title: Myocardial bridging as a common phenotype of hypertrophic cardiomyopathy has no effect on prognosis.
abstract: BACKGROUND
  The prognostic significance of myocardial bridging in hypertrophic cardiomyopathy (HCM) remains controversial. This investigation sought to evaluate the impact of myocardial bridging on prognosis of patients with HCM.
  
  
  METHODS
  A total of 298 adult patients (73% male, mean age, 53 ± 12 years) with HCM were retrospectively enrolled at Fuwai Hospital from 1999 to 2011. Myocardial bridging was evaluated by coronary angiography. Follow-up data were collected by telephone interviews and mailed questionnaires.
  
  
  RESULTS
  Thirty-four (11%, 34/298) patients were determined with myocardial bridging and the middle of left anterior descending artery was the most frequently involved segment (77%, 26/34). Patients with myocardial bridging were younger than those without bridging (48 ± 9 versus 54 ± 12 years, P = 0.001). During the follow-up of 4.2 ± 2.3 years (range, 0.7-12.2 years), the presence of myocardial bridging was not evidently associated with increased risk for all-cause death (P = 0.54), cardiovascular death (P = 0.60), sudden cardiac death (P = 0.53) and deterioration of heart failure (P = 0.84).
  
  
  CONCLUSIONS
  Myocardial bridging was a relatively common morphological component of HCM but not a predictor for adverse clinical outcomes.
authors.affiliation: Departments of Cardiology (TT, Y-LW, B-ZY, RT-H, X-LZ, LS), Sino-German Laboratory for Molecular Medicine (J-ZW, KS, W-LZ, R-TH), and Hypertension Center (RT-H, X-LZ, LS), State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China; and Department of Cardiology (LZ, HS), First Affiliated Hospital of Medical College, Xi'an Jiaotong University, Xi'an, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Tian
authors.forename: Yi-Lu
authors.initials: YL
authors.lastname: Wang
authors.forename: Ji-Zheng
authors.initials: JZ
authors.lastname: Wang
authors.forename: Kai
authors.initials: K
authors.lastname: Sun
authors.forename: Yu-Bao
authors.initials: YB
authors.lastname: Zou
authors.forename: Wei-Li
authors.initials: WL
authors.lastname: Zhang
authors.forename: Ling
authors.initials: L
authors.lastname: Zhu
authors.forename: Hu
authors.initials: H
authors.lastname: Shen
authors.forename: Ru-Tai
authors.initials: RT
authors.lastname: Hui
authors.forename: Xian-Liang
authors.initials: XL
authors.lastname: Zhou
authors.forename: Lei
authors.initials: L
authors.lastname: Song
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002312:Cardiomyopathy, Hypertrophic / Q000175:diagnosis* / Q000453:epidemiology*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D054084:Myocardial Bridging / Q000175:diagnosis* / Q000453:epidemiology*; D010641:Phenotype; D011379:Prognosis; D012189:Retrospective Studies; D055815:Young Adult