title: Relationship of myocardial fibrosis to left ventricular and mitochondrial function in nonischemic dilated cardiomyopathy--a comparison of focal and interstitial fibrosis.
abstract: BACKGROUND
  Mitochondrial damage is associated with histologic myocardial fibrosis. Late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) can be used to identify focal fibrosis. We examined whether myocardial fibrosis on CMR and collagen volume fraction (CVF) from biopsies correlated with left ventricular (LV) and mitochondrial function in patients with nonischemic dilated cardiomyopathy (DCM).
  
  
  RESULTS
  Fifty-nine DCM patients underwent CMR, cardiac catheterization, and endomyocardial biopsy. Minimum first derivative of LV pressure (LVdP/dt(min)) was measured as an index of LV relaxation. Mitochondrial RNA expression was also analyzed. For quantitative analysis of myocardial fibrosis, percentage LGE (%LGE) and CVF were calculated. Patients were divided into 2 groups on the basis of the presence (LGE group; n = 27) or absence (non-LGE group; n = 32) of LGE. Mean CVF and absolute value of LVdP/dt(min) were significantly higher and lower, respectively, in the LGE group than in the non-LGE group. Multivariate analysis revealed that %LGE was an independent determinant of LVdP/dt(min). The abundance of mitochondrial enzyme mRNA was significantly lower in the LGE group.
  
  
  CONCLUSIONS
  Noninvasive CMR imaging is more useful in predicting diastolic dysfunction than invasive histologic assessments. In addition, it might indicate mitochondrial dysfunction in DCM.
authors.affiliation: Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamada
authors.forename: Akihiro
authors.initials: A
authors.lastname: Hirashiki
authors.forename: Xian Wu
authors.initials: XW
authors.lastname: Cheng
authors.forename: Takahiro
authors.initials: T
authors.lastname: Okumura
authors.forename: Shuzo
authors.initials: S
authors.lastname: Shimazu
authors.forename: Rie
authors.initials: R
authors.lastname: Okamoto
authors.forename: Norihiro
authors.initials: N
authors.lastname: Shinoda
authors.forename: Satoshi
authors.initials: S
authors.lastname: Isobe
authors.forename: Kyosuke
authors.initials: K
authors.lastname: Takeshita
authors.forename: Shinji
authors.initials: S
authors.lastname: Naganawa
authors.forename: Takahisa
authors.initials: T
authors.lastname: Kondo
authors.forename: Toyoaki
authors.initials: T
authors.lastname: Murohara
mesh_terms: D000328:Adult; D000368:Aged; D002311:Cardiomyopathy, Dilated / Q000175:diagnosis* / Q000503:physiopathology*; D005260:Female; D005355:Fibrosis; D006801:Humans; D008297:Male; D008875:Middle Aged; D008929:Mitochondria, Heart / Q000502:physiology*; D009206:Myocardium / Q000473:pathology*; D011446:Prospective Studies; D016277:Ventricular Function, Left / Q000502:physiology*
keywords: Cardiomyopathy; diastolic function; magnetic resonance imaging; mitochondria