title: Myocardial fibrosis progression on cardiac magnetic resonance in hypertrophic cardiomyopathy.
abstract: OBJECTIVE
  We hypothesised that, in hypertrophic cardiomyopathy (HCM), late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) is progressive and can be predicted by baseline CMR findings and HCM phenotype.
  
  
  METHODS
  In this single-centre cohort study, 71 patients with HCM (59±13 years; 48 men) were prospectively enrolled with clinical, echocardiographic and CMR data. Two consecutive CMR scans were performed with a time interval of 582±174 days. The LGE extent was quantified as a proportion of total LV myocardium (%LGE).
  
  
  RESULTS
  LGE was present in 65 patients (91.5%) at the first CMR (CMR-1). In all, LGE extent was significantly increased (p<0.001). A difference in %LGE between the two CMR scans was correlated with the initial %LGE (r=0.44, p<0.001). LGE progression, defined as >4% increase in LGE at the second CMR, was present in 19 patients with non-apical HCM (36.5%), but in only one apical HCM (5.3%). Also, LGE progression rate was significantly higher in non-apical (0.15%/month) versus apical HCM (0.025%/month) (p=0.001). On the multivariate model #1 including only clinical variables (age, history of paroxysmal atrial fibrillation, LV outflow tract obstruction on echocardiography, beta-blocker use, family history of sudden death, family history of HCM, syncope, non-sustained ventricular tachycardia, rate pressure product, and HCM phenotype), only apical HCM phenotype was associated with less LGE progression (p=0.038). On the multivariate model #2 including CMR variables additional to the model #1, %LGE at CMR-1 was the only determinant for LGE progression (p=0.007). When the analysis was limited to patients with preserved EF, results remained unchanged.
  
  
  CONCLUSIONS
  Myocardial fibrosis in HCM is a progressive phenomenon. Non-apical phenotype and a higher LGE extent at CMR-1 are both associated with greater LGE progression.
authors.affiliation: Department of Internal Medicine, Cardiovascular Center, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Hong-Mi
authors.initials: HM
authors.lastname: Choi
authors.affiliation: Department of Internal Medicine, Division of Cardiology, Sejong General Hospital.
authors.forename: Kyung-Hee
authors.initials: KH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Cardiovascular Center, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Joo Myung
authors.initials: JM
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Cardiovascular Center, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Yeonyee E
authors.initials: YE
authors.lastname: Yoon
authors.affiliation: Department of Internal Medicine, Cardiovascular Center, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Seung-Pyo
authors.initials: SP
authors.lastname: Lee
authors.affiliation: Department of Radiology, Cardiovascular Section, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Eun-Ah
authors.initials: EA
authors.lastname: Park
authors.affiliation: Department of Radiology, Cardiovascular Section, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Whal
authors.initials: W
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Cardiovascular Center, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Yong-Jin
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Cardiovascular Center, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Goo-Yeong
authors.initials: GY
authors.lastname: Cho
authors.affiliation: Department of Internal Medicine, Cardiovascular Center, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Dae-Won
authors.initials: DW
authors.lastname: Sohn
authors.affiliation: Department of Internal Medicine, Cardiovascular Center, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
authors.forename: Hyung-Kwan
authors.initials: HK
authors.lastname: Kim
mesh_terms: D002312:Cardiomyopathy, Hypertrophic / Q000473:pathology*; D015331:Cohort Studies; D003287:Contrast Media; D018450:Disease Progression; D005260:Female; D005355:Fibrosis / Q000473:pathology; D019786:Gadolinium DTPA; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000473:pathology; D018810:Magnetic Resonance Angiography; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology*; D018487:Ventricular Dysfunction, Left / Q000473:pathology
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA