Cardiac Involvement in Myotonic Dystrophy Type 2 Patients With Preserved Ejection Fraction

Abstract

H magnetic resonance spectroscopy were performed. Extracellular volume fraction was calculated. Conduction abnormalities were diagnosed based on Groh criteria. LGE located subepicardial basal inferolateral was detectable in 22% of the patients. Extracellular volume was increased in this region and in the adjacent medial inferolateral segment (P=0.03 compared with healthy controls). In 21% of patients with DM2, fat deposits were detectable (all women). The control group showed no abnormalities. Myocardial triglycerides were not different in LGE-positive and LGE-negative subjects (P=0.47). Six patients had indicators for conduction disease (60% of LGE-positive patients and 12.5% of LGE-negative patients). Conclusions-In DM2, subclinical myocardial injury was already detectable in preserved left ventricular ejection fraction.

Expanded CCUG repeat RNA expression in Drosophila heart and muscle trigger Myotonic Dystrophy type 1-like phenotypes and activate autophagocytosis genes

“…DM2 is specifically characterized by the presence of atrophic fibers with nuclear clumps even before the muscle weakness appearance as well as by a predominant type 2 fiber atrophy 59, 60 . In DM2, cardiac abnormalities have also been reported to be similar to those described in DM1, including conduction disturbances, cardiac arrhythmias and sudden death 26, 61–63 . Similarly, the characteristic features of DM that we describe in our DM2 (CCUG-repeat bearing) flies, including muscle and locomotor defects, cardiac dysfunction and reduced survival, were very similar to the characteristics of flies expressing CUG repeats.…”

Native myocardial T1 time can predict development of subsequent anthracycline‐induced cardiomyopathy

“…Motion‐corrected T2 mapping was performed using an established T2 prepared steady‐state free precession technique (3 single‐shot images with T2 preparation times of 0/24/55 ms and voxel size of 1.6 × 1.6 × 6.0 mm) …”

“…Epicardial and endocardial contours in a mid‐ventricular short‐axis slice were traced for T1 and T2 mapping analyses and a 5% safety margin was applied endocardial and epicardial to minimize partial volume effects. Both T2 and T1 maps were quantified as average global values in the analysed slice as previously reported . Visual surveys were evaluated for artefacts before quantification, and segments with relevant artefacts were excluded from analysis (e.g.…”

Targeting the Heart for Risk Assessment in Myotonic Dystrophy

“…Ultimately, the results from Schmacht et al 3 are an important step in solidifying a role for advanced CMR techniques in identifying preclinical abnormalities in cardiac structure and function for improved risk stratification. Realizing the true benefit of CMR-based screening of individuals who carry or are afflicted with muscular dystrophy requires Shah and Semigran CMR Assessment of Myotonic Dystrophy concerted, multidisciplinary efforts involving heart failure, genetics, and advanced imaging expertise in adequately powered clinical studies.…”

“…2 Although investigations of other muscular dystrophies have used cardiac magnetic resonance (CMR) assessments of myocardial tissue structure and its relationship with cardiovascular outcomes, no large investigations of DM2 with comprehensive tissuebased structural phenotypes has been reported. In this issue of Circulation: Cardiovascular Imaging, Schmacht et al 3 provide detailed CMR characterization of subclinical myocardial phenotypes analogous to peripheral skeletal abnormalities present in DM2.…”