Structural and electrical cardiac abnormalities are prevalent in asymptomatic adults with myotonic dystrophy

Objective Cardiac disease accounts for a large burden of premature mortality and morbidity in patients with type 1 myotonic dystrophy (MD). However, little is known about structural cardiac abnormalities particularly in asymptomatic patients with MD. We sought to describe the prevalence and extent of structural cardiac abnormalities in patients with MD and to assess their association with functional, electrical, biochemical and genetic disturbances. Methods In this case-control study, 40 adults with MD who had no contraindications to cardiac MRI (CMR) were identified from the Grampian region genetic database. Forty-one age-And-gender-matched healthy volunteers were also recruited. All subjects underwent detailed assessment including CMR, echocardiography, electrocardiography, signal-Averaged electrocardiography, Holter monitoring and quantification of serum B-Type natriuretic peptide (BNP). Genetic testing of patients with MD was performed with quantification of CTG trinucleotide repeat sequences. Results of clinical, electrical, genetic and biochemical investigations were correlated with cardiac structural and functional abnormalities detected on CMR. Results Electrical disturbances including prolongation of PR (187±29 vs 156±23 ms, p