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Research Article
Revised

Endothelin-1 as predictor of major adverse cardiovascular events in chronic coronary syndrome patients undergoing coronary intervention

[version 2; peer review: 1 approved with reservations, 1 not approved]
PUBLISHED 06 Jul 2023
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Abstract

Background: Major adverse cardiovascular events (MACE) are predicted to be low in chronic coronary syndrome (CCS) patients who have undergone percutaneous coronary intervention (PCI). Endothelin-1 has been considered a pro inflammatory biomarker and suggested as a novel prognostic indicator in CCS. The objective of this research was to prove endothelin- 1 as predictor of MACE within 1-year evaluation in CCS patients undergoing PCI.
Methods: This research was an analytic observational study with a cohort design. The participants were CCS patients who had undergone PCI. Endotelin-1 levels were checked before the patient underwent PCI. Occurrences of MACE were observed within 1 year. The comparison between normally distributed continuous data was performed with a T-test, and the Mann–Whitney test was used for not normally distributed data. A comparison between categorical data was performed with the Chi-square test. The cut-off point of endothelin-1 levels to predict MACE was analyzed by receiver operating characteristics (ROC).
Results: Participants in this study were 63 patients. Six patients experienced MACE within 1 year (9.5%) and 57 patients were included in the non-MACE group (90.5%). Mann Whitney T test showed there were significance differences in endothelin-1 levels from the two groups (p=0.022). The ROC curve showed cut off point the endothelin-1 is 4.07 ng/dl with a sensitivity of 83.3%, specificity of 75.4% and accuracy of 76.2% for the occurrence of MACE. Based on the area under curve (AUC) value and the accuracy of this study, endothelin-1 was able to detect MACE within 1 year of follow-up.
Conclusions: Endothelin-1 can be used as predictor of MACE within 1-year evaluation in CCS patients undergoing coronary intervention.

Keywords

endothelin-1, major adverse cardiovascular events, chronic coronary syndrome, coronary intervention

Revised Amendments from Version 1

In this new version, we added some additional points include: 
1. Adding sensitivity, specificity, and accuracy to predicts the occurrence of MACE
2. None of the patients in our study had chronic total occlusion (CTO)
3. Adding additional rows in Table 2 about comparison of LVEF in the MACE (+) and (-) groups. No significant difference between each group.

See the authors' detailed response to the review by Ahmed Shawky Elserafy
See the authors' detailed response to the review by Josip A Borovac

Introduction

Coronary heart disease (CHD) is a type of heart disease caused by the narrowing of the coronary arteries due to the atherosclerosis process. CHD can be divided into acute coronary syndrome (ACS) and chronic coronary syndrome (CCS).13 The diagnosis of CCS includes identification of risk factors for atherosclerosis, clinical evaluation, and supporting examinations.4,5

Endothelin-1 is derived from endothelial cells and several studies have reported its associated with endothelial dysfunction.68 Endothelial dysfunction has been reported as an atherosclerotic risk factor associated with future cardiovascular events,911 and therefore has been considered a pro inflammatory factor1214 and suggested as a novel prognostic indicator in ACS. However, its role in predicting cardiovascular events in stable coronary artery disease is unclear.1517 Endothelin-1 in the cardiovascular system is produced not only by vascular endothelial cells but also by vascular smooth muscle cells, cardiomyocytes, and fibroblasts.1820 Levels of endothelin-1 in blood plasma are very low under normal conditions, but the levels increase 100 times higher when the vascular wall shows increased cellular activity.2123 Endothelin-1 is a potent endogenous vasoconstrictor produced primarily by the vascular endothelium.2426 As a vasoconstrictor it contributes to increased tone in atherosclerotic coronary arteries and is involved in endothelial dysfunction, inflammation, and vascular remodeling.2729

A meta-analysis by Windecker et al. reported a reduction in mortality and incidence of acute myocardial infarction (AMI) with revascularization vs. medical therapy alone, in CCS patients when revascularization was performed with a coronary artery bypass graft (CABG) or a new generation of drug-eluting stent (DES) instead of the earlier bare metal stent (BMS) or balloon angioplasty alone.30 In patients with stable coronary artery disease, an initial fractional flow reserve (FFR)-guided PCI strategy was associated with a significantly lower rate of the primary composite end point of death, myocardial infarction, or urgent revascularization at five years than medical therapy alone. Patients without hemodynamically significant stenosis had a favorable long-term outcome with medical therapy alone.31

Methods

Ethics and consent

The protocol of the research was approved by the Medical and Health Research Ethics Committee of Dr. Moewardi Hospital Surakarta Indonesia No. 71/II/HREC/2021 on November 12, 2021. Participants provided signed informed consent to participate.

Participants

The design of the research was a prospective cohort study conducted in December 2021 – December 2022. The population were patients diagnosed with chronic coronary syndrome (CCS) who underwent cardiac catheterization (PCI) and were admitted in the intensive cardiovascular care unit (ICVCU) and cardiology ward of Dr. Moewardi Hospital, Surakarta, Indonesia. This study recruited 63 patients, consisting of 46 (73%) male patients and 17 (27%) female patients. We included subjects with a diagnosis of chronic coronary syndrome aged between 30 and 75 years old. We excluded subjects with acute myocardial infarction (AMI), previous history of PCI, severe heart valve abnormalities, history of chronic heart failure with New York Heart Association (NYHA) class ≥II, chronic renal failure, hepatic cirrhosis, and malignancy; with concomitant infection and sepsis; with concomitant acute stroke and acute inflammatory state (such as acute arthritis and pericarditis) during hospitalization; and acute heart failure. All subjects gave signed informed consent to participate in the study.

Procedure

Upon admission, before the patient underwent catheterization, a peripheral antecubital venous blood sample was obtained from each subject during the supine position. The blood sample was centrifuged at 4000 r.p.m. for 20 minutes and stored at −80°C in a freezer until analysis for endothelin-1 measurement. Endothelin-1 was detected and quantified with endothelin-1 immunoassay Quantikine® ELISA kit (R&D Systems, Minneapolis, USA) according to manufacturer procedure instructions (CV%: 23). The ELISA method was performed once by a skilled technician in the clinical pathology laboratory at Dr. Moewardi Hospital Surakarta Indonesia.

The subjects’ clinical data were collected during hospitalization. The treatments for subjects was at the discretion of attending cardiologists, without any interference of this research. Subjects were observed from admission until one year after hospital discharge for the occurrence of major adverse cardiac events (MACE). After the patient was discharged from the hospital, they are asked to carry out routine check-ins every month (if there are no complaints), or immediately check-in if there are complaints. If it is time for a check-in and the patient does not attend, they will be contacted by telephone or if necessary, a visit to the patient's home is made. The adverse cardiac event was the composite of cardiac death, acute heart failure, cardiogenic shock, reinfarction, and resuscitated ventricular arrhythmia. Cardiac death was fatal due to cardiac disease. Acute heart failure was defined as the occurrence of signs/symptoms of congestion and the use of intravenous diuretics. Cardiogenic shock was defined as the signs of reduced peripheral perfusion and the use of vasopressors drugs. Reinfarction was defined as the recurrent chest pain, recurrent ST-segment elevation, and an elevation of cardiac enzymes. Resuscitated ventricular arrhythmia was the return of spontaneous circulation after resuscitation for lethal arrhythmias.

Analysis

For statistical analysis, SPSS 26.0 for Windows (SPSS Inc., Chicago, IL, USA) was used. The subjects were divided into two groups based on the presence of adverse cardiac events. The normal distribution was tested with the Kolmogorov-Smirnov test. The comparison between normally distributed continuous data was performed with Student's T-test, while the Mann–Whitney test was used for not normally distributed continuous data. A comparison between categorical data was performed with the Chi-square test. A receiver operating characteristic (ROC) curve was designed to determine the cut-off point of endothelin-1 level to predict adverse cardiac events. A univariate and multivariable analysis with logistic regression test were performed to determine the independent predictor of an adverse cardiac event. A p value < 0.05 was set as statistical significance.

Results

This study was conducted in the emergency room, polyclinic, intensive cardiovascular care unit (ICCU), and cardiac care ward, clinical pathology laboratory, and cardiac catheterisation laboratory hospital. 63 samples from patients with CCS were obtained. The 63 patients were then monitored for one year for the development of major adverse cardiovascular events (MACE). None of the patients had chronic total occlusion (CTO). The results of this study listed in the Table 1.

Table 1. Variable description of research characteristics.

VariableParameters
N (%)Mean ± SD
Age (years)56.73 ± 8.87
Sex
Male (n)46 (73.0%)
Female (n)17 (27.0%)
Hypertension (n)23 (36.5%)
DM (n)19 (30.2%)
Smoking (n)13 (20.6%)
Dyslipidemia (n)19 (30.2%)
History of CHD (n)28 (44.4%)
Clinical condition
BMI (kg/m2)24.11 ± 3.81
Heart Rate (x/min)73.25 ± 12.52
Laboratory
Hemoglobin (g/dL)13.77  ± 1.68
Leukocytes (mcg/L)8.37  ± 2.18
Platelets (mcg/L)270.44 ± 78.81
Urea (mg/dL)30.40 ± 12.09
Creatinine (mg/dL)1.15 ± 0.32
eGFR (ml/min)72.86 ± 21.47
HbA1C (%)6.78 ± 1.68
Fasting Blood Sugar (mg/dL)109.21 ± 42.49
Blood sugar 2 hours post prandial (mg/dL)140.59 ± 56.19
Uric Acid (mg/dL)6.83 ± 1.87
Cholesterol (mg/dL)158.04 ± 45.79
LDL (mg/dL)103.92 ± 35.05
HDL (mg/dL)39.02 ± 9.73
Triglycerides (mg/dL)152.32 ± 67.47
Echocardiographic parameters
LVEF (%)48.30  ± 4.59
TAPSE (cm)2.07 ± 0.27
VariableParameters
N (%)Mean ± SD
Coronary angiography results
Left Main0 (0.0%)
1 Vessel28 (44.4%)
2 Vessel16 (25.4%)
3 Vessel19 (30.2%)

For variables related to coronary angiography results, 28 (44.4%) persons involved one coronary vessel, 16 (25.4%) persons involved two vessels, and 19 (30,2%) person involved three vessels. None of the patients has chronic total occlusion (OTC). The characteristic variable descriptions and coronary angiography are presented in Table 2.

Table 2. Variable description of research characteristics.

Quantitative variablesMACE (-)MACE (+)Prob.
Mean/nSD/%Mean/nSD/%
Demographics
Age (years)a56.149.0062.335.160.104
Sexb1.00
Male4171.9%583.3%
Female1628.1%116.7%
BMI (kg/m2)a24.153.8923.733.650.799
Risk factors
Hypertensionb2035.1%350.0%0.660
DMb1628.1%350.0%0.355
Smokingb1322.8%00.0%0.33
Dyslipidemiab1933.3%00.0%0.166
Echocardiographic
LVEFa48.34.59495.040.65

a Independent t test (numerical data fulfils normality assumptions).

b Chi-squared test/Fisher exact test (nominal categorical data).

Of the 63 patients in the study, six patients experienced MACE within 1 year (9.5%), and 57 patients were included in the non-MACE group (90.5%). MACE occurred in the evaluation of six patients (9.5%), in the form of acute myocardial infarction, heart failure, and death in two (33.3%), one (16.6%), and three (50%) patients, respectively. In male patients who underwent MACE, two patients experienced AMI, one patient experienced heart failure, and two patients died. Only one female patient experienced MACE due to death. Two patients were not routinely monitored for evaluation, due to busyness of the patients, insurance issues, or geography

Endothelin-1 levels generally ranged from 2.15 pg/ml to 6.90 pg/ml, with a mean of 3.66 pg/ml and a standard deviation of 1.09 pg/ml (3.66 ± 1.09 pg/ml). In the non-MACE sample group, endothelin-1 levels ranged from 2.15 pg/ml to 6.90 pg/ml, with a mean of 3.59 pg/ml and a standard deviation of 1.09 pg/ml (3.59 ± 1.09 pg/ml). In the MACE sample group, endothelin-1 levels ranged from 3.52 pg/ml to 5.84 pg/ml, with a mean of 4.37 pg/ml and a standard deviation of 0.78 pg/ml (4.37 ± 0.78 pg/ml). The description and testing of endothelin-1 level variables are presented in Table 3.

Table 3. Relation of endothelin-1 level and MACE occurrences.

VariableMACE (-)MACE (+)P
MeanSDMeanSD
Endothelin-13.591.094.370.780.022*

* significant at the 5 percent significance level.

The calculation of endothelin-1 levels as a predictor of 1-year MACE variables was done by using the receiver operating characteristic (ROC) curve. The area under the curve (AUC) for the ROC curve on the incidence of MACE for the variable endothelin-1 level as a predictor was 0.785. The interpretation of the variable endothelin-1 level can detect the incidence of MACE well. Based on the ROC curve, the cut-off point value of the endothelin-1 level variable was 4.07ng/dl, and the occurrence of MACE can be detected from the endothelin-1 level variable with a sensitivity rate of 83.3% and a specificity rate of 75.4% and a diagnostic accuracy rate of 76.2%. The results of sensitivity, specificity, and diagnostic accuracy are presented in Table 4.

Table 4. Sensitivity, specificity, diagnostic accuracy relation of endothelin-1 level and MACE.

MACE 1 year
ExaminationAUCCutoffSensivitySpecifityAccuracy
Endothelin-10.7854.0783.3%75.4%76.2%

The relationship between endothelin-1 levels and 1-year MACE (cut-off point = 4,07) are presented in Table 5.

Table 5. Relation of endothelin-1 levels and 1-year MACE (cut-off point = 4.07).

VariableMace (+)Mace (-)p-value
n%n%
Endothelin-1>4.07 (high)583.31424.60.008**
<4.07 (low)116.74375.4
Total57100.06100.0

** Significant at 1% significance level.

The statistical test results of the relationship between endothelin-1 levels and MACE with a probability of p = 0.008 indicate that the relationship is significant at a 1% significance level (p 0.01). The odds ratio reached 15.36, with a 95% confidence interval of 1.65 142.84, indicating that the relation between endothelin-1 levels and MACE was truly significant (convincing). The ROC curve on MACE events for variable endothelin-1 levels as a predictor resulted in an AUC value of 0.785 with an accuracy rate of 76.5%. All of this demonstrates that endothelin-1 levels are a good predictor of MACE within a year.

Discussion

MACE or major adverse cardiovascular event is often used as a composite outcome of an observational study. Various definitions of MACE show different components in each study; some define MACE into three, four of five components.3234 From all studies, it can be concluded that the most common components are acute myocardial infarction, stroke, and death. In addition, there were 15 studies that included heart failure as a component of MACE.3537

Zhou's study included 3154 patients with stable CHD who were followed for 24 months. This study showed that endothelin-1 levels were associated with major cardiovascular events in CHD patients who were not revascularized. Endothelin-1 plays a prognostic role in stable CHD patients.3840 An increase in endothelin-1 levels caused vasoconstriction and decreased coronary blood flow, thus causing and exacerbating myocardial ischemia. Haug's study showed that endothelin-1 production increases in conditions where there are atherosclerotic plaques in the coronary arteries. Endothelin-1 release stimulates smooth muscle cell proliferation in a paracrine or autocrine manner, which may contribute to the development of coronary artery disease.4145

In our study, MACE occurred in six patients in the study sample. The low incidence of MACE could be due to several reasons. Firstly, the level of patient compliance with treatment was quite good at the 1-year follow-up. In addition, 63 patients underwent percutaneous coronary intervention (PCI). PCI is associated with a significant reduction in the primary composite risk of death, acute myocardial infarction, and urgent revascularization within five years, when compared with medical therapy alone.4651

In one retrospective cohort study, it was demonstrated that sex has an impact on subsequent adverse cardiovascular outcomes among patients over 60 years of age with atherothrombotic disease.52

Research by Hata J and Kiyohara Y, 2013 in Asia reported that adverse cardiovascular events including ACS, all strokes, vascular procedures, and death in hospital were significantly lower in female patients than in males, both with univariate and multivariate analysis. Traditional atherosclerotic risk factors are age, hypertension, dyslipidemia, diabetes mellitus, and smoking.53

In contrast to some previous meta-analyses, Zimmermann et al’s 2019 meta-analysis of 2400 subjects reported that reduced MACE was confirmed in patients undergoing PCI procedures, showing significant reductions in cardiac death and MI after a median follow-up 33 months with fractional flow reserve (FFR)-guided PCI vs. medical therapy (hazard ratio 0.74, 95% CI 0.56-0.989, P=0.041).54

The ROC curve on MACE events for variable endothelin-1 levels as a predictor resulted in an AUC value of 0.785 with an accuracy rate of 76.5% in our study, which showed that endothelin-1 can act as a predictor for major cardiovascular events within 1 year. Diagnostic test research will be improved if the AUC value is close to 1. Criteria for interpreting the AUC value are as follows: >0.5-0.6 = very weak, >0.6-0.7 = weak, >0.7-0.8 = moderate, >0.8-0.9 = good, >0.9-1 = very good. The following criteria are used to interpret the accuracy score categories: 50-60% is very weak, 60-70% is weak, 70-80% is medium, 80-90% is strong, and 90-100% is very strong.55 This can be interpreted to mean that endothelin-1 levels can detect the occurrence of MACE in patients with CCS after a 1-year follow-up.

The limitations of this study were that it was only conducted in one center, and two patients were not routinely monitored for evaluation, due to busyness of the patients, insurance issues, or geography. Thus, the follow-up of patients cannot be fully monitored properly. Another limitation of this study is the small sample size, which is clearly insufficient to accurately describe the situation.56,57

Conclusion

Endothelin-1 can be a predictor of major adverse cardiovascular events within 1 year in patients with CCS who had coronary intervention.

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Wasyanto T, Yasa A and Ayu N. Endothelin-1 as predictor of major adverse cardiovascular events in chronic coronary syndrome patients undergoing coronary intervention [version 2; peer review: 1 approved with reservations, 1 not approved]. F1000Research 2023, 12:342 (https://doi.org/10.12688/f1000research.130837.2)
NOTE: If applicable, it is important to ensure the information in square brackets after the title is included in all citations of this article.
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Key to Reviewer Statuses VIEW
ApprovedThe paper is scientifically sound in its current form and only minor, if any, improvements are suggested
Approved with reservations A number of small changes, sometimes more significant revisions are required to address specific details and improve the papers academic merit.
Not approvedFundamental flaws in the paper seriously undermine the findings and conclusions
Version 2
VERSION 2
PUBLISHED 06 Jul 2023
Revised
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Reviewer Report 18 Jul 2023
Josip A Borovac, University Hospital of Split, Split, Croatia 
Not Approved
VIEWS 8
The authors did try to address my concerns in their rebuttal letter, however, I do not think this was performed sufficiently. The paper still has significant limitations and ambiguities that raise a high publication concern.

This second ... Continue reading
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Borovac JA. Reviewer Report For: Endothelin-1 as predictor of major adverse cardiovascular events in chronic coronary syndrome patients undergoing coronary intervention [version 2; peer review: 1 approved with reservations, 1 not approved]. F1000Research 2023, 12:342 (https://doi.org/10.5256/f1000research.152526.r184679)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
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Reviewer Report 07 Jul 2023
Ahmed Shawky Elserafy, Ain Shams University, Cairo, Cairo Governorate, Egypt 
Approved with Reservations
VIEWS 9
Most of the comments provided by the reviewers were answered. However, the number of subjects and ... Continue reading
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HOW TO CITE THIS REPORT
Elserafy AS. Reviewer Report For: Endothelin-1 as predictor of major adverse cardiovascular events in chronic coronary syndrome patients undergoing coronary intervention [version 2; peer review: 1 approved with reservations, 1 not approved]. F1000Research 2023, 12:342 (https://doi.org/10.5256/f1000research.152526.r184678)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
  • Author Response 11 Jul 2023
    Trisulo Wasyanto, Department of Cardiology and Vascular Medicine, Sebelas Maret University, Dr Moewardi Hospital, Surakarta, 57126, Indonesia
    11 Jul 2023
    Author Response
    Thank you very much for the comments. In fact, our study already exceeded the minimum sample size required to make results statistically significant. Sample size was calculated using Open Epi ... Continue reading
COMMENTS ON THIS REPORT
  • Author Response 11 Jul 2023
    Trisulo Wasyanto, Department of Cardiology and Vascular Medicine, Sebelas Maret University, Dr Moewardi Hospital, Surakarta, 57126, Indonesia
    11 Jul 2023
    Author Response
    Thank you very much for the comments. In fact, our study already exceeded the minimum sample size required to make results statistically significant. Sample size was calculated using Open Epi ... Continue reading
Version 1
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PUBLISHED 28 Mar 2023
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Reviewer Report 26 Jun 2023
Josip A Borovac, University Hospital of Split, Split, Croatia 
Not Approved
VIEWS 20
  • In the Abstract section, authors present data on ROC curve and provide sensitivity and specificity info, however, they do not make explicit statement to what does this sensitivity and specificity refer to. It might be implicative this
... Continue reading
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Borovac JA. Reviewer Report For: Endothelin-1 as predictor of major adverse cardiovascular events in chronic coronary syndrome patients undergoing coronary intervention [version 2; peer review: 1 approved with reservations, 1 not approved]. F1000Research 2023, 12:342 (https://doi.org/10.5256/f1000research.143621.r181207)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
  • Author Response 06 Jul 2023
    Trisulo Wasyanto, Department of Cardiology and Vascular Medicine, Sebelas Maret University, Dr Moewardi Hospital, Surakarta, 57126, Indonesia
    06 Jul 2023
    Author Response
    Responses (2)
    AUTHOR RESPONSE
    Comment 1
    In the Abstract section, authors present data on ROC curve and provide sensitivity and specificity info, however, they do not make explicit statement to what ... Continue reading
COMMENTS ON THIS REPORT
  • Author Response 06 Jul 2023
    Trisulo Wasyanto, Department of Cardiology and Vascular Medicine, Sebelas Maret University, Dr Moewardi Hospital, Surakarta, 57126, Indonesia
    06 Jul 2023
    Author Response
    Responses (2)
    AUTHOR RESPONSE
    Comment 1
    In the Abstract section, authors present data on ROC curve and provide sensitivity and specificity info, however, they do not make explicit statement to what ... Continue reading
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21
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Reviewer Report 09 Jun 2023
Ahmed Shawky Elserafy, Ain Shams University, Cairo, Cairo Governorate, Egypt 
Not Approved
VIEWS 21
Very nice manuscript actually and a sound hypothesis.

The introduction is clear; however, I would remove the word “earlier DES (bare metal stent)” and just keep it bare metal stents.

The methods were constructive ... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Elserafy AS. Reviewer Report For: Endothelin-1 as predictor of major adverse cardiovascular events in chronic coronary syndrome patients undergoing coronary intervention [version 2; peer review: 1 approved with reservations, 1 not approved]. F1000Research 2023, 12:342 (https://doi.org/10.5256/f1000research.143621.r174144)
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
  • Author Response 06 Jul 2023
    Trisulo Wasyanto, Department of Cardiology and Vascular Medicine, Sebelas Maret University, Dr Moewardi Hospital, Surakarta, 57126, Indonesia
    06 Jul 2023
    Author Response
    Responses (1)
    AUTHOR RESPONSE

    Comment 1
    The introduction is clear; however, I would remove the word “earlier DES (bare metal stent)” and just keep it bare metal stents.

    Response ... Continue reading
COMMENTS ON THIS REPORT
  • Author Response 06 Jul 2023
    Trisulo Wasyanto, Department of Cardiology and Vascular Medicine, Sebelas Maret University, Dr Moewardi Hospital, Surakarta, 57126, Indonesia
    06 Jul 2023
    Author Response
    Responses (1)
    AUTHOR RESPONSE

    Comment 1
    The introduction is clear; however, I would remove the word “earlier DES (bare metal stent)” and just keep it bare metal stents.

    Response ... Continue reading

Comments on this article Comments (0)

Version 2
VERSION 2 PUBLISHED 28 Mar 2023
Comment
Alongside their report, reviewers assign a status to the article:
Approved - the paper is scientifically sound in its current form and only minor, if any, improvements are suggested
Approved with reservations - A number of small changes, sometimes more significant revisions are required to address specific details and improve the papers academic merit.
Not approved - fundamental flaws in the paper seriously undermine the findings and conclusions
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