title: Cardiac muscle cell disorganization in apical hypertrophic cardiomyopathy: a cardiac biopsy study.
abstract: Apical hypertrophic cardiomyopathy has been divided into two entities: apical asymmetric septal hypertrophy (apical ASH) and apical symmetric hypertrophy (AH). The latter differs clinically from hypertrophic cardiomyopathy (HCM) with ASH, and it is unclear whether AH represents a distinct subtype of HCM. In the present study, the presence or absence and the extent of cardiac muscle cell disorganization, a histologic characteristic of HCM, were compared in patients with AH (n = 10) and ASH (n = 29) in whom cardiac biopsy specimens were obtained from the left ventricular apex and interventricular septum. Disorganization was graded as (1+) in only 1 patient in the AH group and (-) in the remaining 9. In contrast, in the ASH group disorganization was graded as (1+) in 15 patients, (2+) in 7, (3+) in 3, and (-) in only 4 (P < 0.0001). Thus, it was observed that in AH disorganization is virtually absent or at most limited to a very narrow area. It is concluded from a histological stand point as well that the type of apical hypertrophic cardiomyopathy showing apical symmetric hypertrophy differs from usual HCM.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, Fujita Health University School of Medicine, Toyoake, Aichi, Japan.
authors.forename: Shin-ichiro
authors.initials: S
authors.lastname: Morimoto
authors.forename: Morie
authors.initials: M
authors.lastname: Sekiguchi
authors.forename: Akihisa
authors.initials: A
authors.lastname: Uemura
authors.forename: Shinya
authors.initials: S
authors.lastname: Hiramitsu
authors.forename: Katsutomo
authors.initials: K
authors.lastname: Kimura
authors.forename: Masatsugu
authors.initials: M
authors.lastname: Ohtsuki
authors.forename: Junichi
authors.initials: J
authors.lastname: Ishii
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kato
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kasanuki
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Hishida
mesh_terms: D001706:Biopsy; D002312:Cardiomyopathy, Hypertrophic / Q000000981:diagnostic imaging / Q000235:genetics / Q000473:pathology*; D004452:Echocardiography; D004562:Electrocardiography; D006352:Heart Ventricles / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009206:Myocardium / Q000473:pathology*; D032383:Myocytes, Cardiac / Q000473:pathology*