CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 4, May 2013
132
AFRICA
Where very high blood pressure values were not adequately
controlled, combination antihypertensive therapy using
intravenous hydralazine or labetolol with the addition of
magnesium sulphate was used.
Laboratory analysis (Table 2) showed lower platelet counts in
the pre-eclamptic group; 10 patients in the pre-eclamptic group
developed thrombocytopaenia and one in the normotensive
pregnancies. As expected, serum creatinine, urea, uric acid
and urine protein levels were significantly elevated in the
pre-eclamptic group. There were no differences in gestational
age and estimated foetal weight between groups. Polyhydraminos
was present in one normotensive patient and in six pre-eclamptic
patients. The umbilical artery resistance index was significantly
higher in the pre-eclamptic group compared to the normotensive
group (0.68
±
0.06 vs 0.63
±
0.05;
p
<
0.0001).
Echocardiographic and BNP findings are shown in Table
3. There were no differences in the left ventricular chamber
dimensions and ejection fraction between the two groups. The
left atrium diameter was slightly increased in the pre-eclamptic
group but this difference was not significant. Estimates of the
left ventricular filling pressure as measured by tissue Doppler
E/E
a
ratio were significantly higher in the pre-eclamptic group
compared to the normotensive pregnancies (11.02
±
5.6 vs 9.16
±
2.6;
p
<
0.05).
There were significant differences between the NT-proBNP
levels in all pre-specified time points between the PE and
normotensive controls except post delivery (Fig. 1). NT-proBNP
levels were significantly increased in the antepartum period in
the pre-eclamptic group compared to the normotensive group
[(2–184.1) vs 6.0 (0.5–45.2) pmol/l;
p
<
0.0001]. BNP levels
rose during labour (1.8–206.4 vs 1.9–24.8 pmol/l;
p
<
0.01)
and subsided in the postpartum period (1.7–51.4 vs 2.2–38.7
pmol/l;
p
<
0.01). There was a weak positive correlation between
baseline NT-proBNP and TD (
r
=
0.22;
p
<
0.051), and a stronger
correlation between baseline NT-proBNP and the resistance
index (
r
=
0.321;
p
<
0.001).
The number of maternal complications was higher in the
pre-eclamptic group compared to the normotensive group (Table
4). In the normotensive group, 38 patients delivered vaginally
and 18 were delivered by Caesarean section (CS), while in the
pre-eclamptic group, 24 were delivered by CS and 27 delivered
by the vaginal route. The CS rate was significantly higher in the
pre-eclamptic group (24 vs 18;
p
<
0.05).
Among the normotensive group, most indications (8/14) were
for foetal distress and cephalopelvic disproportion. Among the
pre-eclamptic group severe pre-eclampsia/eclampsia and foetal
distress accounted for most (17/19) indications for CS. After
delivery, two PE patients were admitted to an intensive care unit
and five required high-care nursing.
As expected, the birthweight was significantly lower in
the pre-eclamptic pregnancies compared to the normotensives
TABLE 1. DEMOGRAPHIC DATA BETWEEN GROUPS
Parameter
Normotensive
(
n
=
63)
Pre-eclamptic
(
n
=
52)
p
-value
Age (years)
20.4
±
3.7 21.5
±
4.7
<
0.06
BMI (kg/m
2
)
27.9
±
5.5 29.4
±
7.9
<
0.05
Gestational age at entry (weeks)
34.5
±
2.7 34.3
±
2.7
ns
Gestational age at delivery (weeks) 38.4
±
1.9 37.8
±
2.2
ns
Urine dipstick
0 (0–1
+
)
2
+
(1
+
–3
+
)
<
0.0001
Oedema
0 (0–1
+
)
2
+
(1
+
–4
+
)
<
0.0001
HIV status positive
17
17
CD
4
count
<
200 (cells/mm)
5
5
SBP (mmHg)
127.03
±
12.9 163.2
±
17.6
<
0.0001
DBP (mmHg)
78.32
±
8.6 104.4
±
11.9
<
0.0001
Pulse (bpm)
84.7 (72–96) 86.0 (72–106)
<
0.04
Values are expressed as mean
±
standard deviation. Actual counts are reported
for HIV status and CD4 count. SBP
=
systolic blood pressure; DBP
=
diastolic
blood pressure; bpm
=
beats per minute.
TABLE 2. BASELINE CHARACTERISTICS
Parameter
Normotensive
(
n
=
63)
Preeclamptic
(
n
=
52)
p
-value
Full blood count
Hemoglobin (g/dl)
10.9
±
1.3
11.3
±
1.4
ns
Platelets (
×
10
9
/l)
251.8
±
82.8
33.1
±
3.1
215.5
±
82.6
<
0.02
Haematocrit (l/l)
34.2
±
3.6
<
0.07
Blood chemistry
2.5
±
0. 7
Urea (mmol/l)
54.5
±
8.9
3.08
±
1.18
<
0.002
Creatinine (
µ
mol/l)
0.27
±
0.06
62.4
±
12.7
<
0.0001
Uric acid (mmol/l)
0.33
±
0.07
<
0.0001
Urine dipstick
0 (0–1
+
)
Proteinuria
2
+
(1
+
–3
+
)
<
0.0001
Resistance index
0.63 (0.5–0.62) 0.68 (0.62–0.84
<
0.0001
Gestational age
34 (28–39)
34 (26–39)
ns
Estimated foetal weight
2.6 (1.2–3.7)
2.5 (0.8–3.8)
ns
Adequate liquor
60
42
ns
TABLE 3. ECHOCARDIOGRAPHICAND BNP FINDINGS
WITHIN GROUPS
Parameter
Normal
range
Normotensive
(
n
=
41)
Pre-eclamptic
(
n
=
36)
p
-value
LV diastole (mm)
35–55 49 (37–56)
50 (39–60)
ns
LV systole (mm)
23–34 33 (23–40)
34 (24–41)
ns
Fractional shortening (%) 27–35 32 (27–42)
32 (26–38)
ns
Ejection fraction (%)
30–60 64 (54–62)
64 (56–66)
ns
LV posterior wall (mm)
6–10
7 (5–9)
7 (5–10)
ns
Septal thickness (mm)
6–10
7 (5–9)
7 (4–10)
ns
Left atrium (mm)
19–39 35 (25–41)
38 (32–55)
ns
Aortic root (mm)
20–37 23 (21–29)
24 (19–30)
ns
Tissue Doppler (E
a
)
<
8 9.2 (4.5–12.25) 11.0 (7.3–15.4)
<
0.05
BNP (median) (pg/mol)
Antepartum (1)
6.0 (0.5–45.2) 23.8 (2–184.1)
<
0.0001
Labour (2)
8.7 (1.9–24.8) 15.0 (1.8–206.4)
<
0.01
Postpartum (3)
5.95 (2.2–38.7) 4.2 (1.7–51.4)
<
0.01
Median values for all parameters with range in brackets
Fig 1. Median BNP level by pre-eclampsia and time point.
25.000
20.000
15.000
10.000
5.000
0.000
1
2
3
Normotensive
Pre-eclamptic
