title: Comparison of clinical, morphological, and prognostic features in hypertrophic cardiomyopathy between Japanese and western patients.
abstract: Apical hypertrophic cardiomyopathy appears to be more common in Japan than in the West. Explanations for this difference include variable methods and criteria for the diagnosis. To assess morphological, clinical, and prognostic differences, 45 consecutive Japanese and 45 age- and gender-matched Western patients with hypertrophic cardiomyopathy were evaluated in two referral institutions by the same individuals. The diagnosis of hypertrophic cardiomyopathy was based on the echocardiographic demonstration of unexplained left ventricular hypertrophy. Patients were aged 8 to 64 years (mean 50); there were 66 males and 24 females. The pattern of left ventricular hypertrophy was similar in Japanese and Western patients: asymmetric septal 64 vs. 76%, concentric 22 vs. 13%, and apical 13 vs. 11% (p = NS). The incidence of an echocardiographic or Doppler calculated left ventricular gradient of > 30 mmHg was similar (11 vs. 18%; p = NS). The maximal left ventricular wall thickness was greater in Western patients (23 +/- 7 vs. 20 +/- 4 mm; p = 0.03), but was not different when adjusted for body surface area. Clinical features including incidence of family history and ventricular tachycardia during 24-h ambulatory electrocardiography were similar. During follow-up (4.9 +/- 4.0 years for Western vs. 4.4 +/- 2.0 years for Japanese), disease-related mortality was worse in Western patients (p < 0.05; 10 versus 2 patients). This evaluation, using the same diagnostic methods and criteria, reveals a worse prognosis in Western patients despite a similar clinical and morphological spectrum of hypertrophic cardiomyopathy.
authors.affiliation: Department of Cardiological Sciences, St. George's Hospital Medical School, London, U.K.
authors.forename: T
authors.initials: T
authors.lastname: Chikamori
authors.forename: Y L
authors.initials: YL
authors.lastname: Doi
authors.forename: M
authors.initials: M
authors.lastname: Akizawa
authors.forename: Y
authors.initials: Y
authors.lastname: Yonezawa
authors.forename: T
authors.initials: T
authors.lastname: Ozawa
authors.forename: W J
authors.initials: WJ
authors.lastname: McKenna
mesh_terms: D000293:Adolescent; D000328:Adult; D001794:Blood Pressure; D002312:Cardiomyopathy, Hypertrophic / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000503:physiopathology; D002648:Child; D015150:Echocardiography, Doppler; D015716:Electrocardiography, Ambulatory; D005060:Europe / Q000453:epidemiology; D005080:Exercise Test; D005260:Female; D006339:Heart Rate; D006346:Heart Septum / Q000000981:diagnostic imaging*; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies