Journal Club

This is a legacy content and is all our forum is now taking place on Discord.

Please or Register to create posts and topics.

Journal Club 09/07/2020

Hello everyone! We are returning for Journal Club with tutor Dr Kirolos Michael.

The article for the week will be released at 18:00, giving you 30 minutes to analyse the paper. In future sessions it will be released at 18:15 to replicate the time given in AFP interviews.

Hello all the link to the chat is attached below. we will start shortly!

https://www.chatbro.com/en/235sP/

 

Danish HaFeez
Danish HaFeez

6:30 pm
Hello
Beth Clayton

6:30 pm
Hello! Can people please post their Name, email, University and year of study as an intro please!
Beth Clayton

6:30 pm
We will give everyone 5 minutes to log in
Leah AB

6:31 pm
Leah Argus, leah.argus@student.manchester.ac.uk, Uni of Manchester, Intercalating after Y4
Danish HaFeez
Danish HaFeez

6:31 pm
Danish Hafeez, danish.hafeez@student.manchester.ac.ul, Manchester and going into final year ?
Daniel Ahari
Daniel Ahari

6:31 pm
Daniel Ahari, daniel.ahari@student.manchester.ac.uk; Uni of Manchester, just finished Y4, going into intercalation
Annabel Chadwick, annabel.chadwick@student.manchester.ac.uk, UoM and also going into final year
Kirolos Michael
Kirolos Michael

6:31 pm
Hello everyone, Kirolos here. I’ll be your tutor for journal club for anyone who’s new
Danielle hartland danielle.hartland@student.manchester.ac.uk uni of Manchester and going into final year
Charlie McVickers, charles.mcvickers@student.manchester.ac.uk, Uni of Manchester, going into final year
Becca Vitarana, rebecca.vitarana@student.manchester.ac.uk, uni of manchester and going into fourth year 🙂
Lily Helston
Lily Helston

6:31 pm
Lily Helston, olivia.helston@student.manchester.ac.uk, UoM, going into 4th year post intercalation
Shamia C
Shamia C

6:31 pm
Shamia Chowdhury, shamia.chowdhury@student.manchester.ac.uk, UoM, going to intercalate between year 4 and 5
Rox M
Rox M

6:32 pm
Roxana Moscalu, roxana.moscalu@student.manchester.ac.uk, Uni of Manchester, going into final year
Xenia Sara

6:32 pm
Xenia Sara, Xenia.sara@student.manchester.ac.uk, UoM, 4th > intercalation
Karan
Karan

6:32 pm
Karan Daga karan.daga@student.manchester.ac.uk, UoM, going into 4th year
Ashka Moothoosamy, ashka.moothoosamy@student.manchester.ac.uk, uni of Manchester, going into Year 4
Alexandra Brooks
Alexandra Brooks

6:32 pm
Hello everyone. Alex Brooks, alexandra.brooks@student.manchester.ac.uk, Uni of Manchester, going into 5th year
Beth Clayton

6:33 pm
I’m Beth and I’m Journal Club lead for Scalpel, going into 5th year from UoM. Kirolos is our tutor for the sessions this year and he will be leading all future sessions
Kirolos Michael
Kirolos Michael

6:33 pm
Right, if everyone has introduced themselves, shall we get started?
Callum Docherty
Callum Docherty

6:34 pm
Callum Docherty callum.docherty@student.manchester.ac.uk, Manchester, going into final year
Ali Tariq

6:34 pm
Hi! Ali Tariq, ali.tariq-4@postgrad.manchester.ac.uk, UoM, going into final year
Patricia Vinchenzo, pvinchenzo01@qub.ac.uk, final year 🙂
celina akhtar
celina akhtar

6:34 pm
Celina Akhtar, celina.akhtar@student.manchester.ac.uk, uni of manchester, going into year 4
Beth Clayton

6:34 pm
Just a quick reminder about the pre-club questionaire, I trust everyone has filled it in but here you go just in case https://docs.google.com/forms/d/e/1FAIpQLSfAdeVnlDzI
Jared McSweeney
Jared McSweeney

6:34 pm
jared.mcsweeney@student.manchester.ac.uk Manchester, 4th year going into intercalation
Daniel Warrington
Daniel Warrington

6:35 pm
Hi everyone, first journal club for me. Daniel Warrington. daniel.warrington@student.manchester.ac.uk, UoM, 4th > intercalation
Francine Anderson
Francine Anderson

6:35 pm
Fran Anderson, francine.anderson@postgrad.manchester.ac.uk (Final year – Physician Associate)
Beth Clayton

6:35 pm
Its 18:35, shall we start?
Steffi
Steffi

6:36 pm
Staff McLucas, steffi.mclucas@postgrad.manchester.ac.uk (Final Year – PA)
Kirolos Michael
Kirolos Michael

6:36 pm
Welcome everybody
Kirolos Michael
Kirolos Michael

6:36 pm
Has everyone had a chance to read the paper?
Daniel Ahari
Daniel Ahari

6:36 pm
Yep just about!
Yep
Kirolos Michael
Kirolos Michael

6:36 pm
Can somebody describe what the aim for this study is?
Rox M
Rox M

6:37 pm
compare mnimally invasive techniques for aortic valve replacement to conventional sternotomy…broadly speaking
Karan
Karan

6:37 pm
The aim was to compare 3 minimally invasive approaches to aortic valve replacement, specifically with regard to operative and recovery times as well as complications
To compare the mini-thoracotomy technique to mini sternotomy and classic sternotomy in the context of aortic valve replacement in terms of outcomes
Danish HaFeez
Danish HaFeez

6:38 pm
to compare invasive techniques for aortic valve replacement
Kirolos Michael
Kirolos Michael

6:38 pm
Fantasic
Karan
Karan

6:38 pm
2* minimally invasive with conventional sternotomy
Daniel Ahari
Daniel Ahari

6:38 pm
comparing the post-op complications of minimally invasive techniques for sternotomy with conventional sternotomies in a single North American centre across 4 years and 500 patients.
Daniel Ahari
Daniel Ahari

6:39 pm
(For AVR, lol)
Kirolos Michael
Kirolos Michael

6:39 pm
Okay so there were 3 techniques for aortic valve replacement (AVR), mini-thoracotomy, mini-sternotomy & conventional sternotomy, compared in terms of demgraphics, operative morbidity, mortality & post-op complications
Kirolos Michael
Kirolos Michael

6:40 pm
What was the study design? Daniel touched on it
retrospective?
Shamia C
Shamia C

6:40 pm
So this was a retrospective cohort study?
Retrospective study?
Shamia C
Shamia C

6:40 pm
So this was a retrospective cohort study?
Shamia C
Shamia C

6:40 pm
So this was a retrospective cohort study?
Jared McSweeney
Jared McSweeney

6:40 pm
Retrospective study
Jared McSweeney
Jared McSweeney

6:40 pm
Retrospective study
Daniel Warrington
Daniel Warrington

6:40 pm
Retrospective cohort study
Shamia C
Shamia C

6:40 pm
sorry didn’t realise it sent a few times
Daniel Ahari
Daniel Ahari

6:40 pm
I agree with Shamia I think^
Danish HaFeez
Danish HaFeez

6:40 pm
retrospective observational analytical study?
retrospective review?
Rétrospective study
Alexandra Brooks
Alexandra Brooks

6:40 pm
retrospective cohort study, I thought too
Kirolos Michael
Kirolos Michael

6:40 pm
Great. So its retrospective
Alexandra Brooks
Alexandra Brooks

6:41 pm
retrospective cohort study, I thought too
Callum Docherty
Callum Docherty

6:41 pm
Yeah retrospective cohort
Callum Docherty
Callum Docherty

6:41 pm
Yeah retrospective cohort
Callum Docherty
Callum Docherty

6:41 pm
I think
Kirolos Michael
Kirolos Michael

6:41 pm
those that said cohort, anybody want to explain why they think its cohort?
Daniel Ahari
Daniel Ahari

6:42 pm
Because two (or more in this case) groups are being compared. The groups are cohorts. Ostensibly the only difference between the groups is what approach is being used (the intervention)
Daniel Ahari
Daniel Ahari

6:42 pm
Could argue it’s two groups though: one group of minimally invasive, one group of conventional, but they’re definitely not equal sized.
i thought cohort meant longitudinal…so i didn’t know whether to say it!
Kirolos Michael
Kirolos Michael

6:43 pm
Great Daniel. Everyone clear on that? Anybody know why for example this isn’t a case-control?
Danish HaFeez
Danish HaFeez

6:43 pm
Isn’t a retrospective cohort based more on separating by risk factor?
Danish HaFeez
Danish HaFeez

6:44 pm
Because participants weren’t matched with controls it’s not a case-control
Kirolos Michael
Kirolos Michael

6:44 pm
So yes, in this case, you have 3 groups of patients. Each group has had a different exposure (i.e. the different intervention) & they are followed up to compare the differences in outcome
Lily Helston
Lily Helston

6:45 pm
In a case-control analyses, would the aim not also to identify potential contributing risk factors?
Lily Helston
Lily Helston

6:45 pm
*would the aim be
Kirolos Michael
Kirolos Michael

6:45 pm
That’s right Lily
Danish HaFeez
Danish HaFeez

6:45 pm
Great- makes sense!
Kirolos Michael
Kirolos Michael

6:46 pm
with a case-control, you start with 2 or more groups that have different outcomes of interest, then you look back retrospectively to see the different exposures in each group to work out if there is a difference in exposure to certain risk factors (or interventions) that could explain the different outcomes you started with
Kirolos Michael
Kirolos Michael

6:48 pm
Everyone clear on that? Any more questions. If not, shall can someone quickly describe the population of this study?
Yes that makes sense, thank you
Francine Anderson
Francine Anderson

6:48 pm
Yes thank you
Daniel Ahari
Daniel Ahari

6:48 pm
Not to derail too much but for the case control then, with that sort of blueprint you’ve outlined could that be as simple as two wards where one has a higher infection rate for example – and then basically you’re just trying to figure out why?
Thanks
Thanks
Beth Clayton

6:48 pm
The population was 503 patients who specifically underwent just aortic valve replacements over a 3 year period at a single centre
>18 years of age
Rox M
Rox M

6:48 pm
503 patients, over 18 year old
Rox M
Rox M

6:49 pm
503 patients, over 18 year old
Leah AB

6:49 pm
Pregnant women were also excluded
as well as having isolated AVRs
Jared McSweeney
Jared McSweeney

6:49 pm
503 patients undergoing only AVR. Patients were over 18 yrs. Pregnant women were excluded.
Rox M
Rox M

6:49 pm
and patients with simultaneous operations also excluded, as well as pregnant women
sorry can I ask, was it cohort or not cohort? as we werent looking at risk factors
Kirolos Michael
Kirolos Michael

6:50 pm
Exactly Daniel. An even simpler example of a case-control would be looking at 2 groups of patients, 1 group with lung cancer, the other without. Looking at a risk factor (smoking), and comparing the rates of smoking in each group retrospectively, with othervariables being matched (i.e. equal distribution in each group), if more smokers were in the lung cancer group, you could argue smoking is a risk factor and implies a causal relationship etc.
Kirolos Michael
Kirolos Michael

6:51 pm
Great everyone with the population
Daniel Ahari
Daniel Ahari

6:51 pm
Cheers thank you
Kirolos Michael
Kirolos Michael

6:51 pm
Yes Trisha, it s a cohort. It’s not necessarily risk factors that you are looking at, rather “exposure”. Exposure can be anything from a “risk factor” or an “intervention” as that would classify as an exposure
Thank you!
Kirolos Michael
Kirolos Michael

6:52 pm
If you think of these studies in terms of exposures rather than risk factors, it makes it easier to apply when the exposure or “risk factors” was actually an intervention or a drug etc.
Kirolos Michael
Kirolos Michael

6:52 pm
Right, shall we move to the results
Kirolos Michael
Kirolos Michael

6:53 pm
Firstly, with table 1 on the demographics
Kirolos Michael
Kirolos Michael

6:53 pm
Does anyone have any comments about the demographics between the different groups? Anything that caught anyone’s eye?
Leah AB

6:53 pm
The STS score is significantly lower in the MT group which could account for better outcomes
The STS scores were significantly different
Karan
Karan

6:54 pm
The cohort size for MT group is nearly double that of the other interventions
Kirolos Michael
Kirolos Michael

6:54 pm
Great observations from all of you
Kirolos Michael
Kirolos Michael

6:55 pm
As Karan said, there are a lot more in the mini-thoracotomy (MT) group than any other group in this centre
Daniel Ahari
Daniel Ahari

6:55 pm
The patients are of an older age group (as is expected to be honest) which means that maybe the results aren’t generalisable to younger patients.
Leah AB

6:55 pm
The cohort size may be justified by MT being their first choice approach, again this could account for better outcomes
Kirolos Michael
Kirolos Michael

6:55 pm
Also, the STS score is significantly lower in the MT group
could be other confounding factors not mentioned
Kirolos Michael
Kirolos Michael

6:56 pm
Has anyone figured what the STS score might be without googling it?
Danish HaFeez
Danish HaFeez

6:56 pm
smoking status was lower in the MT group- which was statistically significant, but very small samples
Kirolos Michael
Kirolos Michael

6:56 pm
We will discuss about STS score later if it actually accounted for the better outcomes or not
Daniel Ahari
Daniel Ahari

6:56 pm
I’m guessing it’s a measurement of the health of the patient/suitability for surgery
Score for assessing suitability for surgery ?
Daniel Ahari
Daniel Ahari

6:57 pm
E.g like ASA grading
Leah AB

6:57 pm
North America’s score for cardiac surgery risk prediction, the European equivalent is EUROScore
Alexandra Brooks
Alexandra Brooks

6:57 pm
yeah I thought it was risk for the surgery
Kirolos Michael
Kirolos Michael

6:58 pm
Absolutely right. So without access to google or anything, you can work out its a score that predicts morbiditiy & mortality following cardiothoracic surgery. Similar to P-POSSUM etc where you input various pre-operative details for a patient and it comes up with a score that predicts morbidity & mortality
Kirolos Michael
Kirolos Michael

6:59 pm
A high score = increased postoperative morbidity & mortality
Kirolos Michael
Kirolos Michael

6:59 pm
So the patients in the MT group had a lower STS score & therefore reduced post-operative mortality & morbidity
Kirolos Michael
Kirolos Michael

7:01 pm
Also, Danish, good for pointing out smoking status is different. 5.2% in the MT group & 10.3% in the CS group. P= 0.02
Kirolos Michael
Kirolos Michael

7:01 pm
is this statistically significant?
Beth Clayton

7:01 pm
It is yeah
Danish HaFeez
Danish HaFeez

7:01 pm
yes
Leah AB

7:02 pm
Yes, significant p was set at <0.05
Daniel Ahari
Daniel Ahari

7:02 pm
Yeah by their own metrics
Alexandra Brooks
Alexandra Brooks

7:02 pm
usually less than 0.05 is yes
Kirolos Michael
Kirolos Michael

7:02 pm
Great. So it’s statistically significant to the 0.05 level
Danish HaFeez
Danish HaFeez

7:02 pm
at the 95% confidence level
Kirolos Michael
Kirolos Michael

7:02 pm
Can somebody describe the rest of the results before we move onto strengths & weaknesses?
Danish HaFeez
Danish HaFeez

7:04 pm
but as it is statistically significant- but the actual numbers are relatively small- how would you advice interpreting it? Limited power?
Danish HaFeez
Danish HaFeez

7:05 pm
MT was associated with shorter bypass times, shorter times on ventilator and shorter hospitalisation stay- all significantly less than other 2 interventions
Danish HaFeez
Danish HaFeez

7:05 pm
MT also “trended” toward better survival
Daniel Ahari
Daniel Ahari

7:05 pm
And to follow up on Danish’s summary; post-operative complications however did not vary significantly between the cohorts
yes trended as it wasnt significant
Kirolos Michael
Kirolos Michael

7:06 pm
It is statistically significant with the numbers involved in the study. That’s all you can really say. The study has sufficient power to identify statistical significance at the 0.05 level. By increasing the number of people in the study, with the same magnitude of effect, you would ultimately make the results more significant e.g. at the <0.01, <0.001 level… If that makes sense
Danish HaFeez
Danish HaFeez

7:07 pm
Kirolos Michael, yup- that makes sense- thank you!
By ‘with the same magnitude of effect’ do you mean that the p values will only get more significant if the difference between groups is actually there?
Kirolos Michael
Kirolos Michael

7:08 pm
Great so yes MT has shorter bypass time, ventilator time & shorter hospitalisation and the differences were significant
Kirolos Michael
Kirolos Michael

7:09 pm
Annabel Chadwick, yes that’s right. If the difference that we saw is *really* there, having let’s say 1,000 people in the study showing the same mean difference would make the results even more statistically significant, reducing your p value even more
but not better survival? as this was not significant
Kirolos Michael
Kirolos Michael

7:10 pm
Yes, so as you may have noticed, the difference in survival (30 day mortality) as well as postoperative complications were not statistically significant
thank you!
Danish HaFeez
Danish HaFeez

7:11 pm
Could argue that with an increased sample- survival may become a significant difference because of increased power?
Danish HaFeez
Danish HaFeez

7:11 pm
as the p value is affected by sample size
Kirolos Michael
Kirolos Michael

7:11 pm
So you can’t with 95% certainty conclude that the difference in 30-d mortality & complications we saw was NOT due to chance
Kirolos Michael
Kirolos Michael

7:13 pm
Danish HaFeez, Agreed. If this difference really exists, having more people in the study might push the difference into significance. It could also demonstrate that there is no difference on the converse
Kirolos Michael
Kirolos Michael

7:13 pm
What are the strengths of this study?
yes but you take this into account when running the stats so you dont fish for a significant result
Leah AB

7:14 pm
It compares minimally invasive techniques to each other and to more invasive techniques, which provides more information than some studies included in the literature review
Leah AB

7:14 pm
It compares minimally invasive techniques to each other and to more invasive techniques, which provides betteer information than some studies included in the literature review
replicable
easily replicable i mean
Danish HaFeez
Danish HaFeez

7:15 pm
Adjusted for demographic variables and preoperative conditions when assessing outcomes
Danish HaFeez
Danish HaFeez

7:16 pm
to reduce the effects of confounders
Reasonably equal distribution across groups – although difference in STS scores they are all in the ‘low risk’ group
Danish HaFeez
Danish HaFeez

7:16 pm
to reduce the effects of confounders
Daniel Ahari
Daniel Ahari

7:16 pm
They’re using externally validated and standardised measurements such as the STS grading
Kirolos Michael
Kirolos Michael

7:17 pm
Trisha Alexandra, So with any study, the more the number of subjects the better, the higher the power of your study, the more you can be confident of the results (i.e. the better the statistical significance). Remember with these studies, you are trying to identify differences that you can apply to the whole population (that’s the point of doing a statistical test, is this difference there or due to chance). Some studies do power calculations. You start by predicting the magnitude of effect/difference you expect to see & your significance & it will calculate the minimum number of patients you need to see a statistically significant effect case on how big the difference you expect is (smaller differences need more patients in the study to make them statistically significant & vice versa)
Alexandra Brooks
Alexandra Brooks

7:17 pm
Also I know we spoke about the sample size above but it does have a relatively large sample compared to other studies looking at mini thoracotomy
Thank you!
Kirolos Michael
Kirolos Michael

7:17 pm
Great comments everyone
Kirolos Michael
Kirolos Michael

7:18 pm
Alexandra Brooks, Probably not, but there is a reason why the sample size isn’t large
Kirolos Michael
Kirolos Michael

7:18 pm
Any other obvious strength of this strength (linked in to why the sample size isn’t large, relatively speaking)?
Daniel Ahari
Daniel Ahari

7:18 pm
Single centre
Daniel Ahari
Daniel Ahari

7:19 pm
So it’s the same surgeons operating
Beth Clayton

7:19 pm
Yeah single centre
Kirolos Michael
Kirolos Michael

7:19 pm
Great. Single centre, same surgeons (in fact, only 4 surgeons in this trial), you’re keeping more things standardised this way.
Kirolos Michael
Kirolos Michael

7:19 pm
A weakness would in turn be that that number of patients isn’t very big
Leah AB

7:19 pm
I thought that would be a weakness as it’s not as applicable to other centres?
Kirolos Michael
Kirolos Michael

7:19 pm
any other weaknesses?
Beth Clayton

7:19 pm
But at the same time, results could be due to the expertise/experience of the surgeon?
But that may also be a limitation as the patient population may not be representative of the population
Short follow up of 30 days
Danish HaFeez
Danish HaFeez

7:20 pm
that no control for human factors- such as comfort/experience of surgeons in each intervention which could skew results
Kirolos Michael
Kirolos Michael

7:20 pm
Leah AB, great. Its a strength and a weakness. You can’t necessarily apply this result to every centre in the USA, let alone in the whole world
Daniel Ahari
Daniel Ahari

7:20 pm
You can spin it both ways probably? If everyone is being operated on by the same surgeons, differences are less likely to be due to the skill of the surgeons
Alexandra Brooks
Alexandra Brooks

7:20 pm
me too Leah, I thought it to be a weakness. Also not all the surgeons perform all the surgeries so there may be some skew with the expertise in the surgeons on the results
Kirolos Michael
Kirolos Michael

7:21 pm
All good points
America has a very different health care system and we dont know whether people were excluded because they had no insurance or could afford the cost? not sure….reduced generalisability
Danish HaFeez
Danish HaFeez

7:21 pm
length of stay based on aggregate data (before/after procedure) so doesn’t accurately capture length of stay after intervention/negative outcomes
I’m not sure how much it would count but the valve they used wasn’t randomised
typically what would be seen as a good length of time for follow up?
Leah AB

7:22 pm
Another weakness is that it states a change in practice for postoperative ventilation, and that it’s centre is increasing Mini Sternotomy over time. This could cause unfavourable results for standard sternotomy if it means fewer patients had a standard sternotomy recently and thus were intubated for longer as per old practice.
Daniel Ahari
Daniel Ahari

7:22 pm
This is a single centre in North America (New Jersey). I’m unsure about the patient demographics in terms of race too. You could argue it’s difficult to generalise the results to populations outside of this sample e.g. black sub Saharan African or Japanese for example. There’s low external validity
As it is a retrospective study they may have been less able to control variables such as expertise of surgeons and standardisation of the procedure
Kirolos Michael
Kirolos Michael

7:23 pm
Danish HaFeez, Very good point. If anyone has noted, the authors suggest that some patients have been in longer, because they were initially admitted with heart failure, treated medically, then had surgery (often these were high risk patients in the CS group). So does this the hospital say reflective ONLY of the different surgical approaches? Probably not
Kirolos Michael
Kirolos Michael

7:23 pm
All great points
Kirolos Michael
Kirolos Michael

7:23 pm
All great points
Leah AB

7:24 pm
Also, in would be useful to compare results to TAVI briefly if you are justifying better outcomes resulting from less invasive procedures.
Kirolos Michael
Kirolos Michael

7:24 pm
How about the difference in STS scores? Do they really account for the differences?
Kirolos Michael
Kirolos Michael

7:26 pm
Leah AB, Great point. TAVI (transcatheter aortic valve implantation) is an alternative method to replacing aortic valves. It would be interesting if this was compared. However, this is a procedure that is usually done by interventional radiologists and this study was more cardiac surgery focused
Daniel Ahari
Daniel Ahari

7:26 pm
What do you mean by that, sorry? “How about the difference in STS scores? Do they really account for the differences?”
Leah AB

7:26 pm
The difference is so small it is arguably not clinically relevant, though it would be good to propensity match this analysis to demonstrate it is only the surgical approach that has caused the difference. This isnt possible on account of the study size.
Danish HaFeez
Danish HaFeez

7:26 pm
Kirolos Michael, I’m wondering- as the authors say they adjusted for demographic characteristics/preoperative conditions- would they have adjusted for sts score?
Kirolos Michael
Kirolos Michael

7:27 pm
Daniel Ahari, so does the STS score account for things like the cardiopulmonary bypass time & the aortic cross-clamp time which was shorter in the MT group?
Americos Argyriou
Americos Argyriou

7:27 pm
I’d say they absolutely confound the results of this study as in essence sicker patients are more likely to be treated with conventional sternotomy and you would expect more intraoperative and post-operative complications in this subgroup. The fact that the STS score is different between groups and there is no matching of patients is a big limitation in my opinion to the results.
Americos Argyriou
Americos Argyriou

7:27 pm
Sorry, a bit late to the conversation.
Patients who underwent MT had a lower STS score that was statistically significant so this could have contributed to their better outocmes rather than the procedure itself
Kirolos Michael
Kirolos Michael

7:28 pm
So, as pointed, no they did not match for the STS scores. The patients with conventional sternotomy had higher STS scores. They probably went for conventional sternotomy in these patients for the better access during surgery
Kirolos Michael
Kirolos Michael

7:29 pm
In terms of mortality & complications, there was no statistically significant difference
Daniel Ahari
Daniel Ahari

7:29 pm
Well to be honest I don’t know what the upper limit of the STS score is – doesn’t that matter?
Kirolos Michael
Kirolos Michael

7:30 pm
but in terms of the cardiopulmonary bypass time & aortic cross-clamp, they argue the STS score doesn’t matter. The just reflect how quickly they were able to do the surgery. So MTs were done a lot quicker than sternotomies
Kirolos Michael
Kirolos Michael

7:30 pm
This is probably because they do a lot more MTs followed by conventional sternotomies
Kirolos Michael
Kirolos Michael

7:31 pm
Mini-sternotomies took longer despite being somewhere in the middle in terms of invasiveness because the surgeons there aren’t used to doing them
Americos Argyriou
Americos Argyriou

7:31 pm
I was thinking this too, the fact that these teams specialize in MT so will carry them out more effectively.
Kirolos Michael
Kirolos Michael

7:32 pm
Daniel Ahari, Yes it does. However in the discussion, they argue that all 3 scores of each group are relatively small anyway
Daniel Ahari
Daniel Ahari

7:32 pm
fair enough!
Leah AB

7:32 pm
Upper limit is 100% i.e. 100% risk of mortality
Kirolos Michael
Kirolos Michael

7:32 pm
They mention all were <3% mortality, indicating the significant difference may not be clinically relevant
Kirolos Michael
Kirolos Michael

7:32 pm
on average that is
Kirolos Michael
Kirolos Michael

7:33 pm
So should we be doing only mini-thoracotomies?
Kirolos Michael
Kirolos Michael

7:33 pm
Any final thoughts/comments/questions before we wrap up?
Leah AB

7:33 pm
Not entirely based on this evidence, though it has its merit in the discussion.
Lily Helston
Lily Helston

7:34 pm
I feel that there is definitely an element of bias that favours the centre’s skillset, so I would hesitate to say yes
Maybe it could be argued that more surgeons should consider trying to become experienced at them
It sounds like they have promising potential, with faster operation times and a reduced length of time in hospital, but as they mention, the other methods have their merits with better views and access in obese patients. It would be important for surgeons to keep CS and MS in their skill set
Americos Argyriou
Americos Argyriou

7:35 pm
With the mortality and negative post-op outcomes in cardiac surgery being relatively low, 500 patients is nowhere near enough to be making inferential results I feel. The question that can be answered here is perhaps the fact that MT is atleast not worse than conventional or the other approach in terms of post-op and short term mortality
Kirolos Michael
Kirolos Michael

7:35 pm
In my personal opinion, I feel this study essentially suggests that at this particular centre, the surgeons are very good & fast at doing mini-thoracotomies those patients stay in hospital for a shorter period of time. But they still prefer conventional sternotomy for patients in whom they want better access
Daniel Ahari
Daniel Ahari

7:35 pm
I think it’s a lot harder to think of strengths than weaknesses (in general to be honest). I agree with what Lily said. I would want to see a systematic review of more centres before I decided.
Kirolos Michael
Kirolos Michael

7:36 pm
I agree with all the comments
It could be argued that in this centre – yes. But a larger, multi-centre review would be helpful for applying the results to a larger population and would also give increased power
More centres across the US and internationally would need to be considered before any definitive changes are even suggested
Danish HaFeez
Danish HaFeez

7:36 pm
Daniel Ahari, agreed- I struggle with strengths too because things can always be better!
Kirolos Michael
Kirolos Michael

7:37 pm
It’s great for the surgeons at this centre demonstrating & auditing their outcomes. I definitely don’t think you can draw any wider conclusions
Kirolos Michael
Kirolos Michael

7:37 pm
Any questions?
Kirolos Michael
Kirolos Michael

7:38 pm
(And yes, a systematic review & metanalysis or even an interventional study would be more ideal)
Leah AB

7:39 pm
No questions from me, thank you for the session!
Daniel Ahari
Daniel Ahari

7:39 pm
Do you recommend any resources for dealing with stats etc
thank you !
Thank you, that was really helpful
Danish HaFeez
Danish HaFeez

7:39 pm
Thank you!
Daniel Ahari
Daniel Ahari

7:39 pm
I felt the paper was pretty straight forward to understand but when it comes to the different tests used I definitely need a reminder
Rox M
Rox M

7:39 pm
Thank you
Thank you!
Thank you!
Lily Helston
Lily Helston

7:39 pm
Really useful session, thank you!
Kirolos Michael
Kirolos Michael

7:39 pm
Daniel Ahari, I’ll find something good for next time
Daniel Ahari
Daniel Ahari

7:39 pm
Otherwise no questions, thanks for the session and for picking a good paper to critique 🙂
Thank you!!
Leah AB

7:39 pm
How to Read a Paper by Trisha Greenhalgh @ Dan !
Kirolos Michael
Kirolos Michael

7:39 pm
Daniel Ahari
Ali Tariq

7:39 pm
Thank you!
Alexandra Brooks
Alexandra Brooks

7:39 pm
Really interesting paper and useful session, thanks
Kirolos Michael
Kirolos Michael

7:40 pm
Daniel Ahari
Thank you!
Daniel Warrington
Daniel Warrington

7:40 pm
First journal club, was interesting. Thank you
Kirolos Michael
Kirolos Michael

7:40 pm
Daniel Ahari
Kirolos Michael
Kirolos Michael

7:40 pm
I will be very grateful if everyone could complete this feedback form:
Kirolos Michael
Kirolos Michael

7:40 pm
Kirolos Michael
Kirolos Michael

7:41 pm
Beth will distribute on the group
Kirolos Michael
Kirolos Michael

7:41 pm
Thanks for everyone for completing the pre-journal club form
Kirolos Michael
Kirolos Michael

7:42 pm
I think it may have been lost. This paper was selected by a journal club member. If anybody wants to suggest papers, they are more than welcome to email me at kirolosmichael@gmail.com
Kirolos Michael
Kirolos Michael

7:43 pm
Next session will be on vascular surgery