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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 31, No 3, May/June 2020
126
AFRICA
Comparison of TDI parameters measured from the lateral
mitral annulus (m) demonstrated similar S
′
, E
′
and A
′
velocities;
E/E
′
ratios; ejection time and isovolumetric contraction time;
isovolumetric relaxation time; and myocardial performance
index among the three groups (Table 3). The treatment groups
(IVA and LPC) had significantly higher ejection time and
isovolumetric relaxation time, and lower E
′
velocity, measured at
the septal part of the mitral annulus, than the control group (
p
< 0.001), whereas S
′
and A
′
velocity, isovolumetric contraction
time and MPI were similar. In addition, A
′
velocity derived
from the lateral tricuspid annulus was significantly higher in the
treatment groups than in the control group (
p
= 0.007), whereas
S
′
and E
′
velocity, ejection time, isovolumetric contraction time,
isovolumetric relaxation time and MPI were similar. On the
other hand, A
′
velocity measured from the lateral tricuspid
annulus was not significantly different between the IVA and
LPC groups.
DI and strain values were significantly lower in the treatment
groups (LPC and IVA) than in the control group (
p
< 0.05) (Table
4, Fig. 2). SI values were significantly higher in comparison with
the control group (
p
< 0.05) (Table 4). There was no statistically
significant difference in aortic elastic parameters between the
LPC and IVA groups.
Intra-observer reproducibility of aortic measurements was
calculated after the re-evaluation of randomly selected images of
31 patients and 20 controls, and the results were 2.2 and 2.6%,
respectively, for AoD, 3.1 and 3.4%, respectively, for AoS, 2.2 and
2.6%, respectively, for DI, and 3.4 and 3.1%, respectively, for SI.
Table 1. Clinical features of the study groups
Demographic
features
LPC group
(
n
= 15)
IVA group
(
n
= 16)
Control
(
n
= 20)
p
-value
Age (months)
17 ± 4.4
14.4 ± 4.9
14.5 ± 2.8
0.257
Gender (
n
, %)
Male
4 (26.7)
9 (56.3)
8 (40)
0.245
Female
11 (73.3)
7 (43.8)
12 (60)
Weight (kg)
10.1 ± 1.4
9.6 ± 2.1
9.86 ± 0.3
0.743
Height (cm)
78.2 ± 6.1
78.1 ± 10.2
78.3 ± 0.57 0.999
GA (weeks)
29.8 ± 2.7
29.3 ± 2.9
29.5 ± 2.8
0.641
BW (g)
1464 ± 451
1279 ± 320
1352 ± 394 0.196
HR (beats/min)
127.5 ± 14.9
137.7 ± 20.8
139.8 ± 11.9 0.208
SBP (mmHg)
84 ± 9.7
(70–102)
90 ± 6.7
(80–105)
86 ± 9.0
(72–102)
0.971
DBP (mmHg)
48 ± 5.3
(41–60)
48 ± 6.1
(39–65)
49 ± 7.9
(39–63)
0.147
PMA at treat-
ment (weeks)
35.3 ± 1.66
(32–38)
35.5 ± 1.64
(32–37)
–
0.972
Time of echo
(months)
13.2 ± 2.8
12.9 ± 2.3
0.125
Data are presented as the mean values ± SD.
Student’s
t
-test, Kruskal–Wallis test:
p
< 0.05 considered statistically significant.
GA: gestational age, BW: birth weight, HR: heart rate, SBP: systolic blood pres-
sure, DBP: diastolic blood pressure, LPC: laser photocoagulation, IVA: intravit-
real aflibercept, PMA: postmenstrual age, IVI: intravitreal injection.
Table 2. M-mode echocardiographic parameters of the study groups
M-mode measurements
LPC group
(
n
= 15)
IVA group
(
n
= 16)
Control
(
n
= 20)
p
-value
IVSd (mm)
0.54 ± 0.09 0.51 ± 0.06 0.52 ± 0.04 0.656
IVSs (mm)
0.56 ± 0.09 0.6 ± 0.08 0.54 ± 0.04 0.192
LVIDd (mm)
2.58 ± 0.25 2.5 ± 0.36 2.57 ± 0.23 0.150
LVIDs (mm)
1.59 ± 0.19 1.5 ± 0.19 1.51 ± 0.13 0.249
LVPWd (mm)
0.43 ± 0.04 0.45 ± 0.06 0.43 ± 0.04 0.584
LVPWs (mm)
0.74 ± 0.08 0.78 ± 0.18 0.75 ± 0.07 0.871
EF (%)
70.9 ± 3.6 71.9 ± 4.2 72.8 ± 3.96 0.466
FS (%)
38.5 ± 3.1 39.6 ± 3.8 40.3 ± 4.1 0.535
MAPSE (cm)
10.0 ± 0.56 10.3 ± 0.99 11.1 ± 1.3 0.020*
TAPSE (cm)
17 ± 1.21 16.3 ± 2.2 16.4 ± 1.58 0.661
Data are presented as the mean values ± SD.
One-way analysis of variance (ANOVA) or Kruskal–Wallis tests: *
p
< 0.05
considered statistically significant.
IVSs: interventricular septum systolic thickness, IVSd: interventricular septum
diastolic thickness, LVIDd: left ventricular end-diastolic diameter, LVIDs: left
ventricular end-systolic diameter, LVPWd: left ventricle posterior wall diastolic
dimension, LWPWs: left ventricle posterior wall systolic dimension, EF: ejec-
tion fraction, FS: fractional shortening, MAPSE: mitral annular plane systolic
excursion, TAPSE: tricuspid annular plane systolic excursion.
Table 3. Conventional and tissue Doppler echocardiographic
parameters of the study groups
‘Pulsed’ and tissue
‘pulsed’ Doppler
measurements
Group 1
(LPC) (
n
= 15)
Group 2
(IVA) (n = 16 )
Controls
(
n
= 20) p-value
Mitral E (cm/s)
98 ± 8.2
98 ± 14
98 ± 13 0.970
Mitral A (cm/s)
69 ± 11
65 ± 12
60 ± 7.2 0.834
Mitral E/A
1.66 ± 0.31
1.65 ± 0.34
1.65 ± 0.25 0.901
Tricuspid E (cm/s)
74 ± 6.0
78 ± 10
70 ± 16 0.037*
#
Tricuspid A (cm/s)
47 ± 8.2
46 ± 11
44 ± 6.6 0.511
Tricuspid E/A
1.55 ± 0.24
1.55 ± 0.24
1.72 ± 0.41 0.428
Sm (cm/s)
7.7 ± 1.9
7.8 ± 1.47
7.4 ± 0.99 0.261
E’m (cm/s)
10.8 ± 1.3
10.4 ± 1.0
12.4 ± 1.4 0.004*
A’m (cm/s)
7.2 ± 1.3
7.2 ± 2.8
7.2 ± 1.06 0.871
ETm (ms)
213.3 ± 16.5
195.6 ± 33.0 185.4 ± 18.3 0.007*
IVCTm (ms)
48.8 ± 7.6
46.1 ± 8.5
47.7 ± 7.1 0.488
IVRTm (ms)
48.3 ± 5.42
44.6 ± 5.88
41.0 ± 4.44 0.002*
MPIm (Tei index)
0.45 ± 0.04
0.49 ± 0.08
0.47 ± 0.03 0.560
E/E
′
m
8.02 ± 2.03
8.02 ± 2.05
8 ± 1.67 0.900
Ss (cm/s)
6.7 ± 1.9
6.7 ± 1.0
7 ± 0.97 0.766
E
′
s (cm/s)
11.8 ± 4.8
9.7 ± 3.0
10.6 ± 3.8 0.182
A
′
s (cm/s)
7.2 ± 1.3
6.6 ± 1.89
7.4 ± 2.2 0.516
ETs (ms)
207.2 ± 27.2
197.3 ± 32.5 193.2 ± 25 0.061
IVCTs (ms)
47 ± 4.6
45 ± 7.6
42.5 ± 7.01 0.174
IVRTs (ms)
43.6 ± 5.4
44.6 ± 5.6
43 ± 6.0 0.236
MPIs (Tei index)
45 ± 4.3
46.1 ± 5.6
44.5 ± 6.21 0.792
E/E
′
s
9.8 ± 2.05
9.8 ± 2.05
8.8 ± 2.0 0.230
Sr (cm/s)
9 ± 4.4
9.4 ± 4.2
8.7 ± 5.3 0.755
E
′
r (cm/s)
13.1 ± 3.8
14.6 ± 2.1
14.5 ± 2.03 0.515
A
′
r (cm/s)
10.1 ± 2.0
11 ± 2.0
8.8 ± 1.0 0.007*
ETr (ms)
210.1 ± 15.8
202.1 ± 27.8 195.8 ± 27.5 0.379
IVCTr (ms)
49.2 ± 5.8
46.3 ± 10
46.8 ± 9.68 0.663
IVRTr (ms)
51.3 ± 5.9
50 ± 8.1
46.5 ± 7.9 0.211
MPIr (Tei index)
45.0 ± 4.3
46.5 ± 6
47.5 ± 5.1 0.815
E/E
′
r
6.8 ± 1.18
6.8 ± 1.18
6.88 ± 1.09 0.673
Data are presented as the mean values ± SD.
One-way analysis of variance (ANOVA) or Kruskal–Wallis tests: *
p
< 0.05
considered statistically significant,
#
p
< 0.05 (LPC vs IVA, Mann–Whitney
U
-test).
A
′
: late diastolic myocardial velocity, E
′
: early diastolic myocardial veloc-
ity, S: systolic myocardial velocity, ET: ejection time, IVCT: isovolumetric
contraction time, IVRT: isovolumetric relaxation time, MPI: myocardial perfor-
mance index, m: lateral mitral annulus, r: lateral tricuspid annulus, s: septal
mitral annulus.
Table 4. Comparison of aortic elasticity parameters of the study groups
Elasticity parameters
LPC group
(
n
= 15)
IVA group
(
n
= 16)
Control
(
n
= 20)
p
-value
Aortic strain
16.2 ± 4.4 16.7 ± 3.9 22.6 ± 4.5 0.018*
Stiffness index
3.4 ± 0.7
3.6 ± 0.6
2.2 ± 0.3 0.036*
Distensibility index
8.2 ± 1.6
8.0 ± 1.8 11.6 ± 2.4
0.025*
Data are presented as the mean values ± SD
One-way analysis of variance (ANOVA) or Kruskal–Wallis tests: *
p
< 0.05
considered statistically significant.