Type 1A Endoleak after TEVAR in the Aortic Arch: A Review of the Literature

Round 1

Reviewer 1 Report

TITLE AND ABSTRACT ok

INTRODUCTION
#1 In this paper we aim to describe how the incidence of endoleak (in particular type 1 endoleak) variates among different techniques and which role it could have in postoperative management of such patients. 
You should keep the statement in line with title and whole paper, so not "in particular" type 1. Moreover, Authors should briefly explain in the introduction why they decided to focus only on type 1 endoleaks.

MATERIALS AND METHODS
#2..was focused on the period between January 2012 and March 2022. Only studies from 2012 to 2022 were selected, to keep our selection as contemporary as possible. 
Sentences redundant.

#3..Articles selection was independently per-70 formed by three authors (L.S., F.P. and N.P.) 
Did they focus each on one of the specific databases or they used all of them and then compared the results?

#4 - Figure 1: what the * in the first left upper box stands for?

RESULTS
#5 - Lines 94-105: please rephrase in order to make this paragraphs more homogeneous and fluent 

#6 - Figures 2 and 3: beside showing the technique, images should provide evidence of type 1 endoleak, otherwise do not seem to add specific information

#7 - Table 1: confusing and need to be more organised, i.e. according to groups/type of technique (first group 1, listing all papers included, number of type 1 endoleak and a final line with total of papers and total of type 1 per group); percentages would also help

#8 - Paragraphs 3.1-3.2-3.3-3.4: confusing and need to be more organised; I would describe first reported ranges of incidence among studies, eventual specific charateristics, then I would describe specific reports from studies

DISCUSSION
#9 - Among most frequent complications we surely find type 160 1 endoleaks
Please, report percentages of incidence

#10 - throughout the discussion session I would report more numbers when talking about rates, incidence, etc...

Author Response

Reviewer 1

Thank you for your thorough revision. We found many helpful observations which guided us in revising our paper. We made a major revision following your observations (whose answers are hereby listed) and uploaded it, we look forward to any additional opinion.

INTRODUCTION
#1 In this paper we aim to describe how the incidence of endoleak (in particular type 1 endoleak) variates among different techniques and which role it could have in postoperative management of such patients. 
You should keep the statement in line with title and whole paper, so not "in particular" type 1. Moreover, Authors should briefly explain in the introduction why they decided to focus only on type 1 endoleaks.

We corrected and expanded our sentence, explaining why we only focused on type 1 endoleaks.

MATERIALS AND METHODS
#2..was focused on the period between January 2012 and March 2022. Only studies from 2012 to 2022 were selected, to keep our selection as contemporary as possible. 
Sentences redundant.

We rewrote our sentence, hopefully making it more fluent.

#3..Articles selection was independently per-70 formed by three authors (L.S., F.P. and N.P.) 
Did they focus each on one of the specific databases or they used all of them and then compared the results?

They all used all of them and then compared results, to limit bias and errors.

#4 - Figure 1: what the * in the first left upper box stands for?

It was a typo and has been corrected.

RESULTS
#5 - Lines 94-105: please rephrase in order to make this paragraphs more homogeneous and fluent 

In our new draft, we rephrased most of our results and discussion in order to make them more fluent. We hope to have your point of view on our latest draft.

#6 - Figures 2 and 3: beside showing the technique, images should provide evidence of type 1 endoleak, otherwise do not seem to add specific information

We were hoping to add these images to add details about different techniques but we are willing to take them out if they appear to be out of topic.

#7 - Table 1: confusing and need to be more organised, i.e. according to groups/type of technique (first group 1, listing all papers included, number of type 1 endoleak and a final line with total of papers and total of type 1 per group); percentages would also help

We rearranged the table and added percentages

#8 - Paragraphs 3.1-3.2-3.3-3.4: confusing and need to be more organised; I would describe first reported ranges of incidence among studies, eventual specific charateristics, then I would describe specific reports from studies

We rearranged our paragraphs as suggested

DISCUSSION
#9 - Among most frequent complications we surely find type 160 1 endoleaks
Please, report percentages of incidence

The paragraph was rephrased and the sentence was cut out

#10 - throughout the discussion session I would report more numbers when talking about rates, incidence, etc...

We added more incidence percentages and numbers as suggested. We also rephrased most of our discussion to make it more fluent.

Reviewer 2 Report

The review titled ” Type 1 endoleak after TEVAR in the aortic arch: a review of the literature” by L. Scurto and co-workers, describes how the incidence of type 1 endoleak variates among different techniques of endovasculat treatment of aortic arch disease (chimney procedures, TEVAR with fenestrated and branched devices) and which role it could have in postoperative management of such patients. Out of 1277 records, a total of 48 studies were selected, including 3114 patients.

Type 1 endoleak occurred in 248 of them (7.7%) with a mean incidence of 18.8% in chimney procedures, 4.8% and 3% respectively in fenestrated and branched devices and 2.2% in in situ fenestration.

The authors conclude that total endovascular replacement for treatment of aortic arch disease still is the most suitable option especially in frail patients and emergency settings, providing acceptable outcomes in patients to fragile to undergo open surgery. However, type 1 Endoleak is a concern with all types of endovascular aortic repair as it can compromise the outcomes of the procedure. In particular, type I endoleak rates clearly appear to be significantly higher in chimney procedures.

This reported review is interesting and the study is well done.

However some points are opened to criticism and should be addressed and/or corrected.

Some of these points ae reported in the limitations of the study.

I believe that it is not very correct to compare these different endovascular  techniques for treatment of aortic arch, which are usually chosen on the basis of the patient's anatomy and pathology. Furthermore, the operator's experience greatly can affect the results.

Two points must certainly be corrected in the results and in the discussion. The first one is the influence of the aortic arch pathology (aneurysm, dissection, PAU or IHM) and the second the influence of the proximal landing zone on the choice of treatment technique and following results.

Author Response

Thank you for your review. We are glad you found our topic of interest to be interesting. We found your observatons very useful and kept them in mind when writing our latest draft (which we uploaded).

As you noted, there is an obvious lack of uniformity when comparing such studies. We however chose to focus on such topic despite this limitation due to the interesting starting points it could offer when it comes to post operative management of such procedures. In our study we try to underline how, especially in procedures link with a high risk of type 1 endoleak, a thorough follow up and post operative management could be key in improving prognosis, reintervention rate, and even survival. We do not aim to determine whether or not one technique is superior to the other, due to how hard it is to make a bias-free comparison.

This is why in our submitted we did not compare outcomes in procedures performed for different arch pathologies. Nonetheless, we found your point of view very compelling and went back to take a second look at our selected papers. The significance we found in type 1 endoleak rates when we sorted our cohort by technique could not be found when we sorted them by pathology. We did not analyze how different complications may have different incidence rate though, since it was not our main goal. A bit more complex appears to be the influence of the proximal landing zone. Though it appears not to be linked itself to the type 1 endoleak incidence (as we stated in our paper) it is true that it can influence the choice of technique and create a bias that is difficult to overcome. Stil, having chosen to focus more on how this kind of complication affects post operative management in such patients than how to lower its rate, we decided to go through with our analysis. We added some considerations in our limitation paragraph.