CARDIOVASCULAR JOURNAL OF AFRICA • Vol 24, No 5, June 2013
168
AFRICA
adjusting for age, gender, time from symptom to reperfusion,
troponin I level, CK-MB level, LVEF, E/E
′
and WMSI, acute-
and early-phase BNP were identified as independent predictors
of PMIR at the six-month follow up.
Among the time phases, early-phase BNP was a meaningful
predictor of LV remodelling. ROC curves for early-phase plasma
BNP levels for the prediction of PMIR are shown in Fig. 2. The
AUC of early-phase BNP levels for predicting PMIR was 0.83
with a cut-off value of 172.9 pg/ml. Early-phase plasma BNP
levels showed a sensitivity of 76.2% and a specificity of 74.2%.
TABLE 3. BASELINEAND FOLLOW-UP
ECHOCARDIOGRAPHIC CHARACTERISTICS BETWEEN
NON-REMODELLINGAND REMODELLING GROUPS
Variable
Non-remodelling
group (
n
=
89)
Remodelling
group (
n
=
42)
p
Haemodynamics
Baseline
LVESV (ml)
31.6
±
16.8
37.2
±
19.2
0.03
LVEDV (ml)
71.1
±
20.2
74.4
±
16.1
0.36
LVEF (%)
57.0
±
9.5
50.3
±
9.3
0.00
DT (ms)
211.7
±
42.7
203.9
±
46.1
0.10
E/E
′
11.0
±
4.3
14.5
±
2.8
<
0.01
Follow up
LVESV (ml)
28.9
±
14.2
49.3
±
17.3
<
0.01
LVEDV (ml)
69.9
±
19.3
94.7
±
21.4
<
0.01
LVEF (%)
60.2
±
10.6
48.9
±
10.7
<
0.01
DT (ms)
236.7
±
42.0
204.7
±
49.3
<
0.01
E/E
′
7.9
±
3.8
11.2
±
6.2
<
0.01
Diastolic dysfunction (%)
Baseline
Grade 1 (%)
56 (62.9)
21 (50.0)
0.16
Grade 2 (%)
22 (24.7)
17 (40.5)
0.07
Grade 3 (%)
0 (0)
2 (4.8)
0.04
Follow up
Grade 1 (%)
76 (85.4)
26 (61.9)
<
0.01
Grade 2 (%)
3 (3.4)
9 (21.4)
<
0.01
Grade 3 (%)
0 (0)
5 (11.9)
<
0.01
Data are mean
±
SD or numbers (percentage).
LV, left ventricular; ESV, end-systolic volume; EDV, end-diastolic volume;
EF, ejection fraction; DT, deceleration time.
Fig. 2. From the ROC curve, the diagnostic accuracy
of the early-phase plasma BNP level for predicting LV
remodelling in patients with STEMI was 83.2% (sensitiv-
ity 76.2%; specificity 74.2%), and the optimum cut-off
point was 172.9 pg/ml (
p
<
0.01). ROC, receiver operator
characteristic; BNP, B-type natriuretic peptide; AUC, area
under the curve.
1.0
0.8
0.6
0.4
0.2
0.0
0.0
0.2
0.4
0.6
0.8
1.0
Sensitivity
1 – Specificity
Plasma BNP
=
172.9 pg/ml
AUC: 83.2%.
p
<
0.001
Fig. 1. Serial changes in plasma log BNP levels according
to left ventricular remodelling. *
p
<
0.01 for the compari-
son of plasma log BNP levels between groups.
†
p
<
0.01
for inter- and intra-group differences during the study
period. BNP, B-type natriuretic peptide; NRG, non-remod-
elling group; RG, remodelling group. Data are mean
±
SD.
2.50
2.25
2.00
1.75
1.50
1.25
1.00
Acute
Early Late Long-
term
n
=
89
n
=
89
n
=
78
n
=
69
n
=
42
n
=
42
n
=
38
n
=
33
Acute
Early Late Long-
term
Log BNP
NRG
†
RG
†
1.29
±
0.53*
1.77
±
0.67*
1.56
±
0.55*
2.31
±
0.54*
1.31
±
0.33
1.92
±
0.57
1.37
±
0.46*
2.07
±
0.55*
TABLE 4. MULTIPLE LOGISTIC REGRESSIONANALYSIS TO
EVALUATE THE TIME POINT OF PLASMA BNP SAMPLINGTHAT
IS CLOSELYASSOCIATEDWITH LV REMODELLING. STEPWISE
ADJUSTMENT OF DIFFERENT FACTORS INCLUDINGAGE,
GENDER, TIME FROM SYMPTOM ONSET TO REPERFUSION,
CK-MB LEVEL, TROPONIN-I LEVEL, E/E
′
ANDWMSI
Variable
Odds
ratio
95% Confidence
interval
p
Model 1
Age, gender adjusted
Acute BNP
1.006 1.001–1.011 0.02
Early BNP
1.011 1.007–1.016
<
0.01
Late BNP
1.005 0.998–1.011 0.15
Long-term BNP
1.010 1.004–1.016 0.01
Model 2
Time from symptom onset to
reperfusion adjustment
Acute BNP
1.005 0.999–1.010 0.08
Early BNP
1.011 1.006–1.016
<
0.01
Late BNP
1.004 0.997–1.010 0.24
Long-term BNP
1.009 1.002–1.015 0.01
Model 3
Tn-I, CK-MB adjusted
Acute BNP
1.008 1.002–1.014 0.01
Early BNP
1.012 1.006–1.018
<
0.01
Late BNP
1.004 0.997–1.012 0.22
Long-term BNP
1.007 1.001–1.014 0.03
Model 4
LVEF-, E/E
′
-, WMSI-adjusted
Acute BNP
1.007 1.001–1.014 0.02
Early BNP
1.013 1.006–1.019
<
0.01
Late BNP
1.004 0.996–1.012 0.36
Long-term BNP
1.005 0.998–1.012 0.13
*
p
-values are based on the multiple regression analysis. BNP, B-type
natriuretic peptide; Tn-I, troponin I; CK-MB, creatinine kinase myocardial
band; LVEF, left ventricular ejection fraction.
