Prognostic significance of myocardial fibrosis in hypertrophic cardiomyopathy.
OBJECTIVE
We investigated the significance of fibrosis detected by late gadolinium enhancement cardiovascular magnetic resonance for the prediction of major clinical events in hypertrophic cardiomyopathy (HCM).


BACKGROUND
The role of myocardial fibrosis in the prediction of sudden death and heart failure in HCM is unclear with a lack of prospective data.


METHODS
We assessed the presence and amount of myocardial fibrosis in HCM patients and prospectively followed them for the development of morbidity and mortality in patients over 3.1 +/- 1.7 years.


RESULTS
Of 217 consecutive HCM patients, 136 (63%) showed fibrosis. Thirty-four of the 136 patients (25%) in the fibrosis group but only 6 of 81 (7.4%) patients without fibrosis reached the combined primary end point of cardiovascular death, unplanned cardiovascular admission, sustained ventricular tachycardia or ventricular fibrillation, or appropriate implantable cardioverter-defibrillator discharge (hazard ratio [HR]: 3.4, p = 0.006). In the fibrosis group, overall risk increased with the extent of fibrosis (HR: 1.18/5% increase, p = 0.008). The risk of unplanned heart failure admissions, deterioration to New York Heart Association functional class III or IV, or heart failure-related death was greater in the fibrosis group (HR: 2.5, p = 0.021), and this risk increased as the extent of fibrosis increased (HR: 1.16/5% increase, p = 0.017). All relationships remained significant after multivariate analysis. The extent of fibrosis and nonsustained ventricular tachycardia were univariate predictors for arrhythmic end points (sustained ventricular tachycardia or ventricular fibrillation, appropriate implantable cardioverter-defibrillator discharge, sudden cardiac death) (HR: 1.30, p = 0.014). Nonsustained ventricular tachycardia remained an independent predictor of arrhythmic end points after multivariate analysis, but the extent of fibrosis did not.


CONCLUSIONS
In patients with HCM, myocardial fibrosis as measured by late gadolinium enhancement cardiovascular magnetic resonance is an independent predictor of adverse outcome. (The Prognostic Significance of Fibrosis Detection in Cardiomyopathy; NCT00930735).
O'Hanlon
Rory
R
Department of Cardiovascular Magnetic Resonance, Royal Brompton and Harefield NHS Foundation Trust, London, UK.
Grasso
Agata
A
Roughton
Michael
M
Moon
James C
JC
Clark
Susan
S
Wage
Ricardo
R
Webb
Jessica
J
Kulkarni
Meghana
M
Dawson
Dana
D
Sulaibeekh
Leena
L
Chandrasekaran
Badri
B
Bucciarelli-Ducci
Chiara
C
Pasquale
Ferdinando
F
Cowie
Martin R
MR
McKenna
William J
WJ
Sheppard
Mary N
MN
Elliott
Perry M
PM
Pennell
Dudley J
DJ
Prasad
Sanjay K
SK
D000328:Adult; D000368:Aged; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications* / Q000473:pathology*; D003645:Death, Sudden / Q000209:etiology*; D005260:Female; D005355:Fibrosis; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology*; D011379:Prognosis