A clinical risk score of myocardial fibrosis predicts adverse outcomes in aortic stenosis.
OBJECTIVE
Midwall myocardial fibrosis on cardiovascular magnetic resonance (CMR) is a marker of early ventricular decompensation and adverse outcomes in aortic stenosis (AS). We aimed to develop and validate a novel clinical score using variables associated with midwall fibrosis.


RESULTS
One hundred forty-seven patients (peak aortic velocity (Vmax) 3.9 [3.2,4.4] m/s) underwent CMR to determine midwall fibrosis (CMR cohort). Routine clinical variables that demonstrated significant association with midwall fibrosis were included in a multivariate logistic score. We validated the prognostic value of the score in two separate outcome cohorts of asymptomatic patients (internal: n = 127, follow-up 10.3 [5.7,11.2] years; external: n = 289, follow-up 2.6 [1.6,4.5] years). Primary outcome was a composite of AS-related events (cardiovascular death, heart failure, and new angina, dyspnoea, or syncope). The final score consisted of age, sex, Vmax, high-sensitivity troponin I concentration, and electrocardiographic strain pattern [c-statistic 0.85 (95% confidence interval 0.78-0.91), P < 0.001; Hosmer-Lemeshow χ(2) = 7.33, P = 0.50]. Patients in the outcome cohorts were classified according to the sensitivity and specificity of this score (both at 98%): low risk (probability score <7%), intermediate risk (7-57%), and high risk (>57%). In the internal outcome cohort, AS-related event rates were >10-fold higher in high-risk patients compared with those at low risk (23.9 vs. 2.1 events/100 patient-years, respectively; log rank P < 0.001). Similar findings were observed in the external outcome cohort (31.6 vs. 4.6 events/100 patient-years, respectively; log rank P < 0.001).


CONCLUSIONS
We propose a clinical score that predicts adverse outcomes in asymptomatic AS patients and potentially identifies high-risk patients who may benefit from early valve replacement.
British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK National Heart Center Singapore, Singapore, Singapore cchin03m@gmail.com.
Calvin W L
CW
Chin
Cardiology Department, AP-HP, Bichat Hospital, Paris, France.
David
D
Messika-Zeitoun
British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK.
Anoop S V
AS
Shah
Biochemistry Department, AP-HP, Tenon Hospital, Paris, France.
Guillaume
G
Lefevre
Biochemistry Department, AP-HP, Tenon Hospital, Paris, France.
Sophie
S
Bailleul
British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK.
Emily N W
EN
Yeung
British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK.
Maria
M
Koo
British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK.
Saeed
S
Mirsadraee
Cardiology Department, AP-HP, Bichat Hospital, Paris, France.
Tiffany
T
Mathieu
British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK.
Scott I
SI
Semple
British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK.
Nicholas L
NL
Mills
Cardiology Department, AP-HP, Bichat Hospital, Paris, France.
Alec
A
Vahanian
British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK.
David E
DE
Newby
British Heart Foundation/University Centre for Cardiovascular Science, University of Edinburgh, Chancellor's Building, 49 Little France Crescent, Edinburgh EH16 4SB, UK.
Marc R
MR
Dweck
D000368:Aged; D001024:Aortic Valve Stenosis / Q000401:mortality / Q000473:pathology*; D005260:Female; D005355:Fibrosis; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D009206:Myocardium / Q000473:pathology*; D011379:Prognosis; D018570:Risk Assessment / Q000379:methods; D016019:Survival Analysis
Aortic stenosis; Cardiovascular magnetic resonance imaging; Electrocardiogram strain; High-sensitivity troponin I concentrations; Midwall myocardial fibrosis