J Clin Med Res

Journal of Clinical Medicine Research, ISSN 1918-3003 print, 1918-3011 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Clin Med Res and Elmer Press Inc

Journal website http://www.jocmr.org

Original Article

Volume 10, Number 3, March 2018, pages 254-259

Brain Natriuretic Peptide Levels in Acute Inferior Myocardial Infarction

**Table 1.** Baseline Characteristics of Patients
Variables	Inferior MI + RVMI (n = 27)	Isolated inferior MI (n = 34)	P
BMI: body mass index; DBP: diastolic blood pressure; DM: diabetes mellitus; GFR: glomerular filtration rate; HR: heart rate; HT: hypertension; OTP: onset time of chest pain; SBP: systolic blood pressure. ^‡Independent groups t-test, ^#Mann-Whitney U test, *Pearson’s Chi-squared test, ^†Significant at p < 0.05. Data are shown in mean ± standard deviation, median or number (%).
Age, years	59.48 ± 11.46	61.06 ± 11.83	0.60^‡
Sex, F/M	9/18	10/24	0.74*
BMI, kg/m²	27.47 ± 4.28	25.57 ± 4.28	0.86^‡
DM, n, %	6, 22.2	3, 8.8	0.17*
HT, n, %	11, 40.7	16, 47.1	0.62*
Smoking, n, %	15, 55.6	17, 50	0.67*
Familial history, n, %	11, 40.7	19, 55.9	0.24*
SBP, mm Hg	134.12 ± 38.25	129.28 ± 20.10	0.99^‡
DBP, mm Hg	76.25 ± 29.28 89.00	80.75 ± 11.17 80.00	0.88^#
HR, /min	74.37 ± 12.33	71.72 ± 12.92	0.36^‡
OTP, h	4.26 ± 3.03 4.00	6.59 ± 5.11 4.50	0.04^#†
GFR (mL/min)	107.10 ± 38.95 101.24	92.33 ± 37.21 87.79	0.50^#
Gensini score	32.87 ± 28.59 25.00	30.77 ± 27.24 25.00	0.91^#

Table 1. Baseline Characteristics of Patients

Variables

Inferior MI + RVMI (n = 27)

Isolated inferior MI (n = 34)

BMI: body mass index; DBP: diastolic blood pressure; DM: diabetes mellitus; GFR: glomerular filtration rate; HR: heart rate; HT: hypertension; OTP: onset time of chest pain; SBP: systolic blood pressure. ^‡Independent groups t-test, ^#Mann-Whitney U test, *Pearson’s Chi-squared test, ^†Significant at p < 0.05. Data are shown in mean ± standard deviation, median or number (%).

Age, years

59.48 ± 11.46

61.06 ± 11.83

0.60^‡

Sex, F/M

9/18

10/24

0.74*

BMI, kg/m²

27.47 ± 4.28

25.57 ± 4.28

0.86^‡

DM, n, %

6, 22.2

3, 8.8

0.17*

HT, n, %

11, 40.7

16, 47.1

0.62*

Smoking, n, %

15, 55.6

17, 50

0.67*

Familial history, n, %

11, 40.7

19, 55.9

0.24*

SBP, mm Hg

134.12 ± 38.25

129.28 ± 20.10

0.99^‡

DBP, mm Hg

76.25 ± 29.28
89.00

80.75 ± 11.17
80.00

0.88^#

HR, /min

74.37 ± 12.33

71.72 ± 12.92

0.36^‡

OTP, h

4.26 ± 3.03
4.00

6.59 ± 5.11
4.50

0.04^#†

GFR (mL/min)

107.10 ± 38.95
101.24

92.33 ± 37.21
87.79

0.50^#

Gensini score

32.87 ± 28.59
25.00

30.77 ± 27.24
25.00

0.91^#

**Table 2.** Left Ventricular Echocardiographic Parameters
Variables	Inferior MI + RVMI (n = 27)	Isolated inferior MI (n = 34)	P
DT: deceleration time; E/A ratio: ratio of early to late diastolic filling; E/E’: ratio of early filling velocity to tissue Doppler early filling velocity; ET: ejection time; IVCT: isovolumetric contraction time; IVRT: isovolumetric relaxation time; LA: left atrium; LVEDD: left ventricular end-diastolic diameter; LVEF: left ventricular ejection fraction; LVESD: left ventricular end-systolic diameter; RVMI: right ventricular myocardial infarction. ^‡Independent groups t-test. ^#Mann-Whitney U test. Data are shown in mean ± standard deviation, and median.
LA, mm	38.92 ± 3.99	40.31 ± 4.28	0.46^‡
LVEDD, mm	50.50 ± 4.54 50.50	50.59 ± 3.56 51.00	0.81^#
LVESD, mm	35.12 ± 4.70	34.78 ± 3.82	0.43^‡
LVEF, %	57.62 ± 7.05	57.50 ± 6.71	0.38^‡
Mitral E wave, cm/s	0.80 ± 0.20	0.73 ± 0.24	0.47^‡
Mitral A wave, cm/s	0.75 ± 0.24	0.77 ± 0.17	0.66^‡
DT, ms	218.71 ± 60.64 205.50	217.00 ± 62.63 217.00	0.65^#
E/A ratio	1.26 ± 0.79 1.00	1.02 ± 0.44 0.86	0.33^#
E/E’ ratio	12.55 ± 6.2	9.68 ± 3.14	0.05^‡
Lateral Sm, cm/s	7.71 ± 1.83 7.50	7.28 ± 1.99 7.50	0.77^#
Lateral IVCT, ms	66.71 ± 16.60	66.12 ± 17.44	0.54^‡
Lateral IVRT, ms	77.79 ± 16.13	74.06 ± 16.04	0.54^‡
Lateral ET, ms	264.87 ± 19.52 265.50	262.59 ± 40.03 264.00	0.99^#

Table 2. Left Ventricular Echocardiographic Parameters

Variables

Inferior MI + RVMI (n = 27)

Isolated inferior MI (n = 34)

DT: deceleration time; E/A ratio: ratio of early to late diastolic filling; E/E’: ratio of early filling velocity to tissue Doppler early filling velocity; ET: ejection time; IVCT: isovolumetric contraction time; IVRT: isovolumetric relaxation time; LA: left atrium; LVEDD: left ventricular end-diastolic diameter; LVEF: left ventricular ejection fraction; LVESD: left ventricular end-systolic diameter; RVMI: right ventricular myocardial infarction. ^‡Independent groups t-test. ^#Mann-Whitney U test. Data are shown in mean ± standard deviation, and median.

LA, mm

38.92 ± 3.99

40.31 ± 4.28

0.46^‡

LVEDD, mm

50.50 ± 4.54
50.50

50.59 ± 3.56
51.00

0.81^#

LVESD, mm

35.12 ± 4.70

34.78 ± 3.82

0.43^‡

LVEF, %

57.62 ± 7.05

57.50 ± 6.71

0.38^‡

Mitral E wave, cm/s

0.80 ± 0.20

0.73 ± 0.24

0.47^‡

Mitral A wave, cm/s

0.75 ± 0.24

0.77 ± 0.17

0.66^‡

DT, ms

218.71 ± 60.64
205.50

217.00 ± 62.63
217.00

0.65^#

E/A ratio

1.26 ± 0.79
1.00

1.02 ± 0.44
0.86

0.33^#

E/E’ ratio

12.55 ± 6.2

9.68 ± 3.14

0.05^‡

Lateral Sm, cm/s

7.71 ± 1.83
7.50

7.28 ± 1.99
7.50

0.77^#

Lateral IVCT, ms

66.71 ± 16.60

66.12 ± 17.44

0.54^‡

Lateral IVRT, ms

77.79 ± 16.13

74.06 ± 16.04

0.54^‡

Lateral ET, ms

264.87 ± 19.52
265.50

262.59 ± 40.03
264.00

0.99^#

**Table 3.** Right Ventricular Echocardiographic Parameters
Variables	Inferior MI + RVMI (n = 27)	Isolated inferior MI (n = 34)	P
RSm: right ventricular systolic wave; RVFAC: right ventricle fractional area change; RVMI: right ventricular myocardial infarction; RVMPI: right ventricular myocardial performance index; TAPSE: tricuspid annular plane systolic excursion. ^‡Independent groups t-test. ^#Mann-Whitney U test. ^!Significant at P < 0.05. Data are shown in mean ± standard deviation, and median.
RSm, cm/s	11.00 ± 1.50 13.00	13.94 ± 2.17 12.50	0.90^#
RVMPI	0.58 ± 0.14 0.57	0.61 ± 0.16 0.57	0.62^#
TAPSE, mm	17.04 ± 1.64 19.00	21.23 ± 2.35 21.00	0.00^#!
RVFAC, %	46.37 ± 9.86	55.50 ± 7.77	0.00^‡!

Table 3. Right Ventricular Echocardiographic Parameters

Variables

Inferior MI + RVMI (n = 27)

Isolated inferior MI (n = 34)

RSm: right ventricular systolic wave; RVFAC: right ventricle fractional area change; RVMI: right ventricular myocardial infarction; RVMPI: right ventricular myocardial performance index; TAPSE: tricuspid annular plane systolic excursion. ^‡Independent groups t-test. ^#Mann-Whitney U test. ^!Significant at P < 0.05. Data are shown in mean ± standard deviation, and median.

RSm, cm/s

11.00 ± 1.50
13.00

13.94 ± 2.17
12.50

0.90^#

RVMPI

0.58 ± 0.14
0.57

0.61 ± 0.16
0.57

0.62^#

TAPSE, mm

17.04 ± 1.64
19.00

21.23 ± 2.35
21.00

0.00^#!

RVFAC, %

46.37 ± 9.86

55.50 ± 7.77

0.00^‡!

**Table 4.** Brain Natriuretic Peptide Levels
Variables	Inferior MI + RVMI (n = 27)	Isolated inferior MI (n = 34)	P
Data are shown as median ± standard deviation, and median. BNP: brain natriuretic peptide; RVMI: right ventricular myocardial infarction; TnI: troponin I. ^#Mann-Whitney U test.
BNP, pg/mL	372.92 ± 324.75 245.19	430.13 ± 320.39 281.66	0.52^#
TnI, ng/mL	1.78 ± 6.13 0.12	7.11 ± 13.21 1.38	0.01^#

Table 4. Brain Natriuretic Peptide Levels

Variables

Inferior MI + RVMI (n = 27)

Isolated inferior MI (n = 34)

Data are shown as median ± standard deviation, and median. BNP: brain natriuretic peptide; RVMI: right ventricular myocardial infarction; TnI: troponin I. ^#Mann-Whitney U test.

BNP, pg/mL

372.92 ± 324.75
245.19

430.13 ± 320.39
281.66

0.52^#

TnI, ng/mL

1.78 ± 6.13
0.12

7.11 ± 13.21
1.38

0.01^#

**Table 5.** Echocardiographic Parameters With BNP Levels
Variables	BNP ≥ 400 pg/mL (n = 23)	BNP < 400 pg/mL (n = 38)	P
Data are shown as median ± standard deviation, and median. BNP: brain natriuretic peptide; DT: deceleration time; E/A: ratio of early to late diastolic filling; E/E’: ratio of early mitral inflow filling to tissue Doppler early filling velocity; LA: left atrium; LA vol index: left atrial volume index; LVEDD: left ventricular end-diastolic diameter; LVEF: left ventricular ejection fraction; LVESD: left ventricular end -systolic diameter; LVMI: left ventricular mass index; RA: right atrium; RVFAC: right ventricular fractional area change; TAPSE: tricuspid annular plane systolic excursion. Mann-Whitney U test. *Independent groups t-test.
LA, mm	40.16 ± 4.60	39.67 ± 3.85	0.599**
LA vol index	24.65 ± 8.88 21.24	25.72 ± 7.70 25.86	0.594*
LVEDD, mm	52.53 ± 2.53 53	49.51 ± 4.21 49	0.001*
LVESD, mm	36.71 ± 4.15	33.92 ± 3.94	0.004**
LVEF, %	55.23 ± 7.28	58.92 ± 6.36	0.018**
LVMI, g/m²	118.34 ± 25.23	106.39 ± 23.71	0.120**
E/E’ ratio	11.39 ± 5.63 11.43	10.70 ± 4.68 9.12	0.634*
DT, ms	201.35 ± 52.94	222.89 ± 64.50	0.564**
E/A ratio	1.32 ± 0.83 0.98	1.05 ± 0.50 0.91	0.634*
RA diameter, mm	43.59 ± 4.89	40.97 ± 6.98	0.059**
TAPSE, mm	18.41 ± 2.67	20.00 ± 2.96	0.042**
RVFAC, %	48.86 ± 8.35	52.16 ± 10.67	0.219**

Table 5. Echocardiographic Parameters With BNP Levels

Variables

BNP ≥ 400 pg/mL (n = 23)

BNP < 400 pg/mL (n = 38)

Data are shown as median ± standard deviation, and median. BNP: brain natriuretic peptide; DT: deceleration time; E/A: ratio of early to late diastolic filling; E/E’: ratio of early mitral inflow filling to tissue Doppler early filling velocity; LA: left atrium; LA vol index: left atrial volume index; LVEDD: left ventricular end-diastolic diameter; LVEF: left ventricular ejection fraction; LVESD: left ventricular end -systolic diameter; LVMI: left ventricular mass index; RA: right atrium; RVFAC: right ventricular fractional area change; TAPSE: tricuspid annular plane systolic excursion. *Mann-Whitney U test. **Independent groups t-test.

LA, mm

40.16 ± 4.60

39.67 ± 3.85

0.599**

LA vol index

24.65 ± 8.88
21.24

25.72 ± 7.70
25.86

0.594*

LVEDD, mm

52.53 ± 2.53
53

49.51 ± 4.21
49

0.001*

LVESD, mm

36.71 ± 4.15

33.92 ± 3.94

0.004**

LVEF, %

55.23 ± 7.28

58.92 ± 6.36

0.018**

LVMI, g/m²

118.34 ± 25.23

106.39 ± 23.71

0.120**

E/E’ ratio

11.39 ± 5.63
11.43

10.70 ± 4.68
9.12

0.634*

DT, ms

201.35 ± 52.94

222.89 ± 64.50

0.564**

E/A ratio

1.32 ± 0.83
0.98

1.05 ± 0.50
0.91

0.634*

RA diameter, mm

43.59 ± 4.89

40.97 ± 6.98

0.059**

TAPSE, mm

18.41 ± 2.67

20.00 ± 2.96

0.042**

RVFAC, %

48.86 ± 8.35

52.16 ± 10.67

0.219**

**Table 6.** Correlation Between Brain Natriuretic Peptide Levels and Echocardiographic Parameters
Variables	Correlation level	P
LVMI: left ventricular mass index; RSm: tricuspid lateral annulus S wave; TAPSE: tricuspid annular plane systolic excursion. ^xPearson’s correlation analysis. ^!Significant at < 0.05.
RSm	-0.347^x	0.045^!
TAPSE	-0.402^x	0.018^!
LVMI	0.353^x	0.048^!

Table 6. Correlation Between Brain Natriuretic Peptide Levels and Echocardiographic Parameters

Variables

Correlation level

LVMI: left ventricular mass index; RSm: tricuspid lateral annulus S wave; TAPSE: tricuspid annular plane systolic excursion. ^xPearson’s correlation analysis. ^!Significant at < 0.05.

RSm

-0.347^x

0.045^!

TAPSE

-0.402^x

0.018^!

LVMI

0.353^x

0.048^!

**Table 7.** Stepwise Logistic Regression Analysis for Brain Natiuretic Peptide Levels
Variables	B	Odds ratio	95% confidence interval	P
SBP: systolic blood pressure; LVEDD: left ventricular end-diastolic diameter.
SBP	-0.029	0.972	0.947	0.996	0.025
LVEDD	0.281	1.324	1.090	1.607	0.005

Table 7. Stepwise Logistic Regression Analysis for Brain Natiuretic Peptide Levels

Variables

Odds ratio

95% confidence interval

Lower limit

Upper limit

SBP: systolic blood pressure; LVEDD: left ventricular end-diastolic diameter.

SBP

-0.029

0.972

0.947

0.996

0.025

LVEDD

0.281

1.324

1.090

1.607

0.005