title: Ultrasound tissue characterization does not differentiate genotype, but indexes ejection fraction deterioration in becker muscular dystrophy.
abstract: The aims of the study were, first, to assess whether myocardial ultrasound tissue characterization (UTC) in Becker muscular dystrophy (BMD) can be used to differentiate between patients with deletions and those without deletions; and second, to determine whether UTC is helpful in diagnosing the evolution of left ventricular dysfunction, a precursor of dilated cardiomyopathy. Both cyclic variation of integrated backscatter and calibrated integrated backscatter (cIBS) were assessed in 87 patients with BMD and 70 controls. The average follow-up in BMD patients was 48 ± 12 mo. UTC analysis was repeated only in a subgroup of 40 BMD patients randomly selected from the larger overall group (15 with and 25 without left ventricular dysfunction). Discrimination between BMD patients with and without dystrophin gene deletion was not possible on the basis of UTC data: average cvIBS was 5.2 ± 1.2 and 5.5 ± 1.4 dB, and average cIBS was 29.9 ± 4.7 and 29.6 ± 5.8, respectively, significantly different (p < 0.001) only from controls (8.6 ± 0.5 and 24.6 ± 1.2 dB). In patients developing left ventricular dysfunction during follow-up, cIBS increased to 31.3 ± 5.4 dB, but not significantly (p = 0.08). The highest cIBS values (34.6 ± 5.3 dB, p < 0.09 vs. baseline, p < 0.01 vs BMD patients without left ventricular dysfunction) were seen in the presence of severe left ventricular dysfunction. Multivariate statistics indicated that an absolute change of 6 dB in cIBS is associated with a high probability of left ventricular dysfunction. UTC analysis does not differentiate BMD patients with or without dystrophin gene deletion, but may be useful in indexing left ventricular dysfunction during follow-up.
authors.affiliation: Centre for Neuromuscular Diseases, Unione Italiana Lotta alla Distrofia Muscolare (UILDM), Rome, Italy; Cardiology Division and ICU, Ospedale San Paolo, Civitavecchia, Rome, Italy. Electronic address: giglio.echo@libero.it.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Giglio
authors.affiliation: Laboratory of Biotechnologies Applied to Cardiovascular Medicine, Department of Cardiovascular, Respiratory, Nephrological and Geriatrical Sciences, La Sapienza, University of Rome, Rome, Italy.
authors.forename: Paolo Emilio
authors.initials: PE
authors.lastname: Puddu
authors.affiliation: Physics Department, Washington University, St Louis, Missouri, USA.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Holland
authors.affiliation: Cardiology Division and ICU, Ospedale Madre Giuseppina Vannini, Rome, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Camastra
authors.affiliation: Cardiology Division and ICU, Ospedale Madre Giuseppina Vannini, Rome, Italy.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Ansalone
authors.affiliation: Centre for Neuromuscular Diseases, Unione Italiana Lotta alla Distrofia Muscolare (UILDM), Rome, Italy; Neurology Institute, Catholic University, Rome, Italy.
authors.forename: Enzo
authors.initials: E
authors.lastname: Ricci
authors.affiliation: Muscular Dystrophy Research Unit, UILDM, Rome, Italy.
authors.forename: Julia
authors.initials: J
authors.lastname: Mela
authors.affiliation: Centre for Neuromuscular Diseases, Unione Italiana Lotta alla Distrofia Muscolare (UILDM), Rome, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Sciarra
authors.affiliation: Cardiology Division and ICU, Ospedale San Paolo, Civitavecchia, Rome, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Di Gennaro
mesh_terms: D000293:Adolescent; D000328:Adult; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D016189:Dystrophin / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics; D005838:Genotype; D006801:Humans; D008297:Male; D020388:Muscular Dystrophy, Duchenne / Q000000981:diagnostic imaging* / Q000235:genetics*; D017354:Point Mutation / Q000235:genetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013318:Stroke Volume / Q000235:genetics*; D014463:Ultrasonography / Q000379:methods*; D055815:Young Adult
chemical_list: C484258:DMD protein, human; D016189:Dystrophin
keywords: Becker muscular dystrophy; Cardiomyopathy; Genetics; Myocardial tissue characterization