sST2 Predicts Short Term Therapy Success in Patients with Therapy Resistant Hypertension after Renal Sympathetic Denervation

Round 1

Reviewer 1 Report

An interesting study showing the role of sST2 as a short come predictor of in patients with therapy resistant hypertension after renal sympathetic denervation.

 

To my opinion, the correlation with other biochemical parameters including TnI and natriuretic peptides (BNP or NTproBNP) and multifactorial analysis (comparison with BMI, renal clearance, renal function and cardiovascular function) will extend scientific merit.

Author Response

Dear Editor!
Dear Reviewer #1:

We are very grateful for the in-depth review of our manuscript and your favorable assessment of our work. Please find attached our revised version of the manuscript. We have substantially improved all major sections of the manuscript according to the reviewers’ esteemed suggestions and points of criticism. Please find below a point-by-point response invorporating all concerns and suggestions by all reviewers.
We do sincerely hope that in its present form you will find the manuscript acceptable for publication.

Sincerely yours,
Albert Topf

Reviewer 1

Comment 1: An interesting study showing the role of sST2 as a short come predictor of in patients with therapy resistant hypertension after renal sympathetic denervation. To my opinion, the correlation with other biochemical parameters including TnI and natriuretic peptides (BNP or NTproBNP) and multifactorial analysis (comparison with BMI, renal clearance, renal function and cardiovascular function) will extend scientific merit. 

Response 1: We thank the reviewer for his/her kind remarks and the appreciation of our work. A correlation analysis of patient characteristics, having an influence on sST-2 levels, was added in the revised manuscript. (page 5, line 176). In a multifactorial analysis of the parameters suggested (BMI, renal clearance, renal function, cardiovascular function), the presence of diabetes and serum LDL levels revealed a statistical significant influence on postprocedural blood pressure reduction. (page 4, line 15)

Author Response File: Author Response.pdf

Reviewer 2 Report

sST2 represents a clinically relevant biomarker reflecting pathophysiological processes and contributing predictive information in the setting of several cardiovascular diseases, like sudden cardiac death, heart failure, and left ventricular systolic dysfunction (e.g. Pascual-Figal DA, Ordoñez-Llanos J, Tornel PL, et al. Soluble ST2 for predicting sudden cardiac death in patients with chronic heart failure and left ventricular systolic dysfunction. J Am Coll Cardiol. 2009;54(23):2174-2179. doi:10.1016/j.jacc.2009.07.041).

In this interesting study, Authors showed predictive value of the change in the soluble form of ST2 (sST2) receptor for Interleukin-1 following renal denervation procedure in a group of 54 consecutive patients with essential hypertension. The study group was highly pre-selected, thus study results cannot be extrapolated to broad spectrum of patients with cardiovascular disease.

The most important finding is that the reduction in either sST2, SBP and left ventricle mass (LVM) are observed at 1 and 3 months following renal denervation procedure. Authors wrote: ‘Consistent with a reduction in systolic blood pressure, a steady decrease in calculated LV mass was observed during follow-up. At three months post intervention, this reduction reached the level of statistical significance (LVM 246.4±82.4 g at baseline, 216.7±60.6 178g at one month, p=0.163 versus baseline, 180.9±66.8 g at three months, p=0.010 versus baseline; Figure 2 A). These findings may indicate successful cardiac reverse remodeling.’

However, it is not clear from the present study, whether there is relationship between the degree of  sST2 change following renal denervation and the degree of SBP, DBP and LVM reduction.

So, I suggest to provide correlations between the degree of LVM reduction and the degree of SBP and DBP reduction, as well as sTS2 change and the degree of reduction in SBP, DBP, and LVM. Only then, Authors conclusions can be justified (‘significant decrease of sST2 levels after three months, indicating sST2 to be involved in remodeling processes after RSD’).

Authors may update Figure 3 and Figure 4 with correlations between changes in sST2, BP, and LVM.

In vast number of publications, the BP reduction and LVM reduction are independent from each other (e.g. Rzeźnik D, et al. Effect of renal artery revascularization on left ventricular hypertrophy, diastolic function, blood pressure, and the one-year outcome. J Vasc Surg. 2011, 53, 692-697.]. And Bamaiyi AJ, et al. Limited contribution of left ventricular mass and remodelling to the impact of blood pressure on diastolic function in a community sample. J Hypertens. 2019;37(6):1191-1199.]

This issue should be addressed in Discussion

Authors should also discuss their findings in the context of baseline SBP and DBP values. As evidenced from the former studies, higher baseline SBP and DBP is associated with greater favorable response in terms of SBP and DBP reduction. Authors stated that: ‘Compared to baseline (SBP 175.6±23.3 mmHg), a significant reduction in office systolic BP was observed at one month (SBP 157.7±20 mmHg; p<0.001) and three months 167 (SBP 157.2±24.1 mmHg; p=0.01) after RSD (Figure 1)’

however there was only trend to significance for DBP which was: ‘94.3±12.2 mmHg at baseline versus 89.8±14.3 169 mmHg at one month, p=0.254, and 87.9±16.4 mmHg at three months, p=0.084.’

This favors opinion that baseline BP values should be markedly elevated before renal denervation can be considered as therapeutic option. This is also supported by other procedures engaging renal arteries, like angioplasty and stenting for renal artery stenosis (e.g. Rosławiecka A, et al. Determinants of long-term outcome in patients after percutaneous stent-assisted intervention for renal artery steno-occlusive atherosclerotic disease. Pol Arch Intern Med. 2019;129(11):747-760.), but it is also emphasized by studies with renal denervation (e.g. Tsioufis C, et al. Blood pressure response to catheter-based renal sympathetic denervation in severe resistant hypertension: data from the Greek Renal Denervation Registry Clin Res Cardiol. 2017;106(5):322-330, or Juknevičius V, Berūkštis A, Juknevičienė R, Jasiūnas E, Šerpytis P, Laucevičius A. Long-Term Effects of Renal Artery Denervation. Medicina (Kaunas). 2021;57(7):662.

Please address this issue in Discussion. What, according to Authors, baseline SBP and DBP values justify renal denervation procedure.

Author Response

Dear Editor!

Dear Reviewer #2:

 

We are very grateful for the in-depth review of our manuscript and your favorable assessment of our work. Please find attached our revised version of the manuscript. We have substantially improved all major sections of the manuscript according to the reviewers’ esteemed suggestions and points of criticism. Please find below a point-by-point response invorporating all concerns and suggestions by all reviewers.

We do sincerely hope that in its present form you will find the manuscript acceptable for publication.

Sincerely yours,

Albert Topf

 

Reviewer 2

Comment 1:  sST2 represents a clinically relevant biomarker reflecting pathophysiological processes and contributing predictive information in the setting of several cardiovascular diseases, like sudden cardiac death, heart failure, and left ventricular systolic dysfunction (e.g. Pascual-Figal DA, Ordoñez-Llanos J, Tornel PL, et al. Soluble ST2 for predicting sudden cardiac death in patients with chronic heart failure and left ventricular systolic dysfunction. J Am Coll Cardiol. 2009;54(23):2174-2179. doi:10.1016/j.jacc.2009.07.041).

 

In this interesting study, Authors showed predictive value of the change in the soluble form of ST2 (sST2) receptor for Interleukin-1 following renal denervation procedure in a group of 54 consecutive patients with essential hypertension. The study group was highly pre-selected, thus study results cannot be extrapolated to broad spectrum of patients with cardiovascular disease.

Response 1: We thank the reviewer for his/her kind remarks and the appreciation of our work. In accordance to previous or ongoing studies on renal denervation, a pre-selected study group with therapy refractory hypertension was enrolled in our study.[i] This important information was included in the methods and commented on in the limitations section accordingly. (page 2, line 95; page 10, line 12)

 

Comment 2: The most important finding is that the reduction in either sST2, SBP and left ventricle mass (LVM) are observed at 1 and 3 months following renal denervation procedure. Authors wrote: ‘Consistent with a reduction in systolic blood pressure, a steady decrease in calculated LV mass was observed during follow-up. At three months post intervention, this reduction reached the level of statistical significance (LVM 246.4±82.4 g at baseline, 216.7±60.6 178g at one month, p=0.163 versus baseline, 180.9±66.8 g at three months, p=0.010 versus baseline; Figure 2 A). These findings may indicate successful cardiac reverse remodeling.’

However, it is not clear from the present study, whether there is relationship between the degree of sST2 change following renal denervation and the degree of SBP, DBP and LVM reduction.

So, I suggest to provide correlations between the degree of LVM reduction and the degree of SBP and DBP reduction, as well as sTS2 change and the degree of reduction in SBP, DBP, and LVM. Only then, Authors conclusions can be justified (‘significant decrease of sST2 levels after three months, indicating sST2 to be involved in remodeling processes after RSD’).

Response 2: As stated, in parallel with the reduction of systolic blood pressure after one month a significant reduction of LVM after one month was observed (r=0.403, p=0.015). Although a numerical trend towards a correlation between the decrease of sST-2 levels at one month and the LV mass reduction at one month was present, this did not reach the level of statistic significance (r=0.660, p=0.053). Therefore, a statistically significant correlation between sST2 and LV mass reduction could not be shown. An association between blood pressure lowering and consecutive LV mass reduction, however, was present. Therefore, baseline levels of sST-2 could be shown to predict postprocedural blood pressure reduction after one month.

Comment 3: In vast number of publications, the BP reduction and LVM reduction are independent from each other (e.g. Rzeźnik D, et al. Effect of renal artery revascularization on left ventricular hypertrophy, diastolic function, blood pressure, and the one-year outcome. J Vasc Surg. 2011, 53, 692-697.]. And Bamaiyi AJ, et al. Limited contribution of left ventricular mass and remodelling to the impact of blood pressure on diastolic function in a community sample. J Hypertens. 2019;37(6):1191-1199.]

This issue should be addressed in Discussion

Response 3: We thank the reviewer for this important comment considering the presence of controversial results regarding the correlation between LVM reduction and BP reduction following renal denervation. In the aforementioned literature, a significant degree of LVM reduction could not be observed after blood pressure reduction. However, there is high ranking literature confirming the presence of LVM reduction following blood pressure reduction after renal denervation.[ii] This issue was added to our discussion. (page 8 line 243 and page 7 line 216)

Comment 4: Authors should also discuss their findings in the context of baseline SBP and DBP values. As evidenced from the former studies, higher baseline SBP and DBP is associated with greater favorable response in terms of SBP and DBP reduction. Authors stated that: ‘Compared to baseline (SBP 175.6±23.3 mmHg), a significant reduction in office systolic BP was observed at one month (SBP 157.7±20 mmHg; p<0.001) and three months 167 (SBP 157.2±24.1 mmHg; p=0.01) after RSD (Figure 1)’

however there was only trend to significance for DBP which was: ‘94.3±12.2 mmHg at baseline versus 89.8±14.3 169 mmHg at one month, p=0.254, and 87.9±16.4 mmHg at three months, p=0.084.’

This favors opinion that baseline BP values should be markedly elevated before renal denervation can be considered as therapeutic option. This is also supported by other procedures engaging renal arteries, like angioplasty and stenting for renal artery stenosis (e.g. Rosławiecka A, et al. Determinants of long-term outcome in patients after percutaneous stent-assisted intervention for renal artery steno-occlusive atherosclerotic disease. Pol Arch Intern Med. 2019;129(11):747-760.), but it is also emphasized by studies with renal denervation (e.g. Tsioufis C, et al. Blood pressure response to catheter-based renal sympathetic denervation in severe resistant hypertension: data from the Greek Renal Denervation Registry Clin Res Cardiol. 2017;106(5):322-330, or Juknevičius V, Berūkštis A, Juknevičienė R, Jasiūnas E, Šerpytis P, Laucevičius A. Long-Term Effects of Renal Artery Denervation. Medicina (Kaunas). 2021;57(7):662.

Please address this issue in Discussion. What, according to Authors, baseline SBP and DBP values justify renal denervation procedure.

Response 4: We thank the reviewer for this important comment. Our findings are in accordance with results from multiple publications, that excessive baseline hypertension is a predictor of renal denervation success (and also correlates with the degree of blood pressure reduction in conventional medial antihypertensive therapy). It is a question of debate, if this condition is caused by a greater baseline excess of sympathetic overdrive in patients with higher baseline BP values and/or a “regression to the mean” effect following denervation. According to the ESC guidelines of 2018, device based antihypertensive therapies are not recommended for the routine treatment of hypertension, unless in the context of clinical studies and RCTs, until further evidence regarding their safety and efficacy becomes available. Therefore, therapy refractory hypertension was the most common inclusion criteria. Evidenced from former studies, higher baseline SBP and DBP is associated with a better therapy response. Similar effects were observed in patients receiving conventional medical antihypertensive therapy and those undergoing renal angioplasty. In most previous or ongoing studies, a RH with a systolic blood pressure of 160mmHg or more was required as an inclusion criteria.¹ An additional passage was added to the discussion as requested (Page 7, line 216).

 

[i] https://clinicaltrials.gov/ct2/show/NCT00664638

[ii] Brandt MC, Mahfoud F, Reda S, Schirmer SH, Erdmann E, Böhm M, Hoppe UC. Renal sympathetic denervation reduces left ventricular hypertrophy and improves cardiac function in patients with resistant hypertension. J Am Coll Cardiol. 2012 Mar 6;59(10):901-9. doi: 10.1016/j.jacc.2011.11.034. PMID: 22381425.

Author Response File: Author Response.pdf

Reviewer 3 Report

Topf et al. explored how sST2 Predicts Short Term Outcome in Patients with Therapy Resistant Hypertension after Renal Sympathetic Denervation in a small observational study. 

 

Overall, a small number of participants made correlation analyses performed in the study virtually irrelevant (n of people who went through all parts of study was only 20). Moreover, regression analysis could not be performed due to the same reasons, hence, multiple confounders may be present. Finally, the inferences from the present results are not valid. For instance, based on correlation of sST2 after one month and SBP, the authors concluded that sST2 might be a potential predictor of early intervention success of RSD. To reach such conclusions the authors should have performed serial measurements. Why didn’t the authors compare SBP with sST2 at the onset of the study?

 

The introduction section should be substantially shortened. The role of introduction is to appropriately address the problem and define the aim of the study to the readers. In addition, the aim of the study may be defined more appropriately.

 

Why was T1DM an exclusion criteria and T2DM wasn’t? Please explain.

 

Was normality of data tested? The authors performed Mann Whitney U test implying non-normal distribution but presented data as mean +/- SD and conducted Pearson's analysis as if data were normal. Please revise.

 

It is very important to highlight the number of people having T2DM, and make comparisons taking it into account, as T2DM can be a significant confounding factor in the present research. Namely, Fousteris et al. demonstrated higher plasma concentrations of sST2 among patients with DM type 2 in comparison to healthy controls [Fousteris E, Melidonis A, Panoutsopoulos G, Tzirogiannis K, Foussas S, Theodosis-Georgilas A, Tzerefos S, Matsagos S, Boutati E, Economopoulos T, Dimitriadis G, Raptis S. Toll/interleukin-1 receptor member ST2 exhibits higher soluble levels in type 2 diabetes, especially when accompanied with left ventricular diastolic dysfunction. Cardiovasc Diabetol. 2011;10:101]. In addition, even higher levels of sST2 have been observed in patients with both T2DM and left ventricular diastolic dysfunction, an early finding in diabetic cardiomyopathy [Kumric M, Ticinovic Kurir T, Borovac JA, Bozic J. Role of novel biomarkers in diabetic cardiomyopathy. World J Diabetes 2021; 12(6): 685-705].

 

Table 1. make it a two column table with data presented as n (%) or mean and SD.

 

Figures. Specify the test which was conducted in the footnote. Apply to all figures.

 

Remove speculations such as “indicating potentially lower sST2-2 levels at baseline may predict successful short-term outcomes at one month after intervention.” from the results section to the discussion.

 

Line 89 – please define HT

Author Response

Dear Editor!

Dear Reviewer #3:

We are very grateful for the in-depth review of our manuscript and your favorable assessment of our work. Please find attached our revised version of the manuscript. We have substantially improved all major sections of the manuscript according to the reviewers’ esteemed suggestions and points of criticism. Please find below a point-by-point response invorporating all concerns and suggestions by all reviewers.

We do sincerely hope that in its present form you will find the manuscript acceptable for publication.

Sincerely yours,

Albert Topf

 

Reviewer 3

Comment 1: Topf et al. explored how sST2 Predicts Short Term Outcome in Patients with Therapy Resistant Hypertension after Renal Sympathetic Denervation in a small observational study.

Overall, a small number of participants made correlation analyses performed in the study virtually irrelevant (n of people who went through all parts of study was only 20). Moreover, regression analysis could not be performed due to the same reasons, hence, multiple confounders may be present. Finally, the inferences from the present results are not valid. For instance, based on correlation of sST2 after one month and SBP, the authors concluded that sST2 might be a potential predictor of early intervention success of RSD. To reach such conclusions the authors should have performed serial measurements. Why didn’t the authors compare SBP with sST2 at the onset of the study?

Response 1: We thank the reviewer for this important comment. In Figure 3, we have already shown the significant correlation of baseline sST-2 levels with systolic BP one month after RSD. To avoid misunderstandings, baseline sST-2 measurement was more precisely explained in the methods section. (page 2, line 94)

Comment 2: The introduction section should be substantially shortened. The role of introduction is to appropriately address the problem and define the aim of the study to the readers. In addition, the aim of the study may be defined more appropriately.

Response 2: We thank the reviewer for this important comment. The introduction was re-written more concisely and structuredly.

Comment 3: Why was T1DM an exclusion criteria and T2DM wasn’t? Please explain.

Response 3: In accordance with previous and current studies in renal denervation, a pre-selected study group was enrolled in our study.¹ This important information was included in the methods, the discussion and the limitations. (page 2, line 95; page 10, line 12)

Comment 4: Was normality of data tested? The authors performed Mann Whitney U test implying non-normal distribution but presented data as mean +/- SD and conducted Pearson's analysis as if data were normal. Please revise.

Response 4: We thank the reviewer for the productive evaluation of our manuscript. Due to better readability, the part explaining the statistical methods was rewritten. We could demonstrate a normal distribution of the parameters studied with a Kolmogorov-Smirnov test, therefore we could change to a student’s t test for the assessment of statistical significance (page 3, line 130). For completeness sake we would like to add that the non-parametric Mann-Whitney U test would have been the more critical test in terms of statistic significance.

Comment 5: It is very important to highlight the number of people having T2DM, and make comparisons taking it into account, as T2DM can be a significant confounding factor in the present research. Namely, Fousteris et al. demonstrated higher plasma concentrations of sST2 among patients with DM type 2 in comparison to healthy controls [Fousteris E, Melidonis A, Panoutsopoulos G, Tzirogiannis K, Foussas S, Theodosis-Georgilas A, Tzerefos S, Matsagos S, Boutati E, Economopoulos T, Dimitriadis G, Raptis S. Toll/interleukin-1 receptor member ST2 exhibits higher soluble levels in type 2 diabetes, especially when accompanied with left ventricular diastolic dysfunction. Cardiovasc Diabetol. 2011;10:101]. In addition, even higher levels of sST2 have been observed in patients with both T2DM and left ventricular diastolic dysfunction, an early finding in diabetic cardiomyopathy [Kumric M, Ticinovic Kurir T, Borovac JA, Bozic J. Role of novel biomarkers in diabetic cardiomyopathy. World J Diabetes 2021; 12(6): 685-705].

Response 5: We thank the reviewer for this important comment. A correlation analysis with the most relevant patient characteristics, including diabetes mellitus type II, was included in the results of the revised manuscript to depict the most important demographic parameters that have an influence on sST-2 levels. In our study, diabetes mellitus did not show a significant correlation with sST-2 levels. (Page 5, line 176)

Comment 6: Figures. Specify the test which was conducted in the footnote. Apply to all figures. Remove speculations such as “indicating potentially lower sST2-2 levels at baseline may predict successful short-term outcomes at one month after intervention.” from the results section to the discussion.

Line 89 – please define HT

Response 6: We are grateful for this valuable addition. In all figures, statistical tests used were added in the footnote. Speculations were removed from the results. (page 6, line 201) HT was defined in the revised manuscript.

Author Response File: Author Response.pdf

Reviewer 4 Report

The aim of this work is to evaluate the sST2 levels and their possible prognostic impact regarding the success of renal sympathetic denervation (RSD) among patients who underwent this procedure as a treatment for therapy-resistant arterial hypertension. The article tried to provide data on a subject on which data are lacking, however starting with a small cohort of patients. Moreover, in a cohort of only 54 patients, sST2 levels after 3 months were measured in only 20 patients, which is insufficient for a study, especially in a study conducted without a control group.

Furthermore, I noticed several issues that need to be addressed. 

Major issues:

1. The title of the manuscript should be changed because it does not match the text. In the text the authors do not talk about the adverse outcomes at all, but about the additional information provided by sST2 levels regarding the success of RSD.
2. The introduction is way too long. Some paragraphs (80%) should be shortened and moved to the discussion manuscript section. In addition, it is interesting that in such a broad introduction there is not a single sentence that explains what RSD is and what its purpose is, all the way to line 92 in which the authors mention its advantages for the first time.
3. In the "Materials" section, the paragraph related to biomarker measurement does not explain the exact sST2 measurement time. Could authors further define "baseline measurement" since it does influence the concentration of the biomarkers (taking into account the inflammation related to the procedure for example)? In addition, the authors represented the values of sST2 using mean ± standard deviation. Biomarkers as sST2 have not-Gaussian distribution. Parametric tests on non-Gaussian data could be misleading and consequently should be avoided, especially when the small sample is so limited.
   
4. The limitations chapter is poor. To be more precise, a section relating to cohort restriction should be added here since 20 patients are not sufficient for the study as mentioned above.   
   
   Minor issues:
   
   1. There are several mistakes regarding abbreviations. Some of them are not introduced at all in the manuscript, although often used, or they are introduced incorrectly:
   
   a) in the introduction (line 39), the abbreviation RH, which should mean “resistant hypertension” is introduced in parentheses after “therapy refractory.” I can see that in the abstract, the same abbreviation was introduced correctly.
   
   b) Line 89, the abbreviation HT is not introduced at all and it is mentioned only 2 times. I would suggest removing it since it is misleading, giving the impression that you are talking out something else rather than hypertension.
   
   c) When mentioning for the first time, please state the full name of the abbreviations you use in the manuscript for sST2, LV, LVM, LVH, RR, SBP, HT, BMI, TTE, ICAM-1, VCAM-1 etc.
   
   d)Throughout the text, the authors sometimes use certain abbreviations and sometimes not. For example, from one paragraph to another the “left ventricular” is written like this or just LV, or biomarker sST2 and sST-2. Please, read the text thoroughly and correct all mistakes.
    
   
   2. In addition to confusing abbreviations, which made it difficult to understand the whole text, I have other minor comments regarding the chapters of the text.
   
   a) From lines 230 to 232, the text should be rewritten since it is not understandable (ref. 29). The symbol “±“ is missing between numbers, which gives a confusing note. Also, in line 274.
   
   The text should be written in a reader-friendly way, without pushing a reader to open so many cited articles to get the idea of your manuscript.
   
   b) In line 241 there is a truncated sentence with a ref.31.
   
   c)Line 269 has offensive language and should be rewritten. Also, the reference is not correct, please add the correct one: Ojji, D., Opie, L., Lecour, S. et al. The effect of left ventricular remodelling on soluble ST2 in a cohort of hypertensive subjects. J Hum Hypertens 28, 432–437 (2014). https://doi.org/10.1038/jhh.2013.130
   
   d)Line 270 is missing the name of the biomarker: “The serum levels in patients with hypertensive…”. “sST2” is missing, please add it.

Author Response

Dear Editor!

Dear Reviewer #4:

 

We are very grateful for the in-depth review of our manuscript and your favorable assessment of our work. Please find attached our revised version of the manuscript. We have substantially improved all major sections of the manuscript according to the reviewers’ esteemed suggestions and points of criticism. Please find below a point-by-point response invorporating all concerns and suggestions by all reviewers.

 

We do sincerely hope that in its present form you will find the manuscript acceptable for publication.

 

Sincerely yours,

 

Albert Topf

 

Reviewer 4

Comment 1: The aim of this work is to evaluate the sST2 levels and their possible prognostic impact regarding the success of renal sympathetic denervation (RSD) among patients who underwent this procedure as a treatment for therapy-resistant arterial hypertension. The article tried to provide data on a subject on which data are lacking, however starting with a small cohort of patients. Moreover, in a cohort of only 54 patients, sST2 levels after 3 months were measured in only 20 patients, which is insufficient for a study, especially in a study conducted without a control group.

Furthermore, I noticed several issues that need to be addressed.

 

Response 1: We thank the reviewer for his/her comment. We acknowledge that sample size is an issue that needs to be addressed as a limitation when interpreting the results.

 

Comment 2: The title of the manuscript should be changed because it does not match the text. In the text the authors do not talk about the adverse outcomes at all, but about the additional information provided by sST2 levels regarding the success of RSD.

 

Response 2: We thank the reviewer for the important input. The title of the manuscript was changed to “sST2 predicts short term therapy success in patients with therapy resistant hypertension after renal sympathetic denervation”.

 

Comment 3: The introduction is way too long. Some paragraphs (80%) should be shortened and moved to the discussion manuscript section. In addition, it is interesting that in such a broad introduction there is not a single sentence that explains what RSD is and what its purpose is, all the way to line 92 in which the authors mention its advantages for the first time.

 

Response 3: We thank the reviewer for this important comment. The introduction was shortened and rewritten to better address the problem.

 

Comment 4: In the "Materials" section, the paragraph related to biomarker measurement does not explain the exact sST2 measurement time. Could authors further define "baseline measurement" since it does influence the concentration of the biomarkers (taking into account the inflammation related to the procedure for example)? In addition, the authors represented the values of sST2 using mean ± standard deviation. Biomarkers as sST2 have not-Gaussian distribution. Parametric tests on non-Gaussian data could be misleading and consequently should be avoided, especially when the small sample is so limited.

 

Response 4: We are grateful for this important comment. Baseline measurements are defined as laboratory markers or patient characteristics, measured before renal denervation or performed with laboratory samples taken before renal denervation at hospital admission. Therefore, the procedure does not have an influence on baseline laboratory parameters. (page 2, line 94) The Kolmogorov-Smirnov test revealed a normal distribution among all parameters tested, including sST-2 (p=0.2), and therefore, characteristics were shown as mean ± standard deviation.

 

Comment 5: The limitations chapter is poor. To be more precise, a section relating to cohort restriction should be added here since 20 patients are not sufficient for the study as mentioned above.  

 

Response 5: We thank the reviewer for this important comment. The limitations chapter was revised to better address to the main limitations of our study including a small study cohort and a pre-selected study group.

 

Comment 6:

1. There are several mistakes regarding abbreviations. Some of them are not introduced at all in the manuscript, although often used, or they are introduced incorrectly:
2. a) in the introduction (line 39), the abbreviation RH, which should mean “resistant hypertension” is introduced in parentheses after “therapy refractory.” I can see that in the abstract, the same abbreviation was introduced correctly.
3. b) Line 89, the abbreviation HT is not introduced at all and it is mentioned only 2 times. I would suggest removing it since it is misleading, giving the impression that you are talking out something else rather than hypertension.
4. c) When mentioning for the first time, please state the full name of the abbreviations you use in the manuscript for sST2, LV, LVM, LVH, RR, SBP, HT, BMI, TTE, ICAM-1, VCAM-1 etc.

d)Throughout the text, the authors sometimes use certain abbreviations and sometimes not. For example, from one paragraph to another the “left ventricular” is written like this or just LV, or biomarker sST2 and sST-2. Please, read the text thoroughly and correct all mistakes.

 

Response 6: Thank you very much for this important advice considering abbreviations. The manuscript was checked and all mistakes were corrected accordingly.

 

Comment 7:

2. In addition to confusing abbreviations, which made it difficult to understand the whole text, I have other minor comments regarding the chapters of the text.
3. a) From lines 230 to 232, the text should be rewritten since it is not understandable (ref. 29). The symbol “±“ is missing between numbers, which gives a confusing note. Also, in line 274.

The text should be written in a reader-friendly way, without pushing a reader to open so many cited articles to get the idea of your manuscript.

31. b) In line 241 there is a truncated sentence with a ref.31.

c)Line 269 has offensive language and should be rewritten. Also, the reference is not correct, please add the correct one: Ojji, D., Opie, L., Lecour, S. et al. The effect of left ventricular remodelling on soluble ST2 in a cohort of hypertensive subjects. J Hum Hypertens 28, 432–437 (2014). https://doi.org/10.1038/jhh.2013.130

d)Line 270 is missing the name of the biomarker: “The serum levels in patients with hypertensive…”. “sST2” is missing, please add it.

 

Response 7: We thank the reviewer for the productive evaluation of our manuscript. Corrections were made in the revised manuscript.

 

 

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Dear Authors, thank you for addressing comments. The paper was significantly improved and I have no further comments. 

Author Response

Reviewer #2:

 

We are very grateful for your final verdict on our manuscript.

Reviewer 3 Report

No further comments.

Author Response

Reviewer #3:

 

We are very grateful for your final verdict on our manuscript.

Reviewer 4 Report

The authors improved their manuscript, especially the Introduction part, and answered all the major concerns raised in the first revision. However, there are many issues that need to be addressed. Many sentences are misleading and confusing, such as the text between lines 134-136, 185-187. From the context we can understand what the authors wanted to point out; however, they did not do it properly. All text should be read in detail to improve readability, not only those two examples mentioned above.

A part of many grammatical errors in the paper, the authors did not correct all the mistakes raised in the previous revision. In the comments section, I see that they agreed to correct them, however, in the manuscript I can still notice a truncated sentence, unintroduced abbreviations (such as RR in the picture, LVH and TTE) and incorrect references. Also, some abbreviations are introduced at the beginning of the text, but from chapter to chapter or in the same chapter, the authors use both the abbreviation and the full name at the same time (BP and SBP for example). Also, the second paragraph on page 2 lacks a reference. 

Author Response

Dear Editor!

Dear Reviewers #4:

 

We are very grateful for the second in-depth review of our manuscript and your favorable assessment of our work. Please find attached the improved version of our manuscript.

 

We do sincerely hope that in its present form you will find the manuscript acceptable for publication.

 

Sincerely yours,

 

Albert Topf

 

 

Reviewer #4:

 

We acknowledge that there has been a number of weaknesses in the manuscript that require clarification.

 

1. We have checked all abbreviations throughout the text and introduced every abbreviation at the appropriate place. “blood pressure” has been replaced with “BP” in multiple paragraphs. “Left ventricular hypertrophy” has been replaced with “LVH” wherever appropriate.

 

2. For better consistency, the abbreviation “sST2” in figures 2, 3 and 4 has been replaced with “sST-2” as in the text.

 

3. For better consistency, the abbreviations “RRsystol” and “RRdiastol” in figure 1 have been replaced with “SBP” and “DBP” as in the text.

 

4. Thank you for indicating ll. 134-136 to be confusing. We have clarified that sentence in the statistics section.

 

5. Thank you for pointing out the sentence ll. 185-187 at the end of the results section.” We have rephrased this sentence to improve comprehension.

Round 3

Reviewer 4 Report

The authors have clarified most of the issues raised in previous revisions, not all of them. However, that is the decision of the author. Numerous errors in the text have also been corrected. This manuscript is now well written and the general impression of the manuscript has greatly improved.