Effect of Left Ventricular Outflow Tract Obstruction on Left Atrial Mechanics in Hypertrophic Cardiomyopathy
Table 3
Baseline clinical, CMR, and 2D echocardiographic parameters in the nonobstructive and obstructive HCM subgroups.
Nonobstructive HCM ()
Obstructive HCM ()
value
Clinical characteristics
Age at CMR (years)
44.7 ± 15
54.6 ± 12
0.001
Sex (male, , %)
36 (72)
34 (68)
0.83
BSA
1.92 ± 0.2
1.96 ± 0.2
0.35
NYHA I/II/III/IV (%)
82/14/4/0
32/22/46/0
<0.0001
Atrial fibrillation (, %)
3 (6)
4 (8)
0.69
Beta-blockers (, %)
22 (44)
42 (84)
0.0001
Calcium channel blockers (, %)
5 (10)
4 (8)
0.73
Disopyramide (, %)
0 (0)
38 (76)
<0.0001
ACE-i/ARB (, %)
7 (14)
6 (12)
0.77
Amiodarone (, %)
2 (4)
1 (2)
0.56
Coumadin (, %)
4 (8)
2 (4)
0.40
CMR parameters
LVEF (%)
61.7 ± 6
64.6 ± 7
0.03
LVEDVi (mL/m2)
86.1 ± 15
87.5 ± 12
0.62
LVMi (g/m2)
73.0 ± 26
87.7 ± 24
0.006
2D echocardiographic parameters
LVOT resting (mmHg)
6.6 ± 2
56.2 ± 28
<0.0001
LVOT provocable (mmHg)
12.1 ± 7
82.7 ± 30
<0.0001
Maximal wall thickness (mm)
19.1 ± 5
20.7 ± 4
0.002
MR: trivial/mild/moderate/severe (%)
74/26/0/0
18/46/28/8
<0.0001
wave (m/sec)
0.68 ± 0.2
0.86 ± 0.2
<0.001
wave (m/sec)
0.49 ± 0.2
0.73 ± 0.2
<0.001
ratio
1.54 ± 0.6
1.32 ± 0.6
0.07
Deceleration time (ms)
217 ± 48
264 ± 62
<0.001
Isovolumic relaxation time (ms)
89 ± 17
94 ± 23
0.32
ratio
7.2 ± 3
11.2 ± 5
<0.0001
CMR: cardiac magnetic resonance; BSA: body surface area; NYHA: New York Heart Association functional class; LVEF: left ventricular ejection fraction; LVEDVi: indexed left ventricular end-diastolic volume; LVMi: indexed left ventricular mass; LVOT: left ventricular outflow tract gradient; MR: mitral regurgitation.
