The Expression Significance of LPa, BNP, and McP-1 in CHD Patients and Their Relationship with Echocardiographic Parameters.

In order to investigate the expression levels of Lipoprotein A (LPa), B-type Natriuretic Peptide (BNP) and Monocyte chemoattractor Protein-1 (McP-1) in serum of patients with coronary heart disease (CHD) are used to detect significance and to analyze the correlation between these indicators and parameters of echocardiography. The clinical data of 132 CHD patients in our hospital from January 2021 to October 2021 are retrospectively analyzed and included in the CHD group. Another 100 healthy people who came to our hospital for general physical examination were selected as the control group. The expressions of Serum McP-1 and BNP are detected by the ELISA. The expression of Serum LPa is detected by immunoturbidimetry, and the expressions of SERUM McP-1, BNP, and LPa are compared between the two groups. The experiments show that the expressions of McP-1, BNP, and LPa in serum of control group are significantly lower than those of the CHD group (P < 0.05). Echocardiography results show that left ventricular ejection fraction (LVEF) in CHD group is significantly lower than that in control group, but left ventricular end-systolic volume (LVESV) and left ventricular end-diastolic volume (LVEDV) are significantly higher than those in control group (P < 0.05).

1. Introduction

Coronary heart disease (CHD), caused by coronary atherosclerotic lesions, occurs in luminal stenosis, and the quality of the elderly's life and health of body and mind have a large impact [1, 2]. A large number of clinical studies have shown that factors causing CHD include age, family history, bad living habits, infection, and so on. Therefore, seeking a safe and efficient way to diagnose CHD is of great significance for timely treatment and improvement of prognosis of patients [3]. At present, coronary angiography is regarded as the gold standard for the diagnosis of CHD in clinical practice. However, this diagnostic method is complicated and requires high technical requirements of doctors, and may also cause injury or allergy risks to the body during the examination, so it is not a routine method for early diagnosis [4, 5]. In recent years, studies have shown that monocyte chemotactic Protein-1 (McP-1), as a kind of factor mediating the formation of foam cells in monocytes, also plays a role in the inflammatory response of atherosclerosis [6]. B-type natriuretic peptide, as one of the related hormones secreted by cardiomyocytes, also plays an important role in predicting adverse cardiovascular events [7]. In addition, as a blood lipid index, Lipoprotein A (LPa) may also play a certain role in the development of coronary heart disease [8], but there are relatively few studies on the above indexes. Based on this, this study further explores the expression of the above serum factors in CHD patients and the relationship between them and echocardiography parameters and also provides theoretical basis for early diagnosis and improvement of the prognosis of CHD patients.

The rest of this paper is organized as follows: Section 2 discusses related work, followed by investigating the expression levels of LPa, BNP, and McP-1 in serum of patients with CHD in Section 3. The results are shown and discussed in Section 4. Section 5 gives a conclusion.

2. Related Work

CHD as a cardiovascular disease caused by a variety of factors is usually clinically manifested as angina pectoris, myocardial infarction, and even sudden death due to heart failure in severe cases, which seriously threatens people's lives and health [9]. Epidemiological survey data in recent years show that the incidence and mortality rate of CHD are increasing year by year. Therefore, early diagnosis, prevention, and treatment of CHD are of great significance to reduce mortality and improve the prognosis of such patients [10]. Although coronary angiography diagnosis accuracy is higher, it belongs to have a check and owe high cost of inspection. There is some radioactive pollution, thus limiting its widely used in clinic, and echocardiography. Classic imaging methods of cardiac function, have some advantages, such as convenient, quick, and cheap. Therefore, combining detection of CHD with other indicators is a new approach for the diagnosis of CHD [11].

Some authors believed that McP-1, as a chemokine, belonged to monocytes and could play a dual role in arterial wall by reverse-regulating the adhesion of monocytes [12]. Blanco-Colio [13] also showed that McP-1 could activate monocytes and macrophages to form foam cells, thus participating in the inflammatory response in the early stage of atherosclerosis, and accelerating the proliferation of vascular smooth muscle cells to induce platelet aggregation. Therefore, patients with CHD may present with the elevated serum McP-1. In addition, LPa as a class of large molecules contains cholesterol lipoprotein. Moreover, it is not affected by age and the influence of external factors such as exercise and diet [14]. In addition, most epidemiological studies have shown that increased LPa is also a risk factor for predicting the incidence of CHD and ischemic stroke. Moreover, it is suggested that LPa is closely related to the incidence of CHD and other cardiovascular events [15-17]. In addition, BNP, as one of the indicators commonly, is used to detect impaired cardiac function in clinical practice. When myocardial cells are injured, the detectable BNP level in serum increases significantly [18-20]. When the myocardium is in the state of ischemia, the delayed movement of the myocardium will occur, and the compensatory movement of the surrounding tissues will be advanced, resulting in the imbalance of the coordination of myocardium movement and the decreasing of left ventricular ejection fraction (LVEF) of patients [21-25]. Left ventricular end-diastolic volume (LVEDV) and left ventricular end-systolic volume (LVESV), as the filling volume of left ventricle at the end of diastolic and systolic stages, refer to the maximum volume of blood that can be accommodated in each cardiac cycle. Due to the damage of cardiac myocytes and the imbalance of myocardial motor coordination, the volume of blood remaining in the cardiac chamber increases [26].

3. Materials and Methods

The clinical data of 132 CHD patients in our hospital from January 2021 to October 2021 were retrospectively analyzed and included in the CHD group. Another 100 healthy people who came to our hospital for general physical examination were selected as the control group. The comparison of baseline data of the two groups is shown in Table 1, which is comparable (P > 0.05). All patients have the right to know and consent to the test adopted in this study, and the study promises that the clinical information and general data collected will only be used for research and not for other purposes.

Table 1

Baseline data.

	CHD group (n = 132)	Control group (n = 100)	t/x2	P
Age (years)	56.52 ± 6.31	57.21 ± 6.17	−0.833	0.406
Gender			0.571	0.450
Man	74 (56.06%)	61 (61.00%)
Woman	58 (43.94%)	39 (39.00%)
BMI (kg/m2)	23.41 ± 2.19	23.43 ± 2.18	−0.069	0.945
Smoking			0.323	0.570
Y	81 (61.36%)	65 (65.00%)
N	51 (38.64%)	35 (35.00%)
Drinking			0.365	0.546
Y	78 (59.09%)	63 (63.00%)
N	54 (40.91%)	37 (37.00%)

Inclusion criteria contain the following parts.

Meet the clinical diagnostic criteria for coronary heart disease

Complete clinical data and general information

Have good communication skills and cooperate with research

Obtain informed consent for all tests performed in the study and use the clinical data for the study

Exclusion criteria contain the following information.

Absence of echocardiography parameters

People who deviate from the research results by taking other drugs without authorization

People with mental diseases

Poor compliance, unable to cooperate with study participants

Patients with dysfunction of heart, liver, kidney, and other organs

The left ventricular function of the included patients is measured by an ultrasound diagnostic instrument (Philips, Model: IEElite). All patients are in left decubital position during the examination. The probe is S5-1 cardiac probe, and the probe frequency is adjusted to 1∼3 MHz. Patients are instructed to hold their breath after deep exhalation, and four chambers of apical myocardium are taken through apical window. LVEDV, LVESV, and LVEF are measured by the two-plane Simpson method.

5 ml fasting venous blood of the two groups is taken in the morning and put into the centrifuge. The centrifuge parameters are adjusted to 3500 r/min and the centrifuge radius is 12 cm for 10 min centrifugation. After centrifugation, the supernatant is removed and put into the refrigerator at −80°C for detection. All the relevant determination kits are purchased from Shanghai Shenggong Bioengineering Co., LTD., and the experimental procedures are carried out in strict accordance with the kit operation instruction.

SPSS 25.0 statistical software is used for data analysis. (1) Measurement data: If data followed normal distribution and homogeneity of variance after normality test, they are represented by mean ± standard deviation. Paired sample T is used for an intragroup test, and variance comparison is used between groups. (2) Count data: descriptive statistical analysis is conducted by percentage. (3) Pearson correlation coefficient is used to analyze the correlation between serum McP-1, BNP, LPa, and parameters of echocardiography. (4) The ROC curve is drawn to evaluate the diagnostic value of serum McP-1, BNP, and LPa combined with echocardiography parameters in coronary heart disease. All the above data show significant differences with P < 0.05.

4. Experiments of the Expression Significance of LPa, BNP, and McP-1 in CHD Patients

Table 2 shows the serum levels of McP-1, BNP, and LPa. It is clearly evident from Table 2 that the expressions of serum McP-1, BNP, and LPa in the control group are significantly lower than those in the CHD group (P < 0.05).

Table 2

The serum levels of McP-1, BNP, and LPa.

Group	n	MCP-1 (pg/ml)	BNP (pg/ml)	LPa (mmol/L)
CHD group	132	136.73 ± 24.43	87.73 ± 21.25	31.25 ± 6.02
Control group	100	102.37 ± 16.33	59.46 ± 11.37	20.63 ± 5.52
t		12.154	12.056	13.779
P		<0.001	<0.001	<0.001

Table 3 shows the result of the differences in echocardiography parameters. It is clearly evident from Table 3 that LVEF in the CHD group is significantly lower than that in control group, but LVESV and LVEDV in the CHD group are significantly higher than those in control group (P < 0.05).

Table 3

Differences in echocardiography parameters.

Group	n	LVEF (%)	LVESV (ml)	LVEDV (ml)
CHD group	132	45.32 ± 4.28	93.35 ± 18.42	139.63 ± 14.64
Control group	100	61.35 ± 5.35	61.29 ± 16.44	128.45 ± 12.31
t		−25.348	13.744	6.162
P		<0.001	<0.001	<0.001

Table 4 shows the relationship between McP-1, BNP, LPa, and LVEF. It is clearly evident from Table 4 that LVEF in MCP-1 is s lower than that in BNP and LPa.

Table 4

Relationship between McP-1, BNP, LPa, and LVEF.

	LVEF (%)
	r	P
MCP-1 (pg/ml)	−0.657	<0.001
BNP (pg/ml)	−0.719	<0.001
LPa (mmol/L)	−0.702	<0.001

Table 5 shows the relationship between McP-1, BNP, and LVEDV. It is clearly evident from Table 5 that LVEF in LPa is s lower than that in BNP and MCP-1.

Table 5

Relationship between McP-1, BNP, LPa, and LVEDV.

	LVEDV (ml)
	r	P
MCP-1 (pg/ml)	0.526	<0.001
BNP (pg/ml)	0.572	<0.001
LPa (mmol/L)	0.516	<0.001

Table 6 shows the relationship between McP-1, BNP, LPa, and LVESV. It is clearly evident from Table 6 that LVEF in LPa is s the lowest among them.

Table 6

Relationship between McP-1, BNP, LPa, and LVESV.

	LVESV (ml)
	r	P
MCP-1 (pg/ml)	0.568	<0.001
BNP (pg/ml)	0.573	<0.001
LPa (mmol/L)	0.561	<0.001

Figure 1 displays the relationship between McP-1, BNP, LPa, and LVEF. It is clearly evident from Figure 1 that McP-1, BNP, and LPa are significantly negatively correlated with LVEF.

Figure 1

Relationship between McP-1, BNP, LPa, and LVEF: (a) relationship between McP-and LVEF; (b) relationship between BNP and LVEF; and (c) relationship between LPa and LVEF.

Figure 2 displays the relationship between McP-1, BNP, LPa, and LVESV. It is clearly evident from Figure 1 that McP-1, BNP, and LPa are significantly positively correlated with LVESV.

Figure 2

Relationship between McP-1, BNP, LPa, and LVEDV: (a) relationship between McP-1 and LVEDV; (b) relationship between BNP and LVEDV; and (c) relationship between LPa and LVEDV.

Figure 3 displays relationship between McP-1, BNP, LPa, and LVESV. It is clearly evident from Figure 1 that McP-1, BNP, and LPa are significantly positively correlated with LVEDV.

Figure 3

Relationship between McP-1, BNP, LPa, and LVESV: (a) relationship between McP-1 and LVESV; (b) relationship between BNP and LVESV; and (c) relationship between LPa and LVESV.

Table 7 shows the diagnostic efficiency of each index. It is clearly evident from Table 7 that serum McP-1, BNP, and LPa combined with LVEF have high diagnostic efficacy for the early diagnosis of CHD.

Table 7

Diagnostic efficiency of each index.

	95%CI	Sensitivity (%)	Specificity (%)	AUC	Cutoff value
The joint detection	0.827–0.968	88.40	86.30	0.898
LVEF	0.777–0.933	83.20	81.20	0.803	50.00%
MCP-1	0.650–0.875	76.30	69.40	0.763	112.45
BNP	0.605–0.833	77.30	71.20	0.719	71.24
LPa	0.586–0.812	70.30	68.30	0.699	25.31

Figure 4 displays the ROC curve to evaluate the diagnostic efficacy of combined assays. It is clearly evident from Figure 4 that the area under the curve of the combined test is significantly higher than that of any single test, indicating good diagnostic efficacy.

Figure 4

ROC curve to evaluate the diagnostic efficacy of combined assays.

The results of echocardiography show that LVEF of CHD patients is significantly lower than that of the control group, but LVEDV and LVESV are significantly higher than that of the control group, mainly because LVEF is one of the main indicators to evaluate the left ventricular systolic function in clinic. For the healthy population, the normal pumping function of the heart is completed by the good contraction and coordination movement of the myocardium. According to Person correlation coefficient, McP-1, BNP, and LPa are significantly negatively correlated with LVEF, but significantly positively correlated with LVESV and LVEDV. The main reason is that the increased expression of McP-1, BNP, and LPa suggest that patients' myocardial cells are damaged to varying degrees, leading to the decline of myocardial function, and the imbalance of myocardial movement leads to the increase of cardiac contraction and end-diastolic filling. The results show that serum index of joint echocardiography in diagnosis of early CHD owns high efficiency and its operation compared with coronary angiography is relatively simple. Therefore, it can be used as a diagnostic basis for CHD.

5. Conclusion

In conclusion, serum McP-1, BNP, LPa, and echocardiography of CHD patients have specific manifestations in the clinical detection process, and there is a close relationship between them. The combined detection of serum indicators and echocardiography has high diagnostic efficiency for CHD and has a certain clinical application value. However, this study is a small sample size study, so the accuracy of the research results needs to be further verified by other scholars and large sample size studies.