Table 4

Characteristics of Patients Stratified According to iECV Thresholds and Presence of Mid-Wall Late Gadolinium Enhancement

Normal Myocardium (n = 71)Extracellular Expansion (n = 31)Replacement Fibrosis (n = 37)p Value
Age, yrs70 (63−75)70 (63−75)71 (65−78)0.59
Sex (male = 1)0.56 (0.44−0.68)0.81 (0.67−0.96)0.76 (0.62−0.90)0.023
Hypertension48 (68)20 (65)22 (59)0.70
Diabetes8 (11)7 (23)2 (5)0.09
Body mass index, kg/m228.2 ± 4.528.9 ± 4.629.3 ± 4.30.44
Echocardiography
 Peak aortic jet velocity, m/s3.53 ± 0.823.79 ± 1.04.23 ± 0.92<0.001
 Aortic valve area, cm20.98 (0.73−1.18)0.88 (1.2−0.7)0.83 (0.73−0.91)0.049
 Mean AV pressure gradient, mm Hg29.1 ± 14.234.8 ± 21.141.1 ± 23.50.007
  Mild AS2472
  Moderate AS181011
  Severe AS291424
 Valvulo-arterial impedance, mm Hg/ml/m24.1 ± 1.03.9 ± 0.94.0 ± 1.00.46
 Mean e', cm/s6.7 ± 2.06.5 ± 1.85.2 ± 1.40.0004
 Mean E/e' ratio13.1 ± 7.713.2 ± 4.816.5 ± 6.50.04
 Mean diastolic dysfunction grade1.5 ± 0.92.0 ± 0.92.7 ± 0.5<0.0001
CMR
 LVMi, g/m273 ± 1196 ± 11107 ± 25<0.0001
 Relative wall thickness0.60 ± 0.120.61 ± 0.090.67 ± 0.110.018
 ECVi, ml/m218.3 ± 2.525.4 ± 3.130.4 ± 8.2<0.0001
 Ejection fraction, %68 (63−71)66 (64−71)67 (64−72)0.94
 Longitudinal systolic function, mm13.2 ± 2.612.5 ± 2.411.2 ± 3.10.002
 Indexed left atrial volume, ml/m231 ± 1337 ± 1138 ± 150.027
Biomarkers
 Natural log (hs troponin I)1.43 ± 0.962.02 ± 0.932.60 ± 0.90<0.0001
 Natural log (BNP)2.95 ± 1.003.06 ± 0.963.41 ± 1.100.12
Functional status
 6-min walk test, m406 ± 74385±95359 ± 1380.08
 NYHA functional class
  I33 (46)18 (58)17 (46)
  II27 (38)6 (19)12 (32)
  III11 (15)7 (23)5 (14)
  IV0 (0)0 (0)3 (8)
Outcomes
 All-cause mortality248
 All-cause mortality rate (per 1,000 patient-yrs)836710.009
 AS-related mortality, n046
 AS-related mortality rate (per 1,000 patient-yrs)036520.0045
Patients Undergoing Myocardial BiopsyNormal Myocardium on CMR (n = 3)Extracellular Expansion on CMR (n = 5)Replacement Fibrosis on CMR (n = 3)p Value
Histological fibrosis, %8.9 ± 4.012.4 ± 2.522.4 ± 4.90.004
Aortic valve area, cm20.57 ± 0.100.94 ± 0.290.81 ± 0.440.29
Peak aortic jet velocity, m/s4.6 (4.4−5.1)4.5 (4.0−5.9)4.9 (4.1−8.0)0.63
LVMi, g/m276 ± 1598 ± 4162 ± 6<0.0001
Native myocardial T1, ms1,189 ± 231,183 ± 161,277 ± 150.0002
Post-contrast myocardial T1, ms676 ± 45615 ± 24672 ± 840.22
Partition coefficient0.43 ± 0.050.47 ± 0.020.55 ± 0.020.008
ECV fraction, %25.3 ± 3.127.3 ± 1.432.2 ± 1.90.019
iECV, ml/m218.8 ± 1.925.6 ± 0.749.6 ± 4.8<0.0001

Values are median (interquartile range), n (%), or mean ± SD.

Abbreviations as in Tables 1, 2, and 3.