acute myocarditis. International cardiovascular society recommendations to return to sports activities following acute myocarditis are based on expert consensus in the absence of prospective studies. Purpose We sought to identify patients who may safely resume sports activities 3 months after acute myocarditis. Methods We prospectively enrolled 27 patients with newly diagnosed myocarditis based on clinical parameters, elevated high sensitive troponin (TnT-hs) and cardiac magnetic resonance imaging (CMR) with mildly reduced or preserved LVEF. Follow-up examination included laboratory findings, electrocardiogram (ECG), 48-hour-Holter ECG, echocardiography, exercise stress testing and CMR. Cessation of physical activity was recommended for 3 months. All patients were followed for cardiac events for 12 months. Results Average age was 35 (19–80) years with 73% male patients. All patients performed 3- and 6-month follow-up with above mentioned diagnostic tests. Eight patients did not present for 12-month follow-up, but were contacted by phone. No cardiac events occurred within the interval of 12 months. After 3 months, participants achieved an average of 92% of predicted maximum power on stress test. One case of non-sustained ventricular tachycardia was recorded during 48-hour-Holter ECG. Except for this case, all patients were allowed to resume physical exercise after 3 months. At 6- (n=26) and 12-month (n=19) follow-up no arrhythmias, recurrent myocarditis, worsening left ventricular ejection fraction (LVEF) or physical performance were recorded. TnT-hs, creatine kinase (CK), myoglobin (Mb), and C-reactive protein (CRP) normalized. Conclusion The risk of cardiac events and decreasing LVEF appears to be low after early resumption of exercise in asymptomatic patients who recover from acute myocarditis. Acknowledgement/Funding Forschungskredit of the University of Zurich,the Holcim Foundation, the Hartmann Müller Foundation, and the Walter and Gertrud Siegenthaler Foundation

Abstract Background Cardiomyopathy may occur due to viral infections or drug induced heart damage. Cardiac myosin released from damaged heart has been shown to be a damage associated molecular pattern which binds to TLR2 or TLR8 and can act as an adjuvant to induce a strong autoimmune response against the heart. The result is autoimmunity against the heart which can lead to apoptosis, fibrosis and heart failure. Purpose Immune biomarkers of the early stages of heart failure are needed to identify individuals who develop progressive heart failure, do not recover their ejection fraction and may be candidates for immunotherapies. Methods Forty-one patients with myocarditis and heart failure <6 months after onset were followed for 12 months and compared to age matched controls. Peripheral blood mononuclear cells were analyzed by FACS analysis and serum analyzed by ELISA for autoantibodies and cytokines. Statistical analysis was determined by Mann Whitney test. Peripheral blood of 10 patients with dilated cardiomyopathy (DCM) vs 19 healthy controls were analyzed for gene expression by RNA sequencing and pathway analysis using Reactome. Results Autoantibodies against human cardiac myosin and the beta-adrenergic receptor were significantly elevated in our cohort and functionally acted on cardiomyocytes to activate protein kinase A. Concomitantly, a Th17+ immunophenotype was significantly elevated in blood as well as in cardiac biopsies. CD4+IL17+ T cells (p=0.0008) and Th17-promoting cytokines TGF beta (p<0.0001), IL-6 (p<0.0001), IL-23 (p=0.0001), GMCSF (p=0.0336) and GMCSF-secreting CD4+ T cells (p=0.0006) were significantly elevated in blood. A Th17 immunophenotype was significantly associated with heart failure primarily in males (p=0.029). Persistent heart failure (NYHA class III and IV) and non-recovery of left ventricular function were associated with significantly higher percentages of IL17A-producing T cells at baseline, 6 and 12 months after onset, and IL-17A (p=0.019) and elevated Th17-promoting cytokines IL-6 (p=0.0001) and TGF-beta (p=0.0076). Decreased T regulatory immunosuppressive cells were significantly (p=0.0006) decreased and correlated with elevated Th17 cytokines in heart failure. Overrepresentation analysis of differentially expressed genes (adj p<0.05) in blood of patients with DCM >1year were identified using Reactome which revealed significant (FDR = 1.52E-13) enrichment of neutrophil degranulation (48 genes). Conclusion Our study illustrates a strong Th17 signature in more severe heart failure early in disease with elevated anti-cardiac myosin autoantibodies in non-recovery of left ventricular function. We observed a strong correlation with Th17-related neutrophil degranulation pathways in later disease, which may be biomarkers of fibrosis progression and disease severity in patients with heart failure. Cardiomyopathy with a Th17 signature might be treated with preventive immunomodulatory therapies such as anti-IL17A. Acknowledgement/Funding National Heart Lung and Blood Institute, Bethesda, MD, USA

Abstract Background: Sarcoidosis is a systemic granulomatous disease that may affect the myocardium. This study evaluated the diagnostic and prognostic value of 2-dimensional speckle tracking echocardiography in cardiac sarcoidosis (CS). Methods: Eighty-three patients with extracardiac, biopsy-proven sarcoidosis and definite/probable diagnosis of cardiac involvement diagnosed from January 2005 through December 2016 were included. In order to analyze the alteration of strain parameters in early stages of CS, a subgroup of 23 CS patients with left ventricular ejection fraction (LVEF) within normal limits (LVEF>52% for men: >54% for women, mean value: 57.3%±3.8%) and no wall motion abnormalities was compared with 97 controls (1:4) without cardiac disease. LV and right ventricular (RV) global longitudinal (GLS), circumferential (GCS), and radial (GRS) strain and strain rate (SR) analyses were performed with TomTec software and correlated with cardiac outcomes (including heart failure and arrhythmias). This study was approved by the Mayo Clinic Institutional Review Board, and all patients gave informed written consent to participate. Results: Mean age of CS patients was 53.6±10.8 years, and 34.9% were women. Mean LVEF was 43.2%±12.4%; LV GLS, -12.4%±3.7%; LV GCS, -17.1%±6.5%; LV GRS, 29.3%±12.8%; and RV wall GLS, 14.6%±6.3%. In the 23 patients with early stage CS with normal LVEF and RV systolic function, strain parameters were significantly reduced when compared with controls (respectively: LV GLS, -15.9%±2.5% vs -18.2%±2.7% [ P =.001]; RV GLS, -16.9%±4.5% vs -24.1%±4.0% [ P <.001]). A LV GLS value of -16.3% provided 82.2% sensitivity and 81.2% specificity for the diagnosis of CS (AUC 0.91), while a RV value of -19.9% provided 88.1% sensitivity and 86.7% specificity (AUC 0.93). Hospital admission and heart failure significantly correlated to impaired LV GLS (> -14%). Conclusion: Reduced strain values in the LV GLS and RV GLS can be used in the diagnostic algorithm in patients with suspicion of cardiac sarcoidosis. These values also correlate with adverse cardiovascular events.

Myocarditis is generally a mild and self-limited consequence of systemic infection of cardiotropic viruses. However, patients can develop a temporary or permanent impairment of cardiac function including acute cardiomyopathy with hemodynamic compromise or severe arrhythmias. In this setting, specific causes of inflammation are associated with variable risks of death and transplantation. Recent translational studies suggest that treatments tailored to specific causes of myocarditis may impact clinical outcomes when added to guideline-directed medical care. This review summarizes recent advances in translational research that influence the utility of endomyocardial biopsy for the management of inflammatory cardiomyopathies. Emerging therapies for myocarditis based on these mechanistic hypotheses are entering clinical trials and may add to the benefits of established heart failure treatment.

An estimated 1 billion people worldwide have deficient or insufficient levels of vitamin D (VitD). Considerable evidence indicates that VitD deficiency is associated with an increased risk of autoimmune and cardiovascular disease (CVD), yet it remains unclear whether low VitD is simply a biomarker or has a true pathologic role. In this study we examined how sex differences in VitD influences various CVDs. We found that patients with CVD had significantly lower VitD than healthy controls (no ICD9/10 codes). In myocarditis patients low VitD correlated to poor ejection fraction (EF) in women with myocarditis (p=0.02), but high VitD correlated with low EF in men (p=0.04). In VDR knockout mice we found that VDR decreased myocarditis in females (p=2E-8) but increased inflammation in males (p=0.03) with an increase in total immune cells (p=0.02), CD3, CD4 and CD8 T cells (p=0.04), and the inflammasome in females. VDR altered Treg (p=0.04), mast cells (p=0.04) and cytokine profiles in males. Additionally, sera VitD levels were significantly higher in WT male mice with myocarditis compared to females. Our findings in VDR mice indicate that VitD/VDR reduces myocarditis in females, but increases disease in males. These data suggest that VitD sufficiency may increase inflammation in men, while VitD deficiency may make disease worse in women. These findings suggest that Vitamin D may have a role in the pathogenesis of inflammatory and cardiovascular disease.

Background Myocarditis is an important cause of acute and chronic heart failure. Men with myocarditis have worse recovery and an increased need for transplantation compared with women, but the reason for the sex difference remains unclear. Elevated sera soluble (s) ST 2 predicts mortality from acute and chronic heart failure, but has not been studied in myocarditis patients. Methods and Results Adults with a diagnosis of clinically suspected myocarditis (n=303, 78% male) were identified according to the 2013 European Society of Cardiology position statement. Sera sST 2 levels were examined by ELISA in humans and mice and correlated with heart function according to sex and age. Sera sST 2 levels were higher in healthy men ( P =8×10 −6 ) and men with myocarditis ( P =0.004) compared with women. sST 2 levels were elevated in patients with myocarditis and New York Heart Association class III ‐ IV heart failure ( P =0.002), predominantly in men ( P =0.0003). Sera sST 2 levels were associated with New York Heart Association class in men with myocarditis who were ≤50 years old ( r =0.231, P =0.0006), but not in women ( r =0.172, P =0.57). Sera sST 2 levels were also significantly higher in male mice with myocarditis ( P =0.005) where levels were associated with cardiac inflammation. Gonadectomy with hormone replacement showed that testosterone ( P <0.001), but not estradiol ( P =0.32), increased sera sST 2 levels in male mice with myocarditis. Conclusions We show in a well‐characterized subset of heart failure patients with clinically suspected and biopsy‐confirmed myocarditis that elevated sera sST 2 is associated with an increased risk of heart failure based on New York Heart Association class in men ≤50 years old.

Abstract Aims Cardiac sarcoidosis (CS) often presents with ventricular arrhythmias, heart block, and cardiomyopathy. The prognosis of CS with contemporary management is uncertain. We estimated the impact of baseline and treatment variables on left ventricular ejection fraction (LVEF), ventricular assist device placement, heart transplant, and death. Methods and results We identified patients with CS seen from 1994–2014 at two large academic medical centres. All met the 2014 Heart Rhythm Society expert consensus criteria for diagnosis. From the 574 patients identified, 91 met inclusion criteria. Twenty-two (24.2%) were diagnosed by endomyocardial biopsy. Cardiomyopathy was the primary presentation in 47 patients (51.6%). Within 90 days of diagnosis, 41 patients (45.0%) received prednisone alone, 29 (31.9%) received alternative immunosuppression with or without prednisone, and 21 (23.1%) received no immunosuppression. During follow-up, 31 of 47 cardiomyopathy patients experienced improvement in LVEF, while 23 experienced decline in LVEF or clinical exacerbation, and 15 of 22 patients presenting with ventricular arrhythmia had recurrence. These results did not differ by treatment group. During a median follow-up of 44 months for our cohort, 14 patients reached the composite endpoint of ventricular assist device placement, heart transplant, or death. Survival without the composite outcome did not differ by treatment group, but was worse among patients presenting with cardiomyopathy (log-rank = 0.005). Conclusion In a large series of CS subjects, rates of ventricular arrhythmia and heart failure events remain high with no treatment regimen clearly associated with better outcome. Patients with cardiomyopathy at diagnosis were more likely to reach the composite endpoint.

Objective To examine the association between maternal obesity on left ventricular (LV) size and recovery in women with peripartum cardiomyopathy (PPCM). Study Design This was a prospective analysis of 100 women enrolled within 13 weeks of PPCM diagnosis and followed for a year in the Investigation of Pregnancy Associated Cardiomyopathy study. Adiposity was defined by standard body mass index (BMI) definitions for under/normal weight, overweight, and obesity. Demographic, clinical, and biomarker variables were compared across weight categories. Outcomes LV end-diastolic diameter (LVEDD) and ejection fraction were measured at entry, 6, and 12 months postpartum. Multivariable regression models examined the relationship between adiposity, LV size, and leptin levels with cardiac recovery at 6 and 12 months postpartum. Results Obese and nonobese women had similar LV dysfunction at entry. Obese women had greater LV size and less LV recovery at 6 and 12 months postpartum. BMI was positively associated with leptin and ventricular diameter. Greater BMI at entry remained associated with less ventricular recovery at 6 months (p = 0.02) in adjusted race-stratified models. LVEDD at entry predicted lower ejection fraction at 6 months (p < 0.001) and similarly at 12 months. Conclusion Obese women with PPCM had greater cardiac remodeling, higher leptin levels, and diminished cardiac recovery.