title: Myocardial repolarization dispersion and late gadolinium enhancement in patients with hypertrophic cardiomyopathy.
abstract: BACKGROUND
  Growing evidence suggests that late gadolinium enhancement (LGE) at cardiac magnetic resonance (CMR) is an additive marker of disease severity, and possibly of arrhythmic risk, in hypertrophic cardiomyopathy (HCM). We investigated the possible relationship between LGE and markers of myocardial repolarization dispersion in HCM.
  
  
  RESULTS
  Eighty-five HCM outpatients underwent CMR and short-period electrocardiogram analysis to calculate the temporal myocardial repolarization dispersion through the QT variance normalized for QT mean (QTVN) and the QT variability index (QTVI). The QT dispersion in the spatial domain was also obtained. Patients with LGE (62%) had higher left atrial volume, maximum wall thickness, and left ventricular mass (P<0.0001), as well as a greater prevalence of non-sustained ventricular tachycardia (P<0.0001) and hypotensive blood pressure response (P=0.044). Both QTVN and QTVI were higher in the group with LGE (P<0.0001). At multivariate analysis, using QTVI as the dependent variable, %LGE (P<0.0001), age (P<0.0001), left ventricular outflow obstruction (P=0.038), and sudden cardiac death risk factor burden (P=0.020) reached statistical significance. Otherwise, only %LGE (P=0.005) and left ventricular mass index (P=0.015) remained associated with QTVN.
  
  
  CONCLUSIONS
  Temporal myocardial repolarization dispersion correlates with LGE extent. Whether these variables could be useful in HCM clinical management warrants confirmation by larger prospective studies.
authors.affiliation: Department of Clinical and Molecular Medicine, Sapienza University.
authors.forename: Damiano
authors.initials: D
authors.lastname: Magrì
authors.forename: Carlo Nicola
authors.initials: CN
authors.lastname: De Cecco
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Piccirillo
authors.forename: Vittoria
authors.initials: V
authors.lastname: Mastromarino
authors.forename: Andrea
authors.initials: A
authors.lastname: Serdoz
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Muscogiuri
authors.forename: Agnese
authors.initials: A
authors.lastname: Ricotta
authors.forename: Mario
authors.initials: M
authors.lastname: Gregori
authors.forename: Laura
authors.initials: L
authors.lastname: Marino
authors.forename: Filippo Maria
authors.initials: FM
authors.lastname: Cauti
authors.forename: Erika
authors.initials: E
authors.lastname: Pagannone
authors.forename: Maria Beatrice
authors.initials: MB
authors.lastname: Musumeci
authors.forename: Antonello
authors.initials: A
authors.lastname: Maruotti
authors.forename: Camillo
authors.initials: C
authors.lastname: Autore
mesh_terms: D000328:Adult; D000367:Age Factors; D002312:Cardiomyopathy, Hypertrophic / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D004562:Electrocardiography; D005260:Female; D005682:Gadolinium / Q000008:administration & dosage*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009206:Myocardium; D011859:Radiography; D017180:Tachycardia, Ventricular / Q000000981:diagnostic imaging / Q000503:physiopathology
chemical_list: D005682:Gadolinium