PONE-D-19-20560

Clinical outcomes and mortality in old and very old patients undergoing cardiac resynchronization therapy

PLOS ONE

Dear Dr. Luiz Eduardo Montenegro Camanho

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

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ACADEMIC EDITOR: 

Manuscript underwent two different reviewers who suggested minor (only reference's list improvement) and major revsion (regarding data that must be explained better). See my additional comment for authors below. 

Authors must be follow reviewers suggestions before manuscript acceptance.

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Giuseppe Coppola

Academic Editor

PLOS ONE

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Additional Editor Comments:

Kind authors, thank you for submitting your manuscprit To Plos One journal. The manuscript is well written and interesting. The topic focus about elderly population undergoing CRT that is not well representad in the biggest clinical trials. You have underline how the response to CRT and the cardiovascular mortality were not affected by advanced age. Thus, advanced age should not be an exclusion factor for this therapy. I agree with you considering age as not an exclusion criteria to CRT in comparison to, for example, life expectancy and/or comorbidity burden; so, probably, discussion must be improved considering this well known findings and something about the importance role of QRS Shortening after CRT as possible variable to predict CRT response. For example you can consider our previous work "Magnitude of QRS duration reduction after biventricular pacing identifies responders to cardiac resynchronization therapy" to have a look about this topic.

I have appreciate very much when you underlined the lack of the universal definition of CRT responders and how the use of ultrasound-guided axillary or cephalic vein access has been increasingly established as a safe and effective technique related to lower rates of acute complications.

Your manuscript underwent two different reviewers who suggested minor (only reference's list improvement) and major revsion (regarding data that must be explained better).

I hope you can follow reviewers' suggestions to permit the acceptance of your interesting manuscript.

My best regards.

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

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3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: No

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

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Reviewer #1: Yes

Reviewer #2: Yes

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Cardiac resynchronization therapy (CRT) is a successful strategy for heart failure (HF) patients. In the epidemiological context of recent decades, the average age of the population tends to increase, especially elderly and very elderly patients. Moreover, in the near future, it is expected a increased worldwide prevalence of heart failure. In light of this scenary, there is an urgent need for study CRT in the setting of very elderly patietns.

In the study of Luiz Eduardo Montenegro Camanho et al. it has been very interesting to have analyzed the impact of advanced age on the clinical response and cardiovascular and total mortality of patients undergoing CRT. In this regard, it would be interesting to point out that other studies have also previously evaluated clinical outcomes in elderly patients subjected to CRT (see: “Clinical outcomes in cardiac resynchronization therapy-defibrillator recipients 80 years of age and older ”, Doi: 10.1093/europace/euv222) and evaluation of importance of CRT (see: “Non-responders to cardiac resynchronization therapy: Insights from multimodality imaging and electrocardiography. A brief review”, Doi: 10.1016/j.ijcard.2016.09.037).

Returning to the manuscript, I would like congratulate all the authors contributing to this good article and research work. The study population is big enough, this is an important advantage, as it gives more statistical power. However, the population will have to be implemented to find application in the guidelines. Finally, the results were very significant and further encouraged the use of CRT in elderly patients. Conclusions of study are presented in an appropriate fashion and are supported by interesting data. The article is presented in an intelligible fashion.

In conclusion, given the overall work, I accept manuscript with minor revision concerning a small implementation of bibliography, reporting the aforementioned works and other.

Reviewer #2: There are 3 important data to explain:

- The difference in ischemic and non ischemic population in the third Group

- the difference in mortality between Crtp and Crtd

- the difference in response between population with LBBB and other wide Qrs

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Reviewer #1: No

Reviewer #2: No

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Clinical outcomes and mortality in old and very old patients undergoing cardiac resynchronization therapy

PONE-D-19-20560R1

Dear Dr. Luiz Eduardo Montenegro Camanho

We are pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it complies with all outstanding technical requirements.

Within one week, you will receive an e-mail containing information on the amendments required prior to publication. When all required modifications have been addressed, you will receive a formal acceptance letter and your manuscript will proceed to our production department and be scheduled for publication.

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With kind regards,

Giuseppe Coppola

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Kind Author, after careful new evaluation I can say that your manuscript underwent full revision point by point according with reviewer's suggestions.