Background: Recent evidence points towards the fact that cardiac troponins might be elevated following skeletal muscle injury and regeneration in patients with chronic myopathies. The “Heart and Muscle” Study is a prospective, observational, multicenter study enrolling patients with a broad spectrum of chronic skeletal muscle diseases. The aim of this study is to determine the prevalence and source of elevated cardiac troponin T and I in the systemic circulation in these patients. Trial Registration No: NCT03660969 (clinicaltrials.gov) Link Type: Investigator initiated Trial Status: Enrollment active, ongoing data analysis Enrolling Centers: Switzerland: Austria: University Hospital Basel University Hospital Innsbruck Cantonal Hospital Aarau Core Study Team Basel: