[Nationally standardized broad consent in practice: initial experiences, current developments, and critical assessment]

BACKGROUND

The digitalization in the healthcare sector promises a secondary use of patient data in the sense of a learning healthcare system. For this, the Medical Informatics Initiative's (MII) Consent Working Group has created an ethical and legal basis with standardized consent documents. This paper describes the systematically monitored introduction of these documents at the MII sites.

METHODS

The monitoring of the introduction included regular online surveys, an in-depth analysis of the introduction processes at selected sites, and an assessment of the documents in use. In addition, inquiries and feedback from a large number of stakeholders were evaluated.

RESULTS

The online surveys showed that 27 of the 32 sites have gradually introduced the consent documents productively, with a current total of 173,289 consents. The analysis of the implementation procedures revealed heterogeneous organizational conditions at the sites. The requirements of various stakeholders were met by developing and providing supplementary versions of the consent documents and additional information materials.

DISCUSSION

The introduction of the MII consent documents at the university hospitals creates a uniform legal basis for the secondary use of patient data. However, the comprehensive implementation within the sites remains challenging. Therefore, minimum requirements for patient information and supplementary recommendations for best practice must be developed. The further development of the national legal framework for research will not render the participation and transparency mechanisms developed here obsolete.

From "contraindicated" to "first line" - Current mechanistic insights beyond canonical β-receptor signaling

β-blockers are a solid pillar in the treatment of cardiovascular diseases. However, they are highly discussed regarding effectiveness for certain indications and side-effects. Even though there are up to 20 licensed compounds, only four are used for heart failure (HF) therapy. On the receptor level several key characteristics seem to influence the clinical outcome: subtype selectivity, antagonistic vs (inverse/biased) agonistic properties and -in particular- ancillary capacities. On a molecular level, divergent and novel signaling patterns are being identified and extra-cardiac effects on e.g. inflammation, metabolism and oxidative stress are highlighted. This review discusses different well-known and newly discovered characteristics that need to be considered for HF therapy and in the context of co-morbidities.

Prevalence of anti-beta-1 antibody 6 months after hospitalization for acute heart failure predicts adverse outcome

AIMS

Agonistic antibodies against neurohumoral receptors can induce cardio-noxious effects by altering the baseline receptor activity. To estimate the prevalence of autoantibodies directed against the beta-1 receptor (b1-AAB) in patients admitted to the hospital for acute heart failure (HF) at (i) baseline and (ii) after 6 months of follow-up (F6) and (iii) after another 12 months of follow-up (i.e. 18 months after index hospitalization), to estimate their prognostic impact on clinical outcome (death or first hospitalization for HF).

METHODS AND RESULTS

In 47 patients, b1-AAB were serially determined in serum samples collected at index hospitalization and at 6 months of follow-up (F6) with a flow cytometry-based assay: median age 71 years (quartiles 60, 80), 23 (49%) women, 24 (51%) HF with preserved ejection fraction. Beta1-AAB were detected in three subjects at index hospitalization (6%), and in eight subjects at F6 (17%). There were no differences apparent between patients with and without b1-AAB at F6 with regard to age, sex, type, duration, or main cause of HF. During the 12 month period following F6 (i.e. up to month 18), eight events occurred. Event-free survival was associated with prevalence of b1-AAB at F6. Compared with patients without b1-AAB at F6, age-adjusted Cox regression indicated a higher event risk in patients harbouring b1-AAB, with a hazard ratio of 8.96 (95% confidence interval 1.81-44.50, P = 0.007).

CONCLUSIONS

Our results suggest a possible adverse prognostic relevance of b1-AAB in patients with acute HF, but this observation needs to be confirmed in larger patient collectives.

GBA/GBN-position on the feedback of incidental findings in biobank-based research: consensus-based workflow for hospital-based biobanks

Incidental research findings pose a considerable challenge to hospital-based research biobanks since they are acting as intermediaries between healthcare and research. In a joint action the centralized biobank ibdw (Interdisciplinary Bank of Biomaterials and Data Wuerzburg) together with local authorities drafted a coherent concept to manage incidental research findings in full compliance with relevant ethical and data privacy regulations. The concept was developed and elaborated in close collaboration with the German Biobank Alliance (GBA). Comprehensive documentation of all steps guarantees the traceability of the process. By a mandatory assessment of the findings prior to re-identification of the individual concerned, unnecessary measures can be avoided. The individual's "right not to know" is respected according to the stipulations of the informed consent. As a general principle any communication with the individual occurs exclusively through the hospital and by competent physicians with appropriate knowledge and communication skills. We propose this scheme as a blueprint for reporting workflows for incidental research findings at hospital-based biobanks.

Features of metabolic syndrome and inflammation independently affect left ventricular function early after first myocardial infarction

BACKGROUND

A high body mass index (BMI) is often associated with metabolic syndrome, which is accompanied by systemic low-grade chronic inflammation. Here, we analyzed whether BMI, other components of metabolic syndrome, and/or inflammatory markers correlate with left ventricular geometry, function, and infarct size as assessed by serial cardiac magnetic resonance imaging (MRI) after a first (clinically evident) ST-elevation MI (STEMI).

METHODS

Within the Etiology, Titre-Course, and effect on Survival (ETiCS) study, cardiac MRI conducted 7-9 days and 12 months after MI enabled longitudinal characterization of patients with a first STEMI along with serial routine blood counts and multiplex cytokine measurements.

RESULTS

Of 91 locally included STEMI patients, 47% were overweight (25 kg/m² < BMI < 30 kg/m²) and 24% were obese (BMI ≥ 30 kg/m²). No patient died during 12 months of follow-up. Left ventricular ejection fraction (LVEF), measured 7-9 days after STEMI, was significantly lower in overweight (49.5 ± 7.1%) and obese (45.8 ± 12.0%) patients than in the normal weight group (56.2 ± 7.7%). Along with BMI (T = -3.8; p < 0.001), hemoglobin A1c (HbA1c; T = -3.1; p = 0.004) and peak C-reactive protein (T = -2.6; p = 0.013) emerged as independent predictors of worse LVEF 7-9 days post MI (R² = 0.45). Only peak C-reactive protein (T = -4.4; p < 0.001), but not parameters of the metabolic syndrome, predicted worse LVEF 12 months after STEMI (R² = 0.20).

CONCLUSION

Both BMI and HbA1c correlated negatively with LVEF only early, but not late after STEMI. Peak CRP evolved as strongest predictor of cardiac function at all time points independent of the metabolic syndrome.

Stakeholder engagement to ensure the sustainability of biobanks: a survey of potential users of biobank services

Biobanks are important infrastructures facilitating biomedical research. After a decade of rolling out such infrastructures, a shift in attention to the sustainability of biobanks could be observed in recent years. In this regard, an increase in the as yet relatively low utilisation rates of biobanks has been formulated as a goal. Higher utilisation rates can only be achieved if the perspectives of potential users of biobanks-particularly researchers not yet collaborating with biobanks-are adequately considered. To better understand their perspectives, a survey was conducted at ten different research institutions in Germany hosting a centralised biobank. The survey targeted potential users of biobank services, i.e. researchers working with biosamples. It addressed the general demand for biosamples, strategies for biosample acquisition/storage and reasons for/against collaborating with biobanks. In total, 354 researchers filled out the survey. Most interestingly, only a minority of researchers (12%) acquired their biosamples via biobanks. Of the respondents not collaborating with biobanks on sample acquisition, around half were not aware of the (services of the) respective local biobank. Those who actively decided against acquiring biosamples via a biobank provided different reasons. Most commonly, respondents stated that the biosamples required were not available, the costs were too high and information about the available biosamples was not readily accessible. Biobanks can draw many lessons from the results of the survey. Particularly, external communication and outreach should be improved. Additionally, biobanks might have to reassess whether their particular collection strategies are adequately aligned with local researchers' needs.

Use of serial changes in biomarkers vs. baseline levels to predict left ventricular remodelling after STEMI

AIMS

Cellular communication network factor 1 (CCN1) is an independent predictor of MACE after ACS and elevated levels correlated with infarct size after STEMI. We compared the prognostic accuracy of baseline levels of CCN1, NT-proBNP, hsTnT, and ST2 and changes in levels over time to predict the development of structural and functional alterations typical of LV remodelling.

METHODS

Serial 3-T cMRI scans were performed to determine LVEF, LVEDV, LVESV, infarct size, and relative infarct size, which were correlated with serial measurements of the four biomarkers. The prognostic significance of these biomarkers was assessed by multiple logistic regression analysis by examining their performance in predicting dichotomized cardiac MRI values 12 months after STEMI based on their median. For each biomarker three models were created using baseline (BL), the Δ value (BL to 6 months), and the two values together as predictors. All models were adjusted for age and renal function. Receiver operator curves were plotted with area under the curve (AUC) to discriminate the prognostic accuracy of individual biomarkers for MRI-based structural or functional changes.

RESULTS

A total of 44 predominantly male patients (88.6%) from the ETiCS (Etiology, Titre-Course, and Survival) study were identified at a mean age of 55.5 ± 11.5 (SD) years treated by successful percutaneous coronary intervention (97.7%) at a rate of 95.5% stent implantation within a median pain-to-balloon time of 260 min (IQR 124-591). Biomarkers hsTnT and ST2 were identified as strong predictors (AUC > 0.7) of LVEDV and LVEF. BL measurement to predict LVEF [hsTnT: AUC 0.870 (95% CI: 0.756-0.983), ST2: AUC 0.763 (95% CI: 0.615-0.911)] and the Δ value BL-6M [hsTnT: AUC 0.870 (95% CI: 0.756-0.983), ST2: AUC 0.809 (95% CI: 0.679-0.939)] showed a high prognostic value without a significant difference for the comparison of the BL model vs. the Δ-value model (BL-6M) for hsTnT (P = 1) and ST2 (P = 0.304). The combined model that included baseline and Δ value as predictors was not able to improve the ability to predict LVEF [hsTnT: AUC 0.891 (0.791-0.992), P = 0.444; ST2: AUC 0.778 (0.638-0.918), P = 0.799]. Baseline levels of CCN1 were closely associated with LVEDV at 12 months [AUC 0.708 (95% CI: 0.551-0.865)] and infarct size [AUC 0.703 (95% CI: 0.534-0.872)].

CONCLUSIONS

Baseline biomarker levels of hsTnT and ST2 were the strongest predictors of LVEF and LVEDV at 12 months after STEMI. The association of CCN1 with LVEDV and infarct size warrants further study into the underlying pathophysiology of this novel biomarker.

[Biobanks, translational research and medical informatics]

When we think of medical research, one intuitively associates it with the analysis of study data collected for a specific research question or with the secondary use of patient data from routine care. However, these are not the only sources for answering scientific questions. Especially for translational research, tissue and liquid samples such as blood, DNA or other body fluids provide essential insights into disease pathogenesis, development of new therapies and treatment decisions. Access to these biomedical materials is provided by so-called biobanks. By collecting, characterizing, documenting and, if necessary, processing human biospecimens in accordance with high quality standards, they can support research of the causes of diseases, early diagnosis and the targeted treatment of diseases, or make a significant contribution to the investigation of common diseases.

Data protection-compliant broad consent for secondary use of health care data and human biosamples for (bio)medical research: Towards a new German national standard

BACKGROUND

The secondary use of deidentified but not anonymized patient data is a promising approach for enabling precision medicine and learning health care systems. In most national jurisdictions (e.g., in Europe), this type of secondary use requires patient consent. While various ethical, legal, and technical analyses have stressed the opportunities and challenges for different types of consent over the past decade, no country has yet established a national consent standard accepted by the relevant authorities.

METHODS

A working group of the national Medical Informatics Initiative in Germany conducted a requirements analysis and developed a GDPR-compliant broad consent standard. The development included consensus procedures within the Medical Informatics Initiative, a documented consultation process with all relevant stakeholder groups and authorities, and the ultimate submission for approval via the national data protection authorities.

RESULTS

This paper presents the broad consent text together with a guidance document on mandatory safeguards for broad consent implementation. The mandatory safeguards comprise i) independent review of individual research projects, ii) organizational measures to protect patients from involuntary disclosure of protected information, and iii) comprehensive information for patients and public transparency. This paper further describes the key issues discussed with the relevant authorities, especially the position on additional or alternative consent approaches such as dynamic consent.

DISCUSSION

Both the resulting broad consent text and the national consensus process are relevant for similar activities internationally. A key challenge of aligning consent documents with the various stakeholders was explaining and justifying the decision to use broad consent and the decision against using alternative models such as dynamic consent. Public transparency for all secondary use projects and their results emerged as a key factor in this justification. While currently largely limited to academic medicine in Germany, the first steps for extending this broad consent approach to wider areas of application, including smaller institutions and medical practices, are currently under consideration.

Metabolite Ratios as Quality Indicators for Pre-Analytical Variation in Serum and EDTA Plasma

In clinical diagnostics and research, blood samples are one of the most frequently used materials. Nevertheless, exploring the chemical composition of human plasma and serum is challenging due to the highly dynamic influence of pre-analytical variation. A prominent example is the variability in pre-centrifugation delay (time-to-centrifugation; TTC). Quality indicators (QI) reflecting sample TTC are of utmost importance in assessing sample history and resulting sample quality, which is essential for accurate diagnostics and conclusive, reproducible research. In the present study, we subjected human blood to varying TTCs at room temperature prior to processing for plasma or serum preparation. Potential sample QIs were identified by Ultra high pressure liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) based metabolite profiling in samples from healthy volunteers (n = 10). Selected QIs were validated by a targeted MS/MS approach in two independent sets of samples from patients (n = 40 and n = 70). In serum, the hypoxanthine/guanosine (HG) and hypoxanthine/inosine (HI) ratios demonstrated high diagnostic performance (Sensitivity/Specificity > 80%) for the discrimination of samples with a TTC > 1 h. We identified several eicosanoids, such as 12-HETE, 15-(S)-HETE, 8-(S)-HETE, 12-oxo-HETE, (±)13-HODE and 12-(S)-HEPE as QIs for a pre-centrifugation delay > 2 h. 12-HETE, 12-oxo-HETE, 8-(S)-HETE, and 12-(S)-HEPE, and the HI- and HG-ratios could be validated in patient samples.

Adaptive anti-myocardial immune response following hospitalization for acute heart failure

Aims

It has been hypothesized that cardiac decompensation accompanying acute heart failure (AHF) episodes generates a pro‐inflammatory environment boosting an adaptive immune response against myocardial antigens, thus contributing to progression of heart failure (HF) and poor prognosis. We assessed the prevalence of anti‐myocardial autoantibodies (AMyA) as biomarkers reflecting adaptive immune responses in patients admitted to the hospital for AHF, followed the change in AMyA titres for 6 months after discharge, and evaluated their prognostic utility.

Methods and results

AMyA were determined in n = 47 patients, median age 71 (quartiles 60; 80) years, 23 (49%) female, and 24 (51%) with HF with preserved ejection fraction, from blood collected at baseline (time point of hospitalization) and at 6 month follow‐up (visit F6). Patients were followed for 18 months (visit F18). The prevalence of AMyA increased from baseline (n = 21, 45%) to F6 (n = 36, 77%; P < 0.001). At F6, the prevalence of AMyA was higher in patients with HF with preserved ejection fraction (n = 21, 88%) compared with patients with reduced ejection fraction (n = 14, 61%; P = 0.036). During the subsequent 12 months after F6, that is up to F18, patients with newly developed AMyA at F6 had a higher risk for the combined endpoint of death or rehospitalization for HF (hazard ratio 4.79, 95% confidence interval 1.13–20.21; P = 0.033) compared with patients with persistent or without AMyA at F6.

Conclusions

Our results support the hypothesis that AHF may induce patterns of adaptive immune responses. More studies in larger populations and well‐defined patient subgroups are needed to further clarify the role of the adaptive immune system in HF progression.

Coagulation factor XIII activity predicts left ventricular remodelling after acute myocardial infarction

AIMS

Acute myocardial infarction (MI) is the major cause of chronic heart failure. The activity of blood coagulation factor XIII (FXIIIa) plays an important role in rodents as a healing factor after MI, whereas its role in healing and remodelling processes in humans remains unclear. We prospectively evaluated the relevance of FXIIIa after acute MI as a potential early prognostic marker for adequate healing.

METHODS AND RESULTS

This monocentric prospective cohort study investigated cardiac remodelling in patients with ST-elevation MI and followed them up for 1 year. Serum FXIIIa was serially assessed during the first 9 days after MI and after 2, 6, and 12 months. Cardiac magnetic resonance imaging was performed within 4 days after MI (Scan 1), after 7 to 9 days (Scan 2), and after 12 months (Scan 3). The FXIII valine-to-leucine (V34L) single-nucleotide polymorphism rs5985 was genotyped. One hundred forty-six patients were investigated (mean age 58 ± 11 years, 13% women). Median FXIIIa was 118% (quartiles, 102-132%) and dropped to a trough on the second day after MI: 109% (98-109%; P < 0.001). FXIIIa recovered slowly over time, reaching the baseline level after 2 to 6 months and surpassed baseline levels only after 12 months: 124% (110-142%). The development of FXIIIa after MI was independent of the genotype. FXIIIa on Day 2 was strongly and inversely associated with the relative size of MI in Scan 1 (Spearman's ρ = -0.31; P = 0.01) and Scan 3 (ρ = -0.39; P < 0.01) and positively associated with left ventricular ejection fraction: ρ = 0.32 (P < 0.01) and ρ = 0.24 (P = 0.04), respectively.

CONCLUSIONS

FXIII activity after MI is highly dynamic, exhibiting a significant decline in the early healing period, with reconstitution 6 months later. Depressed FXIIIa early after MI predicted a greater size of MI and lower left ventricular ejection fraction after 1 year. The clinical relevance of these findings awaits to be tested in a randomized trial.

Towards a comprehensive and interoperable representation of consent-based data usage permissions in the German medical informatics initiative

Background

The aim of the German Medical Informatics Initiative is to establish a national infrastructure for integrating and sharing health data. To this, Data Integration Centers are set up at university medical centers, which address data harmonization, information security and data protection. To capture patient consent, a common informed consent template has been developed. It consists of different modules addressing permissions for using data and biosamples. On the technical level, a common digital representation of information from signed consent templates is needed. As the partners in the initiative are free to adopt different solutions for managing consent information (e.g. IHE BPPC or HL7 FHIR Consent Resources), we had to develop an interoperability layer.

Methods

First, we compiled an overview of data items required to reflect the information from the MII consent template as well as patient preferences and derived permissions. Next, we created entity-relationship diagrams to formally describe the conceptual data model underlying relevant items. We then compared this data model to conceptual models describing representations of consent information using different interoperability standards. We used the result of this comparison to derive an interoperable representation that can be mapped to common standards.

Results

The digital representation needs to capture the following information: (1) version of the consent, (2) consent status for each module, and (3) period of validity of the status. We found that there is no generally accepted solution to represent status information in a manner interoperable with all relevant standards. Hence, we developed a pragmatic solution, comprising codes which describe combinations of modules with a basic set of status labels. We propose to maintain these codes in a public registry called ART-DECOR. We present concrete technical implementations of our approach using HL7 FHIR and IHE BPPC which are also compatible with the open-source consent management software gICS.

Conclusions

The proposed digital representation is (1) generic enough to capture relevant information from a wide range of consent documents and data use regulations and (2) interoperable with common technical standards. We plan to extend our model to include more fine-grained status codes and rules for automated access control.

Unmasking features of the auto-epitope essential for β1 -adrenoceptor activation by autoantibodies in chronic heart failure

Aims

Chronic heart failure (CHF) can be caused by autoantibodies stimulating the heart via binding to first and/or second extracellular loops of cardiac β₁‐adrenoceptors. Allosteric receptor activation depends on conformational features of the autoantibody binding site. Elucidating these features will pave the way for the development of specific diagnostics and therapeutics. Our aim was (i) to fine‐map the conformational epitope within the second extracellular loop of the human β₁‐adrenoceptor (β₁EC_II) that is targeted by stimulating β₁‐receptor (auto)antibodies and (ii) to generate competitive cyclopeptide inhibitors of allosteric receptor activation, which faithfully conserve the conformational auto‐epitope.

Methods and results

Non‐conserved amino acids within the β₁EC_II loop (compared with the amino acids constituting the EC_II loop of the β₂‐adrenoceptor) were one by one replaced with alanine; potential intra‐loop disulfide bridges were probed by cysteine–serine exchanges. Effects on antibody binding and allosteric receptor activation were assessed (i) by (auto)antibody neutralization using cyclopeptides mimicking β₁EC_II ± the above replacements, and (ii) by (auto)antibody stimulation of human β₁‐adrenoceptors bearing corresponding point mutations. With the use of stimulating β₁‐receptor (auto)antibodies raised in mice, rats, or rabbits and isolated from exemplary dilated cardiomyopathy patients, our series of experiments unmasked two features of the β₁EC_II loop essential for (auto)antibody binding and allosteric receptor activation: (i) the NDPK^211–214 motif and (ii) the intra‐loop disulfide bond C²⁰⁹↔C²¹⁵. Of note, aberrant intra‐loop disulfide bond C²⁰⁹↔C²¹⁶ almost fully disrupted the functional auto‐epitope in cyclopeptides.

Conclusions

The conformational auto‐epitope targeted by cardio‐pathogenic β₁‐receptor autoantibodies is faithfully conserved in cyclopeptide homologues of the β₁EC_II loop bearing the NDPK^211–214 motif and the C²⁰⁹↔C²¹⁵ bridge while lacking cysteine C²¹⁶. Such molecules provide promising tools for novel diagnostic and therapeutic approaches in β₁‐autoantibody‐positive CHF.

Prevalence and determinants of the precursor stages of heart failure: results from the population-based STAAB cohort study

Aims

Prevention of heart failure relies on the early identification and control of risk factors. We aimed to identify the frequency and characteristics of individuals at risk of heart failure in the general population.

Methods and Results

We report cross-sectional data from the prospective Characteristics and Course of Heart Failure Stages A–B and Determinants of Progression (STAAB) cohort study investigating a representative sample of residents of Würzburg, Germany. Sampling was stratified 1:1 for sex and 10:27:27:27:10 for age groups of 30–39/40–49/50–59/60–69/70–79 years. Heart failure precursor stages were defined according to American College of Cardiology/American Heart Association: stage A (risk factors for heart failure), stage B (asymptomatic cardiac dysfunction). The main results were internally validated in the second half of the participants. The derivation sample comprised 2473 participants (51% women) with a distribution of 10%/28%/25%/27%/10% in respective age groups. Stages A and B were prevalent in 42% and 17% of subjects, respectively. Of stage B subjects, 31% had no risk factor qualifying for stage A (group ‘B-not-A’). Compared to individuals in stage B with A criteria, B-not-A were younger, more often women, and had left ventricular dilation as the predominant B qualifying criterion (all P &lt; 0.001). These results were confirmed in the validation sample (n = 2492).

Conclusion

We identified a hitherto undescribed group of asymptomatic individuals with cardiac dysfunction predisposing to heart failure, who lacked established heart failure risk factors and therefore would have been missed by conventional primary prevention. Further studies need to replicate this finding in independent cohorts and characterise their genetic and -omic profile and the inception of clinically overt heart failure in subjects of group B-not-A.

Broad donor consent for human biobanks in Germany and Europe: a strategy to facilitate cross-border sharing and exchange of human biological materials and related data

Background

Human biobanks are generally recognized as essential resources for effective biomedical research. All over the world biosamples and data from human subjects are collected in large biobanks. The biological material is stored long term for current and future (undetermined) research issues, which often require cross-border exchange of biosamples and related data.

Content

Commonly, the informed consent for research on human biospecimen is intended to cover only defined, specific research objectives. In June 2016, the biobank Task-Force of the Working Party of the German Medical Ethics Committees (WP-GMEC) updated its template for the broad use of human biological samples and related data. It complies with the current Organisation for Economic Co-operation and Development (OECD) and World Medical Association (WMA) recommendations and furnishes a framework that permits long-term storage and multi-purpose research use of human biological material and related data, including cross-border research.

However, both (i) human biobanks storing and (ii) research projects requesting “broad consent” biological samples generally require an ethical approval; in addition, “broad consent” conditions should be reciprocated by making biobank processes transparent and by fostering both donor and public involvement.

Outlook

The broad consent template of the WP-GMEC clearly states that biological samples and data donated for medical research serve to address current and future research questions. It appears perfectly suited as a template for a Europe-wide harmonized broad consent facilitating biobank-based cross-border research.

Microbiota-derived peptide mimics drive lethal inflammatory cardiomyopathy

Myocarditis can develop into inflammatory cardiomyopathy through chronic stimulation of myosin heavy chain 6–specific T helper (TH)1 and TH17 cells. However, mechanisms governing the cardiotoxicity programming of heart-specific T cells have remained elusive. Using a mouse model of spontaneous autoimmune myocarditis, we show that progression of myocarditis to lethal heart disease depends on cardiac myosin–specific TH17 cells imprinted in the intestine by a commensalBacteroidesspecies peptide mimic. Both the successful prevention of lethal disease in mice by antibiotic therapy and the significantly elevatedBacteroides-specific CD4+T cell and B cell responses observed in human myocarditis patients suggest that mimic peptides from commensal bacteria can promote inflammatory cardiomyopathy in genetically susceptible individuals. The ability to restrain cardiotoxic T cells through manipulation of the microbiome thereby transforms inflammatory cardiomyopathy into a targetable disease.

P5452First data-analysis of the prospective ETiCS-study after study-end confirms acute (microbial-induced) inflammation as a key trigger for the development of cardiac GPCR-autoantibodies

Methods

In total 13 University Hospitals (12 German, 1 Serbian) prospectively recruited 226 patients (pts.) with a first acute myocardial infarction (FAMI), and 140 pts with acute (biopsy- or cMRI-proven) myocarditis (AMitis) into the Etiology, Titer-Course and effect on Survival of cardiac autoantibodies-study (ETiCS-study). This study aimed to investigate whether the presentation of cardiac membrane antigens (e.g., the beta1-adrenoceptor) following cardiac necrosis/inflammation triggers the formation of beta1-aabs. At baseline (BL) and three follow-ups (Fup1–3), blood was sampled to analyze the time-course of beta1-aabs. Beta1-aab titers were measured by FACS using Dyna-beads® M-270-Epoxy coated with increasing amounts of beta1-ECII-peptides (2.5–100 μg/ml), checked versus scrambled peptides (a mixture of same amino-acids). After reacting, the samples were measured by FACScan flow-cytometry; obtained data were analyzed with FlowJo (Treestar). When half-maximal binding was calculable the serum was classified beta1-aab-positive.

Results

From n=366 pts (226 FAMI/140 AMitis) recruited into the ETiCS-study 45 pts had to be excluded because of unperformed cMRI's; 46 pts stopped the study before Fup-1 (month 3). Only 180/226 FAMI- and 98/140 AMitis-pts had complete Fup1–3 (after 3, 6, and 12 months with clinical assessment, echocardiograms, and cMRI's at BL and Fup-3). In all valid ETiCS-pts (197 FAMI-/123 AMitis-pts) the titer-course of beta1-aabs was compared with the development of echo-LVEF. Relevant (high-affinity) beta1-aab-titers were detected in ∼31% (37/123) of the AMitis-pts compared to only ∼21% (42/197) of the FAMI-pts. In aab-positive AMitis-pts echo-LVEF did not recover and was always significantly inferior to aab-negative AMitis-pts (BL: 38 vs. 49% LVEF; Fup-3: 49 vs. 64% LVEF) whereas such a difference was not noted in FAMI-pts. In addition, aab-positive AMitis-pts had higher NT pro-BNP-, renin-, and aldosterone-levels than aab-negative AMitis-pts.

Conclusion

The first evaluation of the completed ETiCS-study clearly suggests that acute microbial-induced rather than post-infarction myocardial inflammation triggers the formation of clinically relevant beta1-aabs. AAb-positive AMitis-patients might profit from early intensification of standard HF-therapy (including early beta-blockade) and/or novel antibody-directed experimental therapies which are currently developed.

Acknowledgement/Funding

BMBF Grant FKZ 01ES0816

P3561Detection and functional characterization of angiotensin receptor type 1 autoantibodies: establishment and clinical translation

Methods

High-throughput screening assays aiming at a reliable detection of AT1R-aabs in sera from patients with HT and PHA were established. The agonist-like activity of AT1R-aabs was assessed by changes in intracellular calcium-levels using Fura2-QBT dye; the AlphaLISA Assay was used to assess induction of ERK1/2-phosphorylation in stably transfected AT1R-HEK-cells or in adrenocortical NCI-H295R cells.

Results

IgG isolated from sera of n=60 patients with PHA and n=164 with HT were screened for their capacity to increase [Ca2+]i or to activate ERK1/2. Sixteen out of 60 PHA-patients increased [Ca2+]i compared to none of the HT-patients, whereas in both disease-entities we detected AT1R-aabs inducing ERK1/2-activation with a similar prevalence (PHA: 41%, HT: 42%), indicating the existence of differentially acting AT1R-aabs. PHA-patients positive for ERK1/2-activating AT1R-aabs have significantly lower serum potassium- (3,8±0,1 vs. 4,1±0,1 mmol/l, p<0,05) and renin-levels (2,7±0,5 vs. 4,5±0,7 ng/l, p<0,05) together with an increased aldosterone concentration (341±37 vs. 236±20 ng/l, p<0,01) concordant with the disease phenotype. Similarly, higher BP values are observed in AT1R-aab positive HT-patients (syst/diast: 148/85 vs. 167/93 mmHg, p<0,0001) accompanied byhigher aldosteroneserum-levels (93±7 vs. 74±3 ng/l, p<0,05).

In addition, ERK1/2-activation induced by either angiotensin II or by IgG isolated from patients with PHA or HT could be differentially blocked by the use of various signaling inhibitors.

In order to elucidate if stimulating AT1R-aabs could be involved in an over-secretion of aldosterone due to sustained receptor-activation, we investigatedtheir effects on NCI-H295R-cells. At the transcriptional level, AT1R-aabs were able to induce a time-dependent upregulation of the key steroidogenic enzymes involved in aldosterone biosynthesis CYP21A1-, HSD3B2-, CYP11B1-, and in particular CYP11B2-mRNA (2fold over basal), with the maximum level achieved after 8 to 12 hours. Concordant withan agonist-stimulated internalization of AT1R,AT1R-mRNA was downregulated by AT1R-aabs (up to 25% of basal) providing direct evidence of a chronic receptor-stimulation by AT1R-aabs.

Conclusion

Functional assays based on AT1R-activation (Ca2+ measurements & ERK1/2-phosphorylation) are able to detect AT1R-aabs in 41% or 42% of patients with HT or PHA, respectively. Moreover, our data provide evidence that AT1R-aabs stabilize a specific AT1R-conformation distinct from that induced by angiotensin II thereby triggering a different intracellular signaling pattern resulting in chronic aldosterone production.

Acknowledgement/Funding

BMBF grant

Longitudinal 18F-FDG PET imaging in a rat model of autoimmune myocarditis

AIMS

Although mortality rate is very high, diagnosis of acute myocarditis remains challenging with conventional tests. We aimed to elucidate the potential role of longitudinal 2-Deoxy-2-18F-fluoro-D-glucose (18F-FDG) positron emission tomography (PET) inflammation monitoring in a rat model of experimental autoimmune myocarditis.

METHODS AND RESULTS

Autoimmune myocarditis was induced in Lewis rats by immunizing with porcine cardiac myosin emulsified in complete Freund's adjuvant. Time course of disease was assessed by longitudinal 18F-FDG PET imaging. A correlative analysis between in- and ex vivo18F-FDG signalling and macrophage infiltration using CD68 staining was conducted. Finally, immunohistochemistry analysis of the cell-adhesion markers CD34 and CD44 was performed at different disease stages determined by longitudinal 18F-FDG PET imaging. After immunization, myocarditis rats revealed a temporal increase in 18F-FDG uptake (peaked at week 3), which was followed by a rapid decline thereafter. Localization of CD68 positive cells was well correlated with in vivo18F-FDG PET signalling (R2 = 0.92) as well as with ex vivo18F-FDG autoradiography (R2 = 0.9, P < 0.001, respectively). CD44 positivity was primarily observed at tissue samples obtained at acute phase (i.e. at peak 18F-FDG uptake), while CD34-positive staining areas were predominantly identified in samples harvested at both sub-acute and chronic phases (i.e. at 18F-FDG decrease).

CONCLUSION

18F-FDG PET imaging can provide non-invasive serial monitoring of cardiac inflammation in a rat model of acute myocarditis.

Quality Assessment of the Preanalytical Workflow in Liquid Biobanking: Taurine as a Serum-Specific Quality Indicator for Preanalytical Process Variations

The scientific impact of translational biomedical research largely depends on the availability of high-quality biomaterials. However, evidence-based and robust quality indicators (QIs) covering the most relevant preanalytical variations are still lacking. The aim of this study was to identify and validate a QI suitable for assessing time-to-centrifugation (TTC) delays in human liquid biospecimens originating from both healthy and diseased individuals. Serum and plasma samples with varying TTCs were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) in a pilot cohort of healthy individuals to identify a suitable QI candidate. Taurine (TAU), as a TTC QI candidate, was validated in healthy individuals and patients with rheumatologic and cardiologic diseases, considering the (1) preanalytical handling temperature, (2) platelet count, and (3) postcentrifugation delay. For discrimination of high TTC (TTC >60 minutes) from low TTC serum specimens, a probability calculation tool was developed (Triple-T-cutoff-model). TTC-dependent changes in healthy individuals were observed for amino acids, particularly TAU. Validation of the TAU levels in an independent cohort of healthy individuals revealed a time-dependent increase in serum, but not in plasma, for a TTC delay of 30-240 minutes. TAU increases were dependent on the handling temperature and platelet count and volume. By contrast, no changes in TAU concentrations were observed for additional postcentrifugation delays. Validation of TAU and the Triple-T-cutoff-model, in rheumatologic/cardiologic patient collectives, allowed the discrimination of samples with TTC ≤60 min/>60 min with estimated AUROC (area under the receiver operating characteristic curve) values of 89% [78%-100%]/86% [71%-100%] and 91% [79%-100%]/84% [68%-100%], respectively. Considering the preanalytical handling temperature and platelet count and volume, TAU and the Triple-T-cutoff-model represent reliable QIs for TTC >60 minutes in serum samples from healthy individuals and selected rheumatologic/cardiologic patients. However, further studies in larger patient collectives with various diseases are needed to assess the robustness and potential of the QIs presented in this article as biobanking quality assurance/quality control tools to support high-quality biomedical research.

Position Statement from the German Biobank Alliance on the Cooperation Between Academic Biobanks and Industry Partners

Under the umbrella of the German Biobank Node (GBN), 11 biobanks and two IT development centers are funded by the Federal Ministry of Education and Research (BMBF) to work together in the German Biobank Alliance (GBA). Their common aim is to make existing biomaterials hosted by different biobanks nationally and internationally available for biomedical research. This position article reflects and summarizes contributions and comments made during a GBA workshop, on the cooperation between academic biobanks and pharmaceutical and diagnostics companies that took place in Leipzig on the 21st of June 2018. It documents key points agreed on by all participating biobanks during the workshop thereby addressing several of the challenges identified. Although there are various possibilities for cooperation between academic biobanks and industry, this position article focuses exclusively on projects where academic biobanks give access to their biosamples and related data to industry partners. In doing so it considers the general conditions/framework and procedures in the German biobanking environment and raises ethical, legal, and procedural issues to be addressed when initiating such collaborations. It intends to furnish a basis for further activities to foster cooperation with industry and to push an overarching national coordination process. The final aim is to develop GBN-recommendations. Of course, many hospitals already have clear regulations on collaboration(s) with industry partners. These naturally take precedence for the GBA biobanks. However, where interest exists, GBN/GBA recommendations could help to induce changes to existing local policies nonetheless.

Real-time Triggered RAdial Single-Shot Inversion recovery for arrhythmia-insensitive myocardial T1 mapping: motion phantom validation and in vivo comparison

PURPOSE

Cardiac T₁ mapping has become an increasingly important imaging technique, contributing novel diagnostic options. However, currently utilized methods are often associated with accuracy problems because of heart rate variations and cardiac arrhythmia, limiting their value in clinical routine. This study aimed to introduce an improved arrhythmia-related robust T₁ mapping sequence called RT-TRASSI (real-time Triggered RAdial Single-Shot Inversion recovery).

METHODS

All measurements were performed on a 3.0T whole-body imaging system. A real-time feedback algorithm for arrhythmia detection was implemented into the previously described pulse sequence. A programmable motion phantom was constructed and measurements with different simulated arrhythmias arranged. T₁ mapping accuracy and susceptibility to artifacts were analyzed. In addition, in vivo measurements and comparisons with 3 prevailing T₁ mapping sequences (MOLLI, ShMOLLI, and SASHA) were carried out to investigate the occurrence of artifacts.

RESULTS

In the motion phantom measurements, RT-TRASSI showed excellent agreement with predetermined reference T₁ values. Percentage scattering of the T₁ values ranged from -0.6% to +1.9% in sinus rhythm and -1.0% to +3.1% for high-grade arrhythmias. In vivo, RT-TRASSI showed diagnostic image quality with only 6% of the acquired T₁ maps including image artifacts. In contrast, more than 40% of the T₁ maps acquired with MOLLI, ShMOLLI, or SASHA included motion artifacts.

CONCLUSION

Accuracy issues because of heart rate variability and arrhythmia are a prevailing problem in current cardiac T₁ mapping techniques. With RT-TRASSI, artifacts can be minimized because of the short acquisition time and effective real-time feedback, avoiding potential data acquisition during systolic heart phase.

Variations in cardiovascular risk factors in people with and without migration background in Germany - Results from the STAAB cohort study

BACKGROUND

About 20% of the German population have a migration background which might influence prevalence of preventable cardiovascular risk factors (CVRF).

METHODS

We report data of the prospective Characteristics and Course of Heart Failure Stages A-B and Determinants of Progression (STAAB) cohort study investigating a representative sample of inhabitants of the City of Würzburg, Germany, aged 30 to 79 years. Individuals without migration background were defined as follows: German as native language, no other native language, and/or born in Germany. All other participants were defined as individuals with migration background.

RESULTS

Of 2473 subjects (51% female, mean age 54 ± 12 years), 291 (12%) reported a migration background: n = 107 (37%) from a country within the EU, n = 117 (40%) from Russia, and n = 67 (23%) from other countries. Prevalence of hypertension, atherosclerotic disease, and diabetes mellitus was similar in individuals with and without migration background. By contrast, prevalence of obesity and metabolic syndrome was significantly higher in individuals with migration background, with the least favourable profile apparent in individuals from Russia (individuals without vs. with migration background: obesity 19 vs. 24%, p < 0.05; odds ratio: EU: 1.6, Russia: 2.2*, other countries: 0.6; metabolic syndrome 18 vs. 21%, p < 0.05; odds ratio: EU: 1.2, Russia: 1.7*, other countries: 1.5; *p < 0.05).

CONCLUSION

Individuals with migration background in Germany might exhibit a higher CVRF burden due to a higher prevalence of obesity and metabolic syndrome. Strategies for primary prevention of heart failure may benefit from deliberately considering the migration background.

Cyclopeptide COR-1 to treat beta1-adrenergic receptor antibody-induced heart failure

RATIONALE

Despite advances in pharmacotherapy, heart failure still incurs significant morbidity and mortality. Stimulating antibodies directed against the secondextracellular loop of the human ß1-adrenergic receptor (anti-ß1EC2) cause myocyte damage and heart failure in rats. This receptor domain is 100% homologous between rats and humans.

OBJECTIVE

ß1EC2-mimicking cyclopeptides (25-meric) markedly improved the development and/or course of anti-ß1EC2-mediated cardiomyopathy. Further developments should be investigated.

METHODS AND RESULTS

The shortened 18-meric cyclic peptide COR-1, in which one of the two disulphide bonds was removed to enable reproducible GMP production, can also be used to treat cardiomyopathic rats. Echocardiography, catheterization and histopathology of the rat hearts revealed that monthly intravenous administrations of COR-1 almost fully reversed the cardiomyopathic phenotype within 6 months at doses of 1 to 4 mg/kg body weight. Administration of COR-1 resulted in markedly reduced anti-ß1EC2-expressing memory B lymphocytes in the spleen despite continued antigenic boosts, but did not significantly decrease overall peripheral anti-ß1EC2 titers. COR-1 did not induce any anti-ß1EC2 or other immune response in naïve rats (corresponding to findings in healthy human volunteers). It did not cause any toxic side effects in GLP studies in dogs, rats or mice, and the "no observed adverse effect level" (NOAEL) exceeded the therapeutic doses by 100-fold.

CONCLUSION

The second generation immunomodulating epitope-mimicking cyclopeptide COR-1 (also termed JNJ-5442840) offers promise to treat immune-mediated cardiac diseases.

Current practices for access, compensation, and prioritization in biobanks. Results from an interview study

Human biological materials and related data stored in biobanks are valuable resources for biomedical research. Transparent, effective, and efficient governance structures and procedures for access, compensation, and priority setting are needed, but recent debates indicate challenges in the practical application of such governance processes. This study aimed to assess the practical experiences and attitudes of biobank experts regarding the governance of biosample access, prioritization, and compensation. Qualitative, semi-structured telephone interviews were conducted with 20 biobank directors from eight countries. Respondents highlighted the need for sound governance structures in order to ensure acceptance by all stakeholders (patients/donors, researchers, research funders, public, and others). They stressed practical difficulties in trying to make best use of biomaterials. As biobanks often form part of larger academic and clinical settings, the different and sometimes conflicting interests of researchers, clinicians, patients, funders, and biobank staff currently affect the governance of access decisions. Investments such as intellectual input, financial, and human resources need to be compensated adequately. Biobanks thereby have a dual role stewarding the hosted biosamples and acting as a service provider for local researchers from universities or hospitals. In order to facilitate efficient use of human biological materials, greater harmonization of at least minimum standards for access and compensation are required at both a national and an international level.

In vivo T2* weighted MRI visualizes cardiac lesions in murine models of acute and chronic viral myocarditis

Objective

Acute and chronic forms of myocarditis are mainly induced by virus infections. As a consequence of myocardial damage and inflammation dilated cardiomyopathy and chronic heart failure may develop. The gold standard for the diagnosis of myocarditis is endomyocardial biopsies which are required to determine the etiopathogenesis of cardiac inflammatory processes. However, new non-invasive MRI techniques hold great potential in visualizing cardiac non-ischemic inflammatory lesions at high spatial resolution, which could improve the investigation of the pathophysiology of viral myocarditis.

Results

Here we present the discovery of a novel endogenous T2* MRI contrast of myocardial lesions in murine models of acute and chronic CVB3 myocarditis. The evaluation of infected hearts ex vivo and in vivo by 3D T2w and T2*w MRI allowed direct localization of virus-induced myocardial lesions without any MRI tracer or contrast agent. T2*w weighted MRI is able to detect both small cardiac lesions of acute myocarditis and larger necrotic areas at later stages of chronic myocarditis, which was confirmed by spatial correlation of MRI hypointensity in myocardium with myocardial lesions histologically. Additional in vivo and ex vivo MRI analysis proved that the contrast mechanism was due to a strong paramagnetic tissue alteration in the vicinity of myocardial lesions, effectively pointing towards iron deposits as the primary contributor of contrast. The evaluation of the biological origin of the MR contrast by specific histological staining and transmission electron microscopy revealed that impaired iron metabolism primarily in mitochondria caused iron deposits within necrotic myocytes, which induces strong magnetic susceptibility in myocardial lesions and results in strong T2* contrast.

Conclusion

This T2*w MRI technique provides a fast and sensitive diagnostic tool to determine the patterns and the severity of acute and chronic enteroviral myocarditis and the precise localization of tissue damage free of MR contrast agents.

A standardised FACS assay based on native, receptor transfected cells for the clinical diagnosis and monitoring of β1-adrenergic receptor autoantibodies in human heart disease

BACKGROUND

Autoantibodies against β1-adrenergic receptors (β1AR) that stimulate cardiac cAMP-production play a causal role in the pathogenesis of human heart failure. Patients can be subjected to specific therapies, if the presence of potentially cardio-noxious β1AR-autoantibodies is reliably diagnosed. This requires assessment of IgG-interactions with the native β1AR because β1AR-autoantibodies target a conformational epitope inadequately presented by denatured receptors or linear peptides. Here, we report on a standardised diagnostic procedure for the assessment of β1AR-autoantibodies in heart failure patients, which is based on IgG-binding to native human β1AR.

METHODS

Good laboratory practice (GLP)-conform measurement of β1AR-autoantibodies was based on flow-cytometric quantification of differential IgG-binding to native HT1080 cells overexpressing biofluorescent human β1AR or not. Receptor-specific IgG-binding was derived from IgG-related median fluorescence of β1AR-positive cells corrected for background staining of β1AR-negative cells admixed to each measurement. The slope of IgG binding at two different concentrations was used as measure for the titre/avidity of β1AR-autoantibodies.

RESULTS

Sensitivity and specificity of the novel procedure for high β1AR-autoantibody levels in dilated cardiomyopathy patients (n=40, NYHA class III-IV) relative to n=40 matched healthy subjects was >90%. It was similar to functional assays considered the gold standard and vastly superior to existing screening-procedures employing fixed cells or linear receptor-peptides as auto-antigenic targets. Inter-assay scatter was 7%-15% and linear dilution recovery was within ±10% of expected values throughout.

CONCLUSIONS

The novel assay possibly provides a tool to determine true prevalence and clinical impact of β1AR-autoantibodies. Furthermore, it may serve as companion diagnostic for therapies specifically directed at β1AR-autoantibodies.

11C-Methionine PET of Myocardial Inflammation in a Rat Model of Experimental Autoimmune Myocarditis

Myocarditis represents a major cause of dilated cardiomyopathy and sudden cardiac death in younger adults. Currently, definitive diagnosis of myocarditis requires endomyocardial biopsy, which is highly invasive and has the drawback of variable sensitivity due to inherent sampling error. Therefore, reliable noninvasive methods to detect and monitor cardiac inflammation are clinically relevant. In this study, we explored the potential of radiolabeled methionine to assess myocardial inflammatory activity in a rat model of experimental autoimmune myocarditis (EAM).

METHODS

Autoimmune myocarditis was induced by immunizing Lewis rats twice with porcine cardiac myosin and Freund complete adjuvant. Control animals were treated with adjuvant alone. Dual-tracer autoradiography was performed to assess ¹⁴C-methionine uptake and to compare the distributions of ¹⁴C-methionine versus ¹⁸F-FDG. Hematoxylin and eosin staining and anti-CD68 macrophage staining were performed for histologic analysis. Additionally, cardiac ¹¹C-methionine PET was performed to evaluate the feasibility of in vivo imaging. ¹⁸F-FDG PET was also conducted to compare the in vivo uptake of ¹¹C-methionine and ¹⁸F-FDG.

RESULTS

Multiple focal cardiac inflammatory lesions were histologically identified in myosin-immunized rats, whereas no cardiac lesions were observed in the controls. Autoradiographic images clearly showed a high-density accumulation of ¹⁴C-methionine in inflammatory lesions of EAM rats, whereas no significant uptake was observed in the control animals. ¹⁴C-methionine uptake was significantly higher in inflammatory lesions than in remote noninflammatory areas and control rat hearts. The distribution of ¹⁴C-methionine correlated well with that of ¹⁸F-FDG and with macrophage density. The contrast between inflammatory and noninflammatory areas was higher for ¹⁸F-FDG than for ¹⁴C-methionine (3.45 ± 0.68 vs. 2.07 ± 0.21, respectively; P < 0.05). In the PET imaging study, the regional ¹¹C-methionine uptake (percentage injected dose per cubic centimeter) observed in EAM rats was significantly higher than the values obtained for control animals (0.64 ± 0.09 vs. 0.28 ± 0.02, respectively; P < 0.001). A good positive correlation between ¹¹C-methionine and ¹⁸F-FDG uptake was found.

CONCLUSION

In a rat model of autoimmune myocarditis, we demonstrated the colocalization of radiolabeled methionine accumulation with ¹⁸F-FDG uptake in histologically proven inflammatory lesions. These data suggest that ¹¹C-methionine might represent a promising candidate for the noninvasive detection and monitoring of myocarditis.

[Establishing and operating a human biobank. Ethical aspects]

Particularly in the past decade which has been marked by efforts to foster individualized/personalized medicine the need for well-characterized high-quality collections of human biological material has significantly increased. When establishing and operating a human biobank the interests and the "freedom" of biomedical research must always be weighed against the interests and rights of patients and/or donors; in this process ethical aspects should be considered systematically. In addition, the importance of quality control and quality assurance has largely increased in human biobanking, both from a scientific and even more from an ethical point of view, because donated biological materials are potentially stored for decades and (on request) might serve for currently not foreseeable biomedical research purposes. In addition, the compatibility of national human biobanks with international biobank networks becomes increasingly important.

Monitoring of monocyte recruitment in reperfused myocardial infarction with intramyocardial hemorrhage and microvascular obstruction by combined fluorine 19 and proton cardiac magnetic resonance imaging

BACKGROUND

Monocytes and macrophages are indispensable in the healing process after myocardial infarction (MI); however, the spatiotemporal distribution of monocyte infiltration and its correlation to prognostic indicators of reperfused MI have not been well described.

METHODS AND RESULTS

With combined fluorine 19/proton ((1)H) magnetic resonance imaging, we noninvasively visualized the spatiotemporal recruitment of monocytes in vivo in a rat model of reperfused MI. Blood monocytes were labeled by intravenous injection of (19)F-perfluorocarbon emulsion 1 day after MI. The distribution patterns of monocyte infiltration were correlated to the presence of microvascular obstruction (MVO) and intramyocardial hemorrhage. In vivo, (19)F/(1)H magnetic resonance imaging performed in series revealed that monocyte infiltration was spatially inhomogeneous in reperfused MI areas. In the absence of MVO, monocyte infiltration was more intense in MI regions with serious ischemia-reperfusion injuries, indicated by severe intramyocardial hemorrhage; however, monocyte recruitment was significantly impaired in MVO areas accompanied by severe intramyocardial hemorrhage. Compared with MI with isolated intramyocardial hemorrhage, MI with MVO resulted in significantly worse pump function of the left ventricle 28 days after MI.

CONCLUSIONS

Monocyte recruitment was inhomogeneous in reperfused MI tissue. It was highly reduced in MVO areas defined by magnetic resonance imaging. The impaired monocyte infiltration in MVO regions could be related to delayed healing and worse functional outcomes in the long term. Therefore, monocyte recruitment in MI with MVO could be a potential diagnostic and therapeutic target that could be monitored noninvasively and longitudinally by (19)F/(1)H magnetic resonance imaging in vivo.

Monitoring of monocyte recruitment in reperfused myocardial infarction with intramyocardial hemorrhage and microvascular obstruction by combined fluorine 19 and proton cardiac magnetic resonance imaging

BACKGROUND

Monocytes and macrophages are indispensable in the healing process after myocardial infarction (MI); however, the spatiotemporal distribution of monocyte infiltration and its correlation to prognostic indicators of reperfused MI have not been well described.

METHODS AND RESULTS

With combined fluorine 19/proton ((1)H) magnetic resonance imaging, we noninvasively visualized the spatiotemporal recruitment of monocytes in vivo in a rat model of reperfused MI. Blood monocytes were labeled by intravenous injection of (19)F-perfluorocarbon emulsion 1 day after MI. The distribution patterns of monocyte infiltration were correlated to the presence of microvascular obstruction (MVO) and intramyocardial hemorrhage. In vivo, (19)F/(1)H magnetic resonance imaging performed in series revealed that monocyte infiltration was spatially inhomogeneous in reperfused MI areas. In the absence of MVO, monocyte infiltration was more intense in MI regions with serious ischemia-reperfusion injuries, indicated by severe intramyocardial hemorrhage; however, monocyte recruitment was significantly impaired in MVO areas accompanied by severe intramyocardial hemorrhage. Compared with MI with isolated intramyocardial hemorrhage, MI with MVO resulted in significantly worse pump function of the left ventricle 28 days after MI.

CONCLUSIONS

Monocyte recruitment was inhomogeneous in reperfused MI tissue. It was highly reduced in MVO areas defined by magnetic resonance imaging. The impaired monocyte infiltration in MVO regions could be related to delayed healing and worse functional outcomes in the long term. Therefore, monocyte recruitment in MI with MVO could be a potential diagnostic and therapeutic target that could be monitored noninvasively and longitudinally by (19)F/(1)H magnetic resonance imaging in vivo.

Current state of knowledge on aetiology, diagnosis, management, and therapy of myocarditis: a position statement of the European Society of Cardiology Working Group on Myocardial and Pericardial Diseases

In this position statement of the ESC Working Group on Myocardial and Pericardial Diseases an expert consensus group reviews the current knowledge on clinical presentation, diagnosis and treatment of myocarditis, and proposes new diagnostic criteria for clinically suspected myocarditis and its distinct biopsy-proven pathogenetic forms. The aims are to bridge the gap between clinical and tissue-based diagnosis, to improve management and provide a common reference point for future registries and multicentre randomised controlled trials of aetiology-driven treatment in inflammatory heart muscle disease.

Administration of the cyclic peptide COR-1 in humans (phase I study): ex vivo measurements of anti-β1-adrenergic receptor antibody neutralization and of immune parameters

AIMS

A novel concept for the treatment of heart failure is the neutralization of antibodies against the β(1)-adrenergic receptor (anti-β(1)AR-ab). In a rat model of autoimmune cardiomyopathy, the cyclic peptide COR-1 (given i.v. once monthly) neutralized anti-β(1)AR-abs and prevented anti-β(1)AR-ab-induced myocardial damage, and completely reverted cardiac dysfunction over 3-6 months.

METHODS AND RESULTS

A clinical phase I trial was designed as a single-blinded, placebo-controlled study. Fifty human volunteers received COR-1 or matching placebo as a single i.v. administration with ascending doses (10-240 mg). Primary endpoints were safety and tolerability, while the pharmacokinetic profile of COR-1 was assessed as a secondary endpoint. All five investigated dose groups were well tolerated; no drug-related side effects occurred. Pharmacokinetics revealed a favourable profile with an almost complete plasma clearance within 60 min after administration. Pharmacodynamic investigation showed dose-dependent efficacy with almost complete scavenging of pathological anti-β(1)AR-abs ex vivo at the two highest doses. No anti-COR-1 autoantibodies occurred. No other effects on the immune system (such as an increase of crucial cytokines) were observed up to 43 days after drug administration, nor upon incubation of anti-β(1)AR-ab-positive patient blood samples with COR-1 ex vivo.

CONCLUSIONS

COR-1 was shown to be safe after i.v. administration in vivo; no relevant side effects occurred. Efficacy was estimated from ex vivo investigation of the potency to neutralize specific anti-β(1)-AR-abs.

TRIAL REGISTRATION

NCT 01043146, Eudra CT 2008-007745-31.

Detection of anti-β1-AR autoantibodies in heart failure by a cell-based competition ELISA

RATIONALE

Autoantibodies directed against the second extracellular loop of the cardiac β1-adrenergic receptor (β1-AR) are thought to contribute to the pathogenesis of dilated cardiomyopathy (DCM) and Chagas heart disease. Various approaches have been used to detect such autoantibodies; however, the reported prevalence varies largely, depending on the detection method used.

OBJECTIVE

We analyzed sera from 167 DCM patients (ejection fraction<45%) and from 110 age-matched volunteers who did not report any heart disease themselves, with an often used simple peptide-ELISA approach, and compared it with a novel whole cell-based ELISA, using cells expressing the full transgene for the human β1-AR. Additionally, 35 patients with hypertensive heart disease with preserved ejection fraction were investigated.

METHODS AND RESULTS

The novel assay was designed according to the currently most reliable anti-TSH receptor antibody-ELISA used to diagnose Graves disease ("third-generation assay") and also detects the target antibodies by competition with a specific monoclonal anti-β1-AR antibody (β1-AR MAb) directed against the functionally relevant β1-AR epitope. Anti-β1-AR antibodies were detected in ≈60% of DCM patients and in ≈8% of healthy volunteers using the same cutoff values. The prevalence of these antibodies was 17% in patients with hypertensive heart disease. Anti-β1-AR antibody titers (defined as inhibition of β1-AR MAb-binding) were no longer detected after depleting sera from IgG antibodies by protein G adsorption. In contrast, a previously used ELISA conducted with a linear 26-meric peptide derived from the second extracellular β1-AR loop yielded a high number of false-positive results precluding any specific identification of DCM patients.

CONCLUSIONS

We established a simple and efficient screening assay detecting disease-relevant β1-AR autoantibodies in patient sera yielding a high reproducibility also in high throughput screening. The assay was validated according to "good laboratory practice" and can serve as a companion biodiagnostic assay for the development and evaluation of antibody-directed therapies in antibody-positive heart failure.

Mode of action and effects of standardized collaborative disease management on mortality and morbidity in patients with systolic heart failure: the Interdisciplinary Network for Heart Failure (INH) study

BACKGROUND

Trials investigating efficacy of disease management programs (DMP) in heart failure reported contradictory results. Features rendering specific interventions successful are often ill defined. We evaluated the mode of action and effects of a nurse-coordinated DMP (HeartNetCare-HF, HNC).

METHODS AND RESULTS

Patients hospitalized for systolic heart failure were randomly assigned to HNC or usual care (UC). Besides telephone-based monitoring and education, HNC addressed individual problems raised by patients, pursued networking of health care providers and provided training for caregivers. End points were time to death or rehospitalization (combined primary), heart failure symptoms, and quality of life (SF-36). Of 1007 consecutive patients, 715 were randomly assigned (HNC: n=352; UC: n=363; age, 69±12 years; 29% female; 40% New York Heart Association class III-IV). Within 180 days, 130 HNC and 137 UC patients reached the primary end point (hazard ratio, 1.02; 95% confidence interval, 0.81-1.30; P=0.89), since more HNC patients were readmitted. Overall, 32 HNC and 52 UC patients died (1 UC patient and 4 HNC patients after dropout); thus, uncensored hazard ratio was 0.62 (0.40-0.96; P=0.03). HNC patients improved more regarding New York Heart Association class (P=0.05), physical functioning (P=0.03), and physical health component (P=0.03). Except for HNC, health care utilization was comparable between groups. However, HNC patients requested counseling for noncardiac problems even more frequently than for cardiovascular or heart-failure-related issues.

CONCLUSIONS

The primary end point of this study was neutral. However, mortality risk and surrogates of well-being improved significantly. Quantitative assessment of patient requirements suggested that besides (tele)monitoring individualized care considering also noncardiac problems should be integrated in efforts to achieve more sustainable improvement in heart failure outcomes.

CLINICAL TRIAL REGISTRATION

URL: http://www.controlled-trials.com. Unique identifier: ISRCTN23325295.

Cardiac beta1-adrenoceptor autoantibodies in human heart disease: rationale and design of the Etiology, Titre-Course, and Survival (ETiCS) Study

AIMS

Evidence for a pathophysiologic relevance of autoimmunity in human heart disease has substantially increased over the past years. Conformational autoantibodies stimulating the cardiac beta1-adrenoceptor (beta1-aabs) are considered of importance in heart failure development and clinical pilot studies have shown their prognostic significance in human 'idiopathic' cardiomyopathy.

METHODS

We recently developed a novel highly sensitive fluorescence-based functional assay to detect stimulating beta1-aabs. We will use this method to assess Etiology, Titre-Course, and effect on Survival (ETiCS) of beta1-aabs in a prospective multicentre study with serial follow-up of patients after a first acute myocarditis or myocardial infarction. Several European core laboratories will jointly study the hypothesis that both disorders may trigger autoimmune reactions leading to the generation of beta1-aabs and/or other heart-directed aabs. Further, sera from healthy controls and well-characterized patient cohorts with dilated, ischaemic, or hypertensive cardiomyopathy will be analysed retrospectively for beta1-aab prevalence, incidence, persistence, and/or clearance.

CONCLUSION

ETiCS is so far the largest clinical diagnostic study projected to address cardiac autoimmunity. It attempts to unravel the pathophysiology of cardiac autoantibody formation and persistence/clearance. ETiCS will enhance current knowledge on autoimmunity in human heart disease and promote endeavours to develop novel therapies targeting cardiac aabs.