Gastroenterology Research and Practice
Volume 2020 (2020), Article ID 4019289, 15 pages
https://doi.org/10.1155/2020/4019289

Research Article

Correlation of Serum Cardiac Markers with Acute Decompensating Events in Liver Cirrhosis

Miaomiao Li,1,2 Zeqi Guo,¹ Dan Zhang,³ Xiangbo Xu,1,4 Fernando Gomes Romeiro,⁵ Andrea Mancuso,⁶ Jingqiao Zhang,1,4 Ruirui Feng,¹ Xinmiao Zhou,¹ Cen Hong,¹ and Xingshun Qi¹

¹Liver Cirrhosis Group, Department of Gastroenterology, General Hospital of Northern Theater Command (Formerly General Hospital of Shenyang Military Area), Shenyang, China
²Department of Clinical Laboratory, The First Hospital of Lanzhou University, Lanzhou, China
³Department of General Surgery, General Hospital of Northern Theater Command (Formerly General Hospital of Shenyang Military Area), Shenyang, China
⁴Department of Pharmaceutical Sciences, Shenyang Pharmaceutical University, Shenyang, China
⁵Faculdade de Medicina de Botucatu UNESP, Campus de Botucatu, S/N, Botucatu, SP, Brazil
⁶Department of Internal Medicine, ARNAS Civico, Palermo, Italy

Correspondence should be addressed to Xingshun Qi; xingshunqi@126.com

Received 7 May 2020; Revised 1 September 2020; Accepted 14 September 2020; Published 24 September 2020

Academic Editor: Niccola Funel

Copyright © 2020 Miaomiao Li et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract.

Background and Aim. Liver cirrhosis is often accompanied by insidious cardiac dysfunction. This retrospective cross-sectional study is aimed at exploring the correlation between serum cardiac markers and decompensating events in liver cirrhosis. Methods. Cirrhotic patients who were consecutively hospitalized between January 2016 and March 2019 were screened. Serum cardiac biomarkers at admission, including N-Terminal pro-B-type natriuretic peptide (NT-pro BNP), high-sensitivity cardiac troponin T (hs-cTnT), creatine kinase (CK), creatine kinase MB (CK-MB), and lactate dehydrogenase (LDH), were collected. Acute decompensating events at admission, primarily including ascites, acute gastrointestinal hemorrhage, and acute-on-chronic liver failure (ACLF), were recorded. Results. The NT-pro BNP level was significantly higher in cirrhotic patients with acute decompensating events than in those without any decompensating events (median: 140.75 pg/mL versus 41.86 pg/mL, ). The NT-pro BNP level significantly correlated with ascites, acute gastrointestinal hemorrhage, and ACLF. The hs-cTnT level was significantly higher in cirrhotic patients with acute decompensating events than in those without decompensating events (median: 0.008 ng/mL versus 0.006 ng/mL, ). The hs-cTnT level significantly correlated with acute gastrointestinal hemorrhage, but not ascites or ACLF. LDH (185.0 U/L versus 173.5 U/L, ), CK (71 U/L versus 84 U/L, ), and CK-MB (29.5 U/L versus 33.0 U/L, ) levels were not significantly different between cirrhotic patients with and without acute decompensating events. Conclusion. The elevated NT-pro BNP level seems to be closely related to the development of acute decompensating events in liver cirrhosis.

1. Introduction

Liver cirrhosis is a state of systemic hyperdynamic circulation characterized by increased cardiac output and decreased peripheral resistance, especially in the presence of decompensating events [1]. This disease activates the sympathetic nervous system (SNS) and the renin-angiotensin-aldosterone system (RAAS), which further increases the myocardial tension and ultimately results in chronic cardiac dysfunction [2–4]. Consequently, the levels of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and troponin I (TnI) are increased [5]. Such chronic cardiac dysfunction in liver cirrhosis presenting with systolic dysfunction, diastolic dysfunction, and electrophysiological changes is known as “cirrhotic cardiomyopathy” [4]. An interaction between liver cirrhosis and cardiac dysfunction suggests that serum cardiac markers may be valuable in evaluating the disease state of liver cirrhosis.

BNP and N-Terminal pro-B-type natriuretic peptide (NT-pro BNP) are secreted in response to increased myocardial stress [6–8]. The NT-pro BNP level is significantly increased in liver cirrhosis, which may be related to cardiac dysfunction [9–11]. Also, the NT-pro BNP level significantly correlates with the severity of liver dysfunction and prognosis of cirrhotic patients [7, 12]. On the other hand, high-sensitivity cardiac troponin T (hs-cTnT), another highly specific and sensitive marker of myocardial injury, is also significantly increased in patients with liver cirrhosis. Thus, NT-pro BNP as well as hs-cTnT may be valuable for prognostic assessment of liver cirrhosis [12]. However, their correlation with acute decompensating events in liver cirrhosis has never been explored yet. Additionally, the clinical significance of other biomarkers of cardiac injury, such as creatine kinase (CK), creatine kinase MB (CK-MB), and lactate dehydrogenase (LDH), in liver cirrhosis remains unclear.

Therefore, this study is aimed at exploring the relationship between these cardiac markers and decompensating events in cirrhosis.

2. Methods

2.1. Patients

We have prospectively collected the demographic, clinical, and laboratory data of cirrhotic patients who were consecutively admitted to the Department of Gastroenterology of the General Hospital of Northern Theater Command (formerly General Hospital of Shenyang Military Area) and treated by an attending physician (XQ) since January 1, 2016. Until March 31, 2019, there were a total of 761 admissions. We retrospectively screened the patients who had undergone the evaluation of laboratory data regarding serum cardiac markers during the hospitalizations. Exclusion criteria were as follows: (1) confirmed or suspected diagnosis of malignancy, (2) severe renal insufficiency (estimated glomerular filtration  mL/min/1.73 m²), (3) cardiac diseases (i.e., heart failure, coronary atherosclerotic heart disease, and atrial fibrillation), (4) ischemic stroke, and (5) absence of data regarding serum cardiac markers detected during the hospitalizations. Repeated admissions of the same patient were not deliberately excluded, because this study focused on the in-hospital outcome and decompensating events during the hospitalizations, but not on long-term follow-up outcomes. If a patient had multiple measurements of serum cardiac markers during the same hospitalization, we selected the data obtained at the first time of blood collection. The study protocol was approved by the Medical Ethics Committee of our hospital. We primarily collected demographic data, etiology of liver cirrhosis, decompensating events at admissions, and laboratory tests including serum cardiac markers.

2.2. Definitions and Diagnosis

Acute gastrointestinal hemorrhage was defined as previously described [13, 14]. The Child-Pugh score was calculated [15]. Model for end-stage liver disease (MELD) and MELD with sodium (MELD-Na) scores were calculated according to an equation updated by the OPTN/UNOS (American Organ Acquisition and Transplantation Network/Organ Resource Sharing Network) in 2016 [16], as follows:

If  mmol/L, it is set to 125; if , it is set to 137.

The grade of ascites was defined according to the consensus of the International Ascites Club [17]. Patients with acute-on-chronic liver failure (ACLF) were identified by the recommendations of the Asian Pacific Association for the Study of the Liver (APASL) consensus [18, 19]. Severe renal insufficiency was defined as  mL/min/1.73 m² [20]. The eGFR was calculated using the simplified equation [21], as follows:

2.3. Groups

We divided cirrhotic patients into 5 groups: (1) cirrhotic patients without acute decompensating events, (2) cirrhotic patients with acute decompensating events, (3) cirrhotic patients with ascites, (4) cirrhotic patients with acute gastrointestinal hemorrhage, and (5) cirrhotic patients with ACLF.

2.4. Measurement of Serum Cardiac Markers

All serum cardiac markers were measured at the Department of Laboratory of our hospital. They included NT-pro BNP detected by enzyme-linked immunosorbent assay (ELISA) (double antibody sandwich method) with a normal range of 0-125 pg/mL, hs-cTnT by ELISA (double antibody sandwich method) with a normal range of 0-0.05 ng/mL, CK by coupled-enzyme assay with a normal range of 38-174 U/L, CK-MB by immune inhibition assay with a normal range of 0-24 U/L, LDH by the spectrophotometric method with a normal range of 109-245 U/L, and hs-CRP by latex immune turbidimetry with a normal range of 0-3 mg/L. Only the data obtained at the first time of measurement were selected, thus avoiding the influence of drugs used during hospitalization.

2.5. Statistical Analyses

Continuous data were expressed as and median (quartiles) and were compared by using the Wilcoxon rank-sum test. Categorical data were expressed as frequency (percentage) and were compared by using the chi-square test. Considering that age and gender are important factors influencing serum NT-pro BNP and hs-cTnT levels [22–26], partial correlation analysis was adjusted for age and gender to analyze the correlation of serum NT-pro BNP and hs-cTnT with liver disease conditions. Pearson or Spearman tests were performed to analyze the correlation between disease conditions and other serological cardiac markers, such as CK, CK-MB, and LDH. Multivariate linear regression analysis was performed to analyze the correlation of serological cardiac markers with categorical variables. A two-sided was considered to be statistically significant. SPSS statistics software version R23.0.0.0 was employed to perform all statistical analyses.

3. Results

3.1. Patients

Overall, 176 patients with liver cirrhosis were included (Figure 1), of whom 42 (23.86%) did not have any decompensating events but conducted regular follow-up and/or prophylactic endoscopic variceal treatment and 134 (76.14%) had acute decompensating events, including ascites (, 71.64%), acute gastrointestinal hemorrhage (, 64.18%), and ACLF (, 7.46%).

Figure 1: A flow chart of patient selection.

3.2. Comparison between Cirrhotic Patients with and without Decompensating Events

Cirrhotic patients with decompensating events had significantly higher levels of NT-pro BNP () and hs-cTnT () than those without decompensating events (Figure 2), but the differences in the levels of CK, CK-MB, and LDH were not significant between them (Table 1).

(a)

(b)

(c)

(d)

(e)

Figure 2: Box plots showing the concentrations of serum NT-pro BNP (a), hs-cTnT (b), CK (c), CK-MB (d), and LDH (e) in general cirrhotic patients, cirrhotic patients with and without decompensating events, cirrhotic patients with ascites, cirrhotic patients with acute gastrointestinal hemorrhage, and cirrhotic patients with ACLF. Notes: and .

Table 1: Comparison of characteristics of cirrhotic patients without and with decompensating events.

Variables
Without decompensation
With decompensation
value

No. Pts
; median (range) or frequency (percentage)
No. Pts
; median (range) or frequency (percentage)

Sex (male/female), (%)
42
35 (83.33%)/7 (16.67%)
134
89 (66.42%)/45 (33.58%)
0.051

Age (years)
42
; 52.5 (46.50-62.25)
134
; 55.00 (47.00-65.00)
0.130

Causes of liver diseases, (%)
42

134

Hepatitis B virus alone
14
14 (33.33%)
48
48 (35.82%)
/

Hepatitis C virus alone
4
4 (9.52%)
9
9 (6.72%)
/

Alcohol alone
12
12 (28.57%)
29
29 (21.64%)
/

Hepatitis B virus+alcohol
1
1 (2.38%)
4
4 (2.99%)
/

Autoimmune
1
1 (2.38%)
16
16 (11.94%)
/

Drug
1
1 (2.38%)
6
6 (4.48%)
/

Others
1
1 (2.38%)
0
0 (0%)
/

Red blood cell (10¹²/L)
42
; 4.05 (3.62-4.57)
134
; 3.10 (2.56-3.76)
<0.001

Hemoglobin (g/L)
42
; 123.00 (108.00-131.25)
134
; 91.50 (70.00-115.00)
<0.001

Hematocrit (%)
42
; 36.60 (32.88-39.63)
134
; 28.20 (21.90-34.73)
<0.001

White blood cell (10⁹/L)
42
; 3.35 (2.45-4.65)
134
; 3.70 (2.60-6.03)
0.155

Platelet count (10⁹/L)
42
; 71.00 (48.50-104.75)
134
; 76.00 (53.50-107.50)
0.433

Total bilirubin (μmol/L)
42
; 22.90 (16.15-32.45)
134
; 23.15 (15.15-45.13)
0.682

Direct bilirubin (μmol/L)
42
; 9.90 (6.25-13.75)
134
; 10.50 (6.08-20.73)
0.351

Alanine aminotransferase (U/L)
42
; 26.29 (17.86-37.58)
134
; 23.43 (15.80-38.64)
0.391

Aspartate aminotransferase (U/L)
42
; 32.73 (24.25-50.47)
134
; 32.71 (23.91-59.55)
0.753

Alkaline phosphatase (U/L)
42
; 96.34 (77.34-139.58)
134
; 95.93 (67.99-143.13)
0.612

Gamma-glutamyl transpeptidase (U/L)
42
; 49.94 (27.53-83.88)
134
; 41.56 (19.87-93.42)
0.429

Albumin (g/L)
42
; 37.35 (32.38-41.03)
134
; 30.80 (25.60-35.80)
<0.001

Blood urea nitrogen (mmol/L)
42
; 4.87 (3.79-6.19)
134
; 6.05 (4.39-7.87)
0.007

Creatinine (μmol/L)
42
; 64.68 (56.02-74.81)
134
; 65.20 (53.53-78.15)
0.694

eGFR (mL/min/1.73 m²)
42
; 118.40 (97.75-133.97)
134
; 106.52 (84.22-133.52)
0.068

Na (mmol/L)
42
; 139.45 (137.80-140.43)
134
; 138.45 (136.00-141.00)
0.226

Prothrombin time (second)
42
; 16.05 (15.03-16.88)
134
; 16.70 (15.10-18.90)
0.033

Activated partial thromboplastin time (second)
42
; 41.60 (38.98-45.53)
134
; 40.15 (37.10-44.30)
0.149

International normalized ratio
42
; 1.28 (1.19-1.38)
134
; 1.36 (1.20-1.58)
0.040

D-dimer (mg/L)
41
; 0.60 (0.29-1.27)
131
; 1.81 (0.72-4.41)
<0.001

High-sensitivity C-reactive protein (mg/L)
41
; 2.20 (0.90-6.60)
133
; 5.70 (1.35-14.10)
0.016

MELD score
42
; 10.26 (9.04-13.06)
134
; 11.32 (9.22-16.56)
0.093

Child-Pugh score
42
; 6.00 (5.00-6.00)
134
; 7.00 (6.00-9.00)
<0.001

Child-Pugh class
42

134

    A, (%)
33
33 (78.57%)
44
44 (32.84%)
<0.001

    B, (%)
9
9 (21.43%)
58
58 (43.28%)
<0.001

    C, (%)
0
0 (0%)
32
32 (23.88%)
<0.001

NT-pro BNP (pg/mL)
38
; 41.86 (20.36-69.16)
120
; 140.75 (62.34-401.33)
<0.001

High-sensitivity cardiac troponin T (ng/mL)
42
0; 0.006 (0.003-0.008)
128
; 0.008 (0.015-0.003)
0.007

Creatine kinase (U/L)
42
; 84.00 (53.50-123.75)
132
; 71.00 (44.00-105.50)
0.157

Creatine kinase MB (U/L)
42
; 33.00 (19.00-47.25)
132
; 29.5 (19.25-46.25)
0.604

Lactate dehydrogenase (U/L)
42
; 173.50 (137.50-211.50)
132
; 185.00 (152.00-226.75)
0.281

Bold font indicates statistically significant values. Abbreviations: eGFR: the estimated glomerular filtration rate; MELD: model for end-stage liver disease; NT-pro BNP: N-Terminal pro-B-type natriuretic peptide.

Cirrhotic patients with ascites had significantly higher levels of NT-pro BNP () and hs-cTnT () than those without decompensating events (Figure 2), but the differences in the levels of CK, CK-MB, and LDH were not significant between them (Table 2).

Table 2: Comparison of characteristics of cirrhotic patients with ascites, acute gastrointestinal hemorrhage, ACLF, and without decompensating events.

Variables
With ascites
With acute gastrointestinal hemorrhage
With ACLF

No. Pts
; median (range) or frequency (percentage)
value
No. Pts
; median (range) or frequency (percentage)
value
No. Pts
; median (range) or frequency (percentage)
value

Sex (male/female), (%)
96
64 (66.67%)/32 (33.33%)
0.064
86
56 (65.12%)/30 (34.88%)
0.039
10
8 (80%)/2 (20%)
0.558

Age (years)
96
; 60.00 (48.00-65.75)
0.027
86
; 54.00 (45.00-63.25)
0.692
10
; 48.00 (45.00-57.00)
0.429

Red blood cell (10¹²/L)
96
; 3.08 (2.57-3.83)
<0.001
86
; 2.75 (2.39-3.35)
<0.001
10
; 2.60 (1.78-3.45)
<0.001

Hemoglobin (g/L)
96
; 93.00 (70.00-113.75)
<0.001
86
; 76.00 (66.00-99.00)
<0.001
10
; 98.50 (65.25-117.25)
0.018

Hematocrit (%)
96
; 28.40 (21.38-34.33)
<0.001
86
; 23.15 (20.33-30.20)
<0.001
10
; 28.80 (18.58-34.75)
0.004

White blood cell (10⁹/L)
96
; 3.85 (2.73-6.18)
0.119
86
; 3.60 (2.38-6.30)
0.390
10
; 6.15 (4.43-8.25)
0.021

Platelet count (10⁹/L)
96
; 78.00 (54.00-106.75)
0.384
86
; 72.50 (51.00-103.75)
0.755
10
; 64.50 (39.00-97.25)
0.562

Total bilirubin (μmol/L)
96
; 28.90 (15.38-63.15)
0.186
86
; 19.55 (13.20-32.20)
0.292
10
; 166.20 (121.25-223.50)
<0.001

Direct bilirubin (μmol/L)
96
; 13.45 (6.43-37.53)
0.039
86
; 8.45 (5.40-16.23)
0.582
10
; 105.10 (82.08-184.23)
<0.001

Alanine aminotransferase (U/L)
96
; 23.09 (16.25-39.37)
0.517
86
; 20.92 (14.62-36.63)
0.132
10
; 51.43 (23.77-63.76)
0.012

Aspartate aminotransferase (U/L)
96
; 34.56 (24.01-68.95)
0.404
86
; 27.45 (20.43-48.41)
0.232
10
; 93.55 (65.65-128.31)
<0.001

Alkaline phosphatase (U/L)
96
;
101.99 (75.12-149.67)
0.621
86
; 81.09 (59.99-110.37)
0.019
10
; 137.08 (84.14-169.98)
0.202

Gamma-glutamyl transpeptidase (U/L)
96
; 46.21 (21.10-108.21)
0.901
86
; 29.01 (16.74-57.98)
0.032
10
; 67.05 (37.05-97.91)
0.218

Albumin (g/L)
96
; 29.65 (25.10-33.40)
<0.001
86
; 31.10 (25.68-36.18)
<0.001
10
; 22.80 (19.95-26.98)
<0.001

Blood urea nitrogen (mmol/L)
96
; 6.05 (4.42-7.86)
0.007
86
; 6.25 (4.39-8.46)
0.003
10
; 6.26 (4.78-11.15)
0.070

Creatinine (μmol/L)
96
; 63.55 (53.23-82.68)
0.686
86
; 65.86 (52.78-75.94)
0.895
10
; 61.15 (52.53-101.95)
0.763

eGFR (mL/min/1.73 m²)
96
; 104.38 (77.60-133.84)
0.047
86
; 108.07 (86.83-138.32)
0.247
10
; 107.84 (73.24-137.83)
0.403

Na (mmol/L)
96
; 137.75 (134.93-140.95)
0.041
86
; 139.35 (136.55-141.03)
0.741
10
; 135.20 (131.55-139.15)
0.021

Prothrombin time (second)
96
; 17.15 (15.60-20.45)
0.001
86
; 16.90 (15.20-19.10)
0.026
10
; 22.85 (20.65-27.95)
<0.001

Activated partial thromboplastin time (second)
96
; 41.90 (37.73-47.28)
0.987
86
; 39.70 (36.98-43.98)
0.064
10
; 52.85 (46.63-55.95)
<0.001

International normalized ratio
96
; 1.40 (1.25-1.75)
0.001
86
; 1.37 (1.21-1.60)
0.031
10
; 1.99 (1.77-2.59)
<0.001

D-dimer (mg/L)
95
; 2.28 (0.93-4.64)
<0.001
83
; 1.43 (0.58-3.57)
0.001
9
; 4.51 (3.41-9.02)
<0.001

High-sensitivity C-reactive protein (mg/L)
95
; 6.90 (2.20-20.30)
0.001
85
; 4.50 (1.20-11.55)
0.071
10
; 30.65 (11.35-75.35)
<0.001

MELD score
96
; 13.50 (10.07-18.23)
0.001
86
; 10.65 (9.13-14.42)
0.343
10
; 28.14 (21.24-30.04)
<0.001

Child-Pugh score
96
; 8.00 (7.00-10.00)
<0.001
86
; 7.00 (6.00-8.00)
<0.001
10
; 12.00 (11.75-13.00)
<0.001

NT-pro BNP (pg/mL)
87
; 165.20 (71.06-415.80)
<0.001
78
; 144.95 (60.82-443.93)
<0.001
10
; 212.30 (150.70-1662.75)
<0.001

High-sensitivity cardiac troponin T (ng/mL)
92
; 0.008 (0.005-0.014)
0.002
81
; 0.009 (0.005-0.014)
0.003
9
; 0.007 (0.005-0.035)
0.157

Creatine kinase (U/L)
95
; 69.00 (45.00-97.00)
0.099
84
; 69.00 (40.50-105.50)
0.117
10
; 71.50 (41.25-109.00)
0.501

Creatine kinase MB (U/L)
95
; 29.00 (20.00-42.00)
0.463
84
; 29.50 (19.00-43.75)
0.552
10
; 22.50 (14.50-36.00)
0.163

Lactate dehydrogenase (U/L)
95
; 195.00 (154.00-232.00)
0.076
84
; 171.00 (140.00-206.25)
0.727
10
; 235.00 (157.50-317.25)
0.050

Bold font indicates statistically significant values. Abbreviations: ACLF: acute-on-chronic liver failure; eGFR: the estimated glomerular filtration rate; MELD: model for end-stage liver disease; NT-pro BNP: N-Terminal pro-B-type natriuretic peptide.

Cirrhotic patients with acute gastrointestinal hemorrhage had significantly higher levels of NT-pro BNP () and hs-cTnT () than those without decompensating events (Figure 2), but the differences in the levels of CK, CK-MB, and LDH were not significant between them (Table 2).

Cirrhotic patients with ACLF had a significantly higher level of NT-pro BNP () than those without decompensating events (Figure 2), but the differences in the levels of CK, CK-MB, and LDH were not significant between them (Table 2).

3.3. Correlation of Serum Cardiac Markers with Child-Pugh and MELD Scores in Patients with Liver Cirrhosis

Partial correlation analyses demonstrated that the NT-pro BNP level significantly correlated with Child-Pugh and MELD scores. These correlations were observed in all the cirrhotic patients and in those with decompensating events, but not in those without decompensating events (Table 3). Partial correlation analyses demonstrated that the hs-cTnT level had no significant correlation with Child-Pugh and MELD scores in cirrhotic patients regardless of the presence of decompensating events (Supplementary Table 1). Correlation analyses demonstrated that CK (Supplementary Table 2) and CK-MB (Supplementary Table 3) levels did not significantly correlate with Child-Pugh and MELD scores in cirrhotic patients. On the other hand, the LDH level significantly correlated with Child-Pugh and MELD scores in cirrhotic patients (Supplementary Table 4).

Table 3: Partial correlation analysis of the NT-pro BNP level in cirrhosis.

Variables
All liver cirrhosis
Liver cirrhosis without decompensation
Liver cirrhosis with decompensation

No. Pts
value
Correlation coefficient
No. Pts
value
Correlation coefficient
No. Pts
value
Correlation coefficient

Age (years)
/
Controlling
/
/
Controlling
/
/
Controlling
/

Sex (male/female), (%)
/
Controlling
/
/
Controlling
/
/
Controlling
/

Red blood cell (10¹²/L)
154
<0.001
-0.322
34
0.023
-0.379
116
0.001
-0.313

Hemoglobin (g/L)
154
0.004
-0.229
34
0.001
-0.540
116
0.025
-0.207

Hematocrit (%)
154
0.001
-0.254
34
0.001
-0.523
116
0.011
-0.234

White blood cell (10⁹/L)
154
0.027
0.177
34
0.093
-0.284
116
0.058
0.175

Platelet count (10⁹/L)
154
0.894
-0.011
34
0.201
-0.218
116
0.842
-0.018

Total bilirubin (μmol/L)
154
0.027
0.178
34
0.755
-0.054
116
0.054
0.178

Direct bilirubin (μmol/L)
154
0.063
0.149
34
0.661
-0.076
116
0.113
0.146

Alanine aminotransferase (U/L)
154
0.715
-0.029
34
0.534
-0.107
116
0.609
-0.048

Aspartate aminotransferase (U/L)
154
0.694
-0.032
34
0.493
-0.118
116
0.687
-0.037

Alkaline phosphatase (U/L)
154
0.534
-0.050
34
0.071
-0.304
116
0.623
-0.046

Gamma-glutamyl transpeptidase (U/L)
154
0.983
-0.002
34
0.206
-0.216
116
0.794
0.024

Albumin (g/L)
154
0.006
-0.219
34
0.263
-0.192
116
0.042
-0.188

Blood urea nitrogen (mmol/L)
154
0.022
0.183
34
0.099
0.279
116
0.074
0.165

Creatinine (μmol/L)
154
0.692
-0.032
34
0.755
-0.054
116
0.547
-0.056

eGFR (mL/min/1.73 m²)
154
0.073
0.144
34
0.823
0.039
116
0.058
0.175

Sodium (mmol/L)
154
0.039
-0.165
34
0.586
0.094
116
0.082
-0.161

Prothrombin time (second)
154
<0.001
0.416
34
0.480
0.122
116
<0.001
0.419

Activated partial thromboplastin time (second)
154
0.023
0.182
34
0.406
0.143
116
0.030
0.200

International normalized ratio
154
<0.001
0.436
34
0.380
0.151
116
<0.001
0.439

D-dimer (mg/L)
153
0.003
0.241
34
0.125
0.260
115
0.040
0.190

High-sensitivity C-reactive protein (mg/L)
153
<0.001
0.285
33
0.576
0.098
116
0.003
0.270

MELD score
154
<0.001
0.302
34
0.701
0.066
116
0.001
0.296

Child-Pugh score
154
<0.001
0.346
34
0.279
0.185
116
<0.001
0.325

High-sensitivity cardiac troponin T (ng/mL)
151
0.004
0.229
34
0.062
-0.315
113
0.026
0.208

Creatine kinase (U/L)
154
0.653
-0.036
34
0.567
0.099
116
0.588
-0.050

Creatine kinase MB (U/L)
154
0.209
-0.101
34
0.744
-0.056
116
0.217
-0.115

Lactate dehydrogenase (U/L)
154
0.622
-0.040
34
0.985
-0.003
116
0.586
-0.051

Bold font indicates statistically significant values. Abbreviations: NT-pro BNP: N-Terminal pro-B-type natriuretic peptide; eGFR: the estimated glomerular filtration rate; MELD: model for end-stage liver disease.

3.4. Correlation between Serum Cardiac Markers and Decompensating Events in Cirrhotic Patients

Age- or gender-adjusted multivariate linear regression analyses demonstrated that the NT-pro BNP level significantly correlated with overall acute decompensating events, ascites, acute gastrointestinal hemorrhage, and ACLF (Table 4); the hs-cTnT level significantly correlated with overall acute decompensating events and acute gastrointestinal hemorrhage, but not ascites or ACLF (Supplementary Table 5); CK and CK-MB levels did not significantly correlate with overall acute decompensating events, ascites, acute gastrointestinal hemorrhage, or ACLF; the LDH level significantly correlated with ascites, acute gastrointestinal hemorrhage, and ACLF, but not overall acute decompensating events (Supplementary Table 6).

Table 4: Multivariate linear regression analysis of factors associated with the NT-pro BNP level.

Factors
No. Pts
Age-adjusted

-coefficient (SE)
value

Age
158
0.302 (0.008)
<0.001

Gender
158
0.106 (0.214)
0.137

Acute decompensating events
158
0.432 (0.229)
<0.001

Ascites
158
0.175 (0.195)
0.014

Acute gastrointestinal hemorrhage
158
0.309 (0.183)
<0.001

ACLF
158
0.218 (0.384)
<0.001

Bold font indicates statistically significant values. Serum NT-pro BNP concentrations were log₁₀-transformed in order to normalize their distribution. Abbreviations: NT-pro BNP: N-Terminal pro-B-type natriuretic peptide; SE: standard error; ACLF: acute-on-chronic liver failure.

4. Discussion

In this retrospective observational study, we rigorously screened the participants by excluding the confounding factors, which makes our statistical results more reliable. Additionally, we included a relatively large number of cirrhotic patients, which makes our conclusions more representative. The major findings are as follows: (i) the NT-pro BNP level was significantly higher in decompensated cirrhosis. (ii) The NT-pro BNP level also significantly correlated with Child-Pugh and MELD scores in cirrhosis with acute decompensation, but not in those without decompensation. (iii) The hs-cTnT level was elevated in cirrhosis with acute decompensation but was unrelated to the liver disease severity. (iv) The LDH level significantly correlated with Child-Pugh and MELD scores in cirrhosis, but was unrelated to decompensating events. (v) CK and CK-MB levels were neither significantly increased in cirrhosis with decompensation nor correlated with Child-Pugh and MELD scores.

4.1. NT-pro BNP

NT-pro BNP, a prohormone of BNP, is secreted into the systemic circulation by cardiac ventricles in response to myocardial hypertrophy and is involved in the regulation of cardiac volume homeostasis [27–29]. Thus, the NT-pro BNP level is often considered as an effective and useful marker for screening of early stages of cardiac dysfunction [30]. As we know, cirrhotic cardiomyopathy is a chronic cardiac systolic and diastolic dysfunction in cirrhotic patients in the absence of prior heart disease [31, 32]. There is no obvious abnormal change of cardiac function in the resting state; besides, a decreased afterload in cirrhosis often results in normal or even increased left ventricular ejection fraction [31]. Thus, noninvasive cardiac biomarkers are potentially useful to reflect the slight change of pressure state of end-diastolic wall stress and intracardiac filling pressures.

The serum NT-pro BNP level is significantly higher in patients with liver cirrhosis [7, 9, 10, 12, 33], probably because it is often associated with hyperdynamic circulation, such as increased heart rate and cardiac output, thereby impairing cardiac contractility [34–36]. Our study for the first time found that the serum NT-pro BNP level was significantly higher in cirrhotic patients who suffer an acute decompensation, such as ascites, gastrointestinal hemorrhage, and ACLF, when the values were compared to those without decompensation. Interestingly, we also found that the NT-pro BNP level significantly correlated with Child-Pugh and MELD scores in cirrhotic patients with acute decompensating events, but not in those without decompensation, which would suggest that NT-pro BNP can reflect the insidious change of cardiac dysfunction in advanced cirrhosis with cardiac dysfunction.

In addition, BNP is a natriuretic hormone released from myocardial cells in response to volume expansion, end-diastolic wall stress, and possibly increased intracardiac filling pressures [8, 37]. Hypertrophy of the left ventricle, left-atrial dilatation, and increased end-diastolic and end-systolic left-ventricular volume are frequently observed in liver cirrhosis [1, 32, 38, 39], which are potentially the main causes for an increase of NT-pro BNP.

4.2. hs-cTnT

hs-cTnT, a protein complex regulating the contraction of striated muscle, is released when myocardial ischemia induces nonreversible injury of myocardial tissue [40]. hs-cTnT is a specific and sensitive biomarker of myocardial damage and is being widely used for clinical screening in patients with suspected acute myocardial infarction [41, 42], but not for evaluating the change of myocardial contractility. The hs-cTnT level can be also elevated in some cardiac and noncardiac conditions, such as severe renal insufficiency [43–46], tachycardia, pericarditis, vigorous exercise [47], and atrial fibrillation [48–50]. The present study has rigorously excluded these conditions. The hs-cTnT level seems to be related to the severity and survival of cirrhotic patients [12, 14]. Our results also showed that the hs-cTnT level was significantly higher in decompensated cirrhotic patients than those without decompensation. This association was mainly attributed to the effect of acute gastrointestinal hemorrhage, but not to ascites or ACLF (Supplementary Table 5). A possible explanation for this finding could be that acute gastrointestinal bleeding in cirrhotic patients may lead to hypovolemic hypotension, which is a significant risk factor for myocardial damage [51–53], thereby increasing the levels of myocardial damage biomarkers [54]. The pathophysiological link of the association remains unexplained, and it needs further research to clarify its mechanism.

4.3. CK and CK-MB

We did not find any significant difference in CK and CK-MB levels, comparing compensated and decompensated cirrhotic patients. Moreover, there was no correlation of CK and CK-MB levels with Child-Pugh and MELD scores in cirrhosis. These analyses were performed in the groups with and without decompensating events. Traditionally, CK-MB is helpful for estimating the infarct size in acute myocardial infarction and is highly specific to heart tissue [55, 56] while CK is used for assessing myocardial damage in acute myocardial infarction [57]. None of them is a good indicator of cardiac volume overload. Our study suggested that CK and CK-MB levels did not correlate with the severity of cirrhosis.

4.4. LDH

LDH, a cytoplasmic enzyme, exists in a wide range of tissues and is elevated when cells are damaged. LDH is not specific for the diagnosis of a disease. There are five types of serum LDH isoenzymes. Among them, LDH1 is mainly derived from the heart and LDH5 from the liver [58]. However, LDH5 have lower specificity and sensitivity than ALT for diagnosing and evaluating liver diseases [59]. LDH significantly correlated with Child-Pugh and MELD scores in cirrhotic patients. However, there was no significant difference in LDH levels between cirrhotic patients with and without decompensation. These results indicate that LDH might not be sensitive to early cardiac dysfunction caused by cirrhosis.

4.5. Limitations

First, the number of patients with ACLF was small in our cohort and the relationship between serum cardiac markers and ACLF needs further clarification. Second, a reasonable and convenient approach for quantifying blood loss volume during acute gastrointestinal hemorrhage and volume of ascites was unavailable. Third, healthy controls may make the results more comprehensive. Further studies should further consider the effects of the severity of such decompensating events on the long-term prognosis.

5. Conclusion

An elevated NT-pro BNP level might be useful to identify the cardiac volume overload caused by acute decompensating events in advanced cirrhosis. Additionally, the hs-cTnT level was elevated in cirrhosis with acute decompensating events.

Data Availability

The data used to support the findings of this study are available from the corresponding author upon reasonable request.

Disclosure

The abstract was published in the Asian Pacific Association for the Study of the Liver (APASL) 2020 Conference as a poster presentation. Please see the following link: https://link.springer.com/content/pdf/10.1007/s12072-020-10030-4.pdf.

Conflicts of Interest

The authors declare that they have no conflicts of interest.

Authors’ Contributions

Miaomiao Li reviewed the literature, wrote the study protocol, collected the data, performed the statistical analyses, and drafted the manuscript; Zeqi Guo, Dan Zhang, Xiangbo Xu, Fernando Gomes Romeiro, Andrea Mancuso, Jingqiao Zhang, Ruirui Feng, Xinmiao Zhou, and Cen Hong collected the data, checked the data, and gave critical comments; Xingshun Qi conceived the study, reviewed the literature, wrote the study protocol, treated the patients, checked the data, gave critical comments, and revised the manuscript. All authors have made an intellectual contribution to the manuscript and approved the submission. Miaomiao Li, Zeqi Guo, Dan Zhang, and Xiangbo Xu are co-first authors.

Acknowledgments

We would like to appreciate our study team for setting up and updating the prospective database, including Wenchun Bao, Feifei Hou, Zeqi Guo, Jingqiao Zhang, Xinmiao Zhou, Miaomiao Li, Ruirui Feng, Cen Hong, and Shixue Xu, of whom all had worked for our study group of establishing and updating this database, which prospectively recorded the patients treated by Dr. Xingshun Qi. The study was partially supported by the Science and Technology Project Foundation of Shenyang (19-112-4-005).

Supplementary Materials

Supplementary Table 1: a table showing partial correlation analysis of the hs-cTnT level in cirrhotic patients, cirrhotic patients with and without decompensation using value, correlation coefficient parameter. Supplementary Table 2: a table showing partial correlation analysis of the CK level in cirrhotic patients using value, correlation coefficient parameter. Supplementary Table 3: a table showing partial correlation analysis of the CK-MB level in cirrhotic patients using value, correlation coefficient parameter. Supplementary Table 4: a table showing partial correlation analysis of the LDH level in cirrhotic patients using value, correlation coefficient parameter. Supplementary Table 5: a table showing multivariate linear regression analysis of factors, such as age, gender, acute decompensation, ascites, acute gastrointestinal hemorrhage, and ACLF, associated with the hs-cTnT level in cirrhotic patients using value, -coefficient parameter. Supplementary Table 6: a table showing multivariate linear regression analysis of factors, such as age, gender, acute decompensation, ascites, acute gastrointestinal hemorrhage, and ACLF, associated with CK, CK-MB, and LDH levels in cirrhotic patients using value, -coefficient parameter. (Supplementary Materials)

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