Observational Study on Cardiac Biomarkers Testing in Patients With Muscular Dystrophy Cardiomyopathy

Study Overview
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Brief Summary
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The objective of this study is to evaluate acute changes of cardiac troponin (and other cardiac biomarkers) and mid-term biovariability in patients with cardiomyopathy associated with chronic skeletal muscle disease. The specific aims of the study are: Firstly, to evaluate the feasibility of the ESC 0/1 hour protocol for rule-in and rule-out of a non-ST-segment elevation acute coronary syndrome (NSTE-ACS). Secondly, a) to determine reference change values (RCV) to characterize physiological biovariability, b) to differentiate acute from chronic high-sensitivity cardiac troponin T (hs-cTnT) elevations.

Detailed Description
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In patients with skeletal muscle dystrophy, cardiac involvement is one of the limiting factors regarding mortality. Early detection of a dystrophy-associated cardiomyopathy is important, as heart failure therapy can slow adverse cardiac remodeling and alleviate heart failure symptoms. Cardiac biomarkers, especially high-sensitivity cardiac Troponin T (hs-cTnT) and to a lesser extent, high-sensitivity cardiac Troponin I (hs-cTnI), are chronically elevated in diseases with underlying structural heart disease. However, there is no reliable data on whether changes in the concentration of cardiac Troponin T or I are suitable for monitoring the cardiac disease progression. This can lead to delayed diagnosis and treatment of a relevant deterioration of the disease or even acute heart muscle damage in the context of acute myocardial infarction, pulmonary embolism, and myocarditis. Due to insufficient clinical data, the feasibility and safety of the ESC 0/1-hour protocol according to the ESC guidelines for the diagnosis of acute myocardial infarction in this patient population are uncertain. Furthermore, it is necessary to determine the normal biovariability of high-sensitivity cardiac Troponin T (hs-cTnT) and high-sensitivity cardiac Troponin I (hs-cTnI) to differentiate physiological concentration fluctuations of these cardiac biomarkers in this patient population from changes that represent an improvement or deterioration of heart function. Routine blood samples that will be collected at presentation, a second blood sample for study purposes will be collected after 1 hour for the first index visit. On the routine follow-up visit, 20 ml of blood will be collected for storage in addition to the routine blood test. Blood samples will be obtained by standard venous blood sampling. If venipuncture is unsuccessful or considered harmful by the patient and a suitable peripheral venous catheter is available, the venous catheter may be used for blood sampling to minimize damage. Assessment of parameters includes demographics and clinical characteristics (symptoms, history, medication, vital signs, risk scores etc.) and laboratory values with special focus on findings related to myocardial injury as indicated by high sensitivity cardiac troponin T (hs-cTnT) and hs-cTnI. Moreover, the laboratory panel comprises other cardiac biomarkers, electrolytes, renal (creatine, glomerular filtration rate) and liver function (GOT, GPT, LDH), C-reactive protein, D-dimer etc.

Official Title
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Observational Study on Cardiac Biomarkers Testing in Patients With Muscular Dystrophy Cardiomyopathy and Assessing the Feasibility of Serial Cardiac Troponin Testing at 0 Hour and 1 Hour, as Well as the Mid-term Biovariability of Cardiac Troponin

Conditions
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Cardiomyopathies, Skeletal Muscle Disorder

Intervention / Treatment
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* Other: No intervention is planned.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Written informed consent Diagnosed muscular dystrophy Patients >18 years of age Exclusion Criteria: Patients with poor venous status Hemodialysis Lack of capacity to provide informed consent or refusal

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: No intervention is planned.|No intervention is planned.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prevalence of stable troponin kinetics in patients | The first main objective is to determine the prevalence of stable troponin kinetics defined as high-sensitivity Troponin T (hour 0) : high-sensitivity Troponin T (hour 1) < 5 ng/l at baseline presentation. | 1 hour | 
| Reference Change Values calculation for cardiac biomarkers | The second main objective is to calculate the Reference Change Values (RCV) of high-sensitivity Troponin T within the 6-month follow-up period. | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Longitudinal follow-up of novel laboratory biomarkers for prognostic significance. | Thirdly, longitudinal follow-up of the patients will be conducted once a year to clarify the prognostic significance of novel laboratory biomarkers. | unlimited |