title: Comparison of Clinical Features in Blacks Versus Whites With Hypertrophic Cardiomyopathy.
abstract: To date, there has not been a large systematic examination of the hypertrophic cardiomyopathy (HC) phenotype in blacks versus whites. In this study, we investigate differences in presentation of HC between blacks and whites. We included 441 consecutive patients with HC seen at the Johns Hopkins HC clinic in the period from February 2005 to June 2012. We compared 76 blacks for clinical presentation, electrocardiogram, exercise capacity, left ventricular morphology, and hemodynamics by echocardiography to 365 whites. Black patients with HC more often presented with abnormal electrocardiogram (93% vs 80%, p = 0.009), driven by a significant difference in repolarization abnormalities (79% vs 56%, p <0.001). Apical hypertrophy was more common in blacks (26% vs 9%, p <0.001); however, blacks had less severe systolic anterior movement of the mitral valve and had significantly lower left ventricular outflow tract gradients at rest (9 mm Hg; interquartile range [IQR] 7 to 19 vs 16 mm Hg; IQR 8 to 40, p <0.001) and during provocation (36 mm Hg; IQR 16 to 77 vs 59 mm Hg; IQR 26 to 110, p = 0.002). Despite the nonobstructive pathophysiology, blacks had lower exercise capacity (adjusted difference 1.45 metabolic equivalents [0.45 to 2.45], p = 0.005). In conclusion, blacks have an HC phenotype characterized by lower prevalence of the well-recognized echocardiographic features of HC such as systolic anterior movement of the mitral valve and left ventricular outflow tract obstruction and display worse exercise capacity.
authors.affiliation: Division of Cardiology, Johns Hopkins HCM Center of Excellence, Baltimore, Maryland; Department of Cardiology, Gentofte Hospital, Copenhagen, Denmark.
authors.forename: Lars L
authors.initials: LL
authors.lastname: Sorensen
authors.affiliation: Division of Cardiology, Johns Hopkins HCM Center of Excellence, Baltimore, Maryland.
authors.forename: Aurelio
authors.initials: A
authors.lastname: Pinheiro
authors.affiliation: Division of Cardiology, Johns Hopkins HCM Center of Excellence, Baltimore, Maryland.
authors.forename: Veronica Lea
authors.initials: VL
authors.lastname: Dimaano
authors.affiliation: Division of Cardiology, Johns Hopkins HCM Center of Excellence, Baltimore, Maryland.
authors.forename: Iraklis
authors.initials: I
authors.lastname: Pozios
authors.affiliation: Division of Cardiology, Johns Hopkins HCM Center of Excellence, Baltimore, Maryland.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Nowbar
authors.affiliation: Division of Cardiology, Johns Hopkins HCM Center of Excellence, Baltimore, Maryland.
authors.forename: Hongyun
authors.initials: H
authors.lastname: Liu
authors.affiliation: Division of Cardiology, Johns Hopkins HCM Center of Excellence, Baltimore, Maryland.
authors.forename: Hong-Chang
authors.initials: HC
authors.lastname: Luo
authors.affiliation: Division of Cardiology, Johns Hopkins HCM Center of Excellence, Baltimore, Maryland.
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Lin
authors.affiliation: Department of Cardiology, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Niels T
authors.initials: NT
authors.lastname: Olsen
authors.affiliation: Department of Cardiology, Gentofte Hospital, Copenhagen, Denmark.
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Hansen
authors.affiliation: Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Sogaard
authors.affiliation: Division of Cardiology, Johns Hopkins HCM Center of Excellence, Baltimore, Maryland.
authors.forename: Maria R
authors.initials: MR
authors.lastname: Abraham
authors.affiliation: Division of Cardiology, Johns Hopkins HCM Center of Excellence, Baltimore, Maryland. Electronic address: tabraha3@jhmi.edu.
authors.forename: Theodore P
authors.initials: TP
authors.lastname: Abraham
mesh_terms: D001741:Black or African American; D002312:Cardiomyopathy, Hypertrophic / Q000175:diagnosis / Q000208:ethnology* / Q000503:physiopathology; D003430:Cross-Sectional Studies; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008396:Maryland / Q000453:epidemiology; D008875:Middle Aged; D009017:Morbidity / Q000639:trends; D010641:Phenotype; D011379:Prognosis; D011446:Prospective Studies; D012042:Registries; D013997:Time Factors; D044465:White People