Dyssynchrony Assessment with Tissue Doppler Imaging and Regional Volumetric Analysis by 3D Echocardiography Do Not Predict Long-Term Response to Cardiac Resynchronization Therapy
Table 1
Baseline characteristics and echocardiographic parameters pre-CRT and after long-term CRT.
Characteristic
Baseline
After CRT (6 m)
P-value
Age (years)
59.9 ± 12.5
Gender: males
67%
Etiology: dilated cardiomyopathy
79%
QRS duration (ms)
161.2 ± 16.9
Clinical parameters:
NYHA class (1/2/3/4)
0/7/23/3
9/17/5/2
<.0005
MNLWHF score
49.7 ± 22.4
30.4 ± 22.9
<.0005
6-minute walk distance (meters)
428 ± 69
482 ± 91
<.0005
Echocardiographic parameters:
LV end-diastolic volume (mL)
245.3 ± 128.5
192.5 ± 101.3
.006
LV end-systolic volume (mL)
188.9 ± 109.1
125.8 ± 80.3
.0002
LV ejection fraction (%)
25 ± 6
38 ± 11
.0001
LV end-diastolic diameter (cm)
6.9 ± 1.5
6.3 ± 1.5
.004
LV end-systolic diameter (cm)
6.0 ± 1.5
5.1 ± 1.6
.0008
LV fractional shortening (%)
13.3 ± 0.5
19 ± 0.9
.006
Mitral regurgitation
1.67 ± 1.1
1.32 ± 0.8
.03
TDI: SD of Tf-Ts in 12 segments (ms)
44.2 ± 14.1
34.1 ± 14.4
.0008
TDI: SD of Tf-Ts in 6 basal segments (ms)
106.3 ± 41.7
76.5 ± 35.8
.0001
TDI: SD of septal-to-lateral delay (ms)
58.1 ± 37.1
61.2 ± 36.8
.32
3D: SD of Tmsv in 6 basal segments (ms)
84.6 ± 56.4
53.9 ± 41.3
.01
3D: SD of Tmsv in 12 segments (ms)
46.3 ± 31.1
24.4 ± 20.5
.002
3D: SD of Tmsv in 16 segments (ms)
58.1 ± 35.2
35 ± 28.8
.04
3D: SD of Tmsv in 12 segments as % of R-R interval
5.8 ± 4.2%
3.1 ± 2.9%
.0004
3D: SD of Tmsv in 16 segments as % of R-R interval
7.0 ± 4.1%
4.3 ± 3.8%
.01
CRT: cardiac resynchronization therapy, LV: left ventricle, TDI: tissue Doppler imaging, Tf-Ts: difference in time to peak systolic velocity between the fastest and slowest LV segments, Tmsv: difference in longest and shortest time to minimal systolic volume in LV segments, NYHA: New York Heart Association, MNHFQ: Minnesota Living with Heart Failure questionnaire, SD: standard deviation.
