title: Apical left ventricular myocardial dysfunction is an early feature of cardiac involvement in myotonic dystrophy type 1.
abstract: BACKGROUND
  Left ventricular (LV) dysfunction is a major prognostic determinant in myotonic dystrophy type 1 (DM1). Therefore, markers of early-stage LV impairment may be useful. The aim of this study was to evaluate 2D echocardiographic LV strain in a cohort of DM1 patients with preserved left ventricular ejection fraction (LVEF) and to compare the results with matched controls.
  
  
  METHODS
  This prospective single-center study included 33 consecutive DM1 patients between February 2014 and February 2015. Mean age was 38.2±12.9 years, and 17 (52%) were males. Exclusion criteria were LVEF <55%, QRS >120 milliseconds, history of atrial fibrillation, and presence of a pacemaker with ventricular pacing. DM1 patients were matched to healthy controls according to sex and age.
  
  
  RESULTS
  DM1 patients showed significant impairment of global longitudinal strain (GLS) as compared to controls (-18.0±1.9 vs -19.1±2.4; P=.03), characterized by a marked alteration at the apex (-20.0±3.3 vs -22.7±3.1; P<.001). DM1 patients had also global radial strain impairment (20.0±9.8 vs 27.5±14.9; P=.024) compared to controls while global circumferential strain was not statistically different between groups (P=.94). Intra- and inter-observer analysis showed good reproducibility of GLS.
  
  
  CONCLUSIONS
  Despite preserved LVEF, DM1 patients exhibited significantly altered LV GLS, particularly at the apex, as compared with controls. The detection of impaired myocardial deformation at early stages of the disease might help to screen high-risk patients who need closer follow-up.
authors.affiliation: Cardiology Service, CHU Poitiers, Poitiers, France.
authors.forename: Rodrigue
authors.identifier: http://orcid.org/0000-0001-9350-2437
authors.initials: R
authors.lastname: Garcia
authors.affiliation: Cardiology Service, CHU Poitiers, Poitiers, France.
authors.forename: Quentin
authors.initials: Q
authors.lastname: Labarre
authors.affiliation: Cardiology Service, CHU Poitiers, Poitiers, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Degand
authors.affiliation: University of Medicine and Pharmacy, Poitiers University, Poitiers, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Ingrand
authors.affiliation: Cardiology Service, CHU Poitiers, Poitiers, France.
authors.forename: François
authors.initials: F
authors.lastname: Le Gal
authors.affiliation: Cardiology Service, CHU Poitiers, Poitiers, France.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Bonnet
authors.affiliation: Rehabilitation Department, CHU Poitiers, Poitiers, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Delaubier
authors.affiliation: Rehabilitation Department, CHU Poitiers, Poitiers, France.
authors.forename: Claire
authors.initials: C
authors.lastname: Guillou
authors.affiliation: Cardiology Service, CHU Poitiers, Poitiers, France.
authors.forename: Barnabas
authors.initials: B
authors.lastname: Gellen
authors.affiliation: Cardiology Service, CHU Poitiers, Poitiers, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Coisne
authors.affiliation: Cardiology Department, Assistance Publique des Hopitaux de Paris, Hôpital Bichat Service de Cardiologie, Paris, France.
authors.forename: Claire
authors.initials: C
authors.lastname: Bouleti
authors.affiliation: Cardiology Service, CHU Poitiers, Poitiers, France.|University of Medicine and Pharmacy, Poitiers University, Poitiers, France.
authors.forename: Luc
authors.initials: L
authors.lastname: Christiaens
mesh_terms: D000328:Adult; D004452:Echocardiography; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008297:Male; D009223:Myotonic Dystrophy / Q000150:complications* / Q000503:physiopathology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D018487:Ventricular Dysfunction, Left / Q000150:complications* / Q000000981:diagnostic imaging* / Q000503:physiopathology
keywords: 2D echocardiography; cardiomyopathy; left ventricular function; multilayer speckle tracking; myotonic dystrophy type 1; strain