Authors: William Niven, Barbra Backus, Michael Weinstock, Amal Mattu / Editors: Charlotte Davies, Liz Herrieven / Codes: CP1, SLO1, SLO2, SLO3 / Published: 13/08/2019

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The content you’re about to read or listen to is at least two years old, which means evidence and guidelines may have changed since it was originally published. This content item won’t be edited but there will be a newer version published if warranted. Check the new publications and curriculum map for updates

In 1887, Dr Ludwik Zamenhof, an ophthalmologist, developed an artificial language incorporating the linguistic features from the major Indo-European languages. He called this language ‘Esperanto’ and hoped that it would enable people to ‘overcome the natural indifference of humankind’ ushering in a new era of international peace and harmony.

Zamenhof understood the importance of students of Esperanto being able to identify aspects of their mother tongue – a Latin-based grammar was supplemented by an amalgam of Germanic, Romance and Slavic words – and it is here that we can now segue into the similarities between Esperanto and chest pain risk stratification tools! For it is my opinion that for any risk tool to be widely adopted, it needs to resonate with the ‘grammar’ of the condition to which it applies and in the case of ischaemic chest pain, that would be history, ECG and cardiac biomarkers.

With chest pain presentations accounting for 6% of all emergency department attendances in the UK it is not surprising that the number of chest pain risk stratification tools has grown so rapidly – there are now over 20 as identified by a recent systematic review. Faced with such a choice of decision aids and the ever-expanding evidence base, emergency physicians could be excused for struggling to pick a winner! However, I have found two resources very useful in helping to navigate the way. The first is from St Emlyns entitled ‘Getting your chest pain evaluation right‘. The second is a conversation between Rick and Barbra Backus, the original developer of the HEART Score about the future of chest pain risk stratification. In many respects this blog is merely rehashing and emphasising the excellent points that have already been made. The principal message was that chest pain risk stratification the decision aid you pick matters less than the dangers of trying to manage a patient without one…

My personal preference, as you may have gathered from the title of this post, has been to use the HEART Score. The factors that have influenced my choice are:
– it contains the ‘grammar’ of chest pain risk stratification
– the system is intuitive and employs a memorable mnemonic
– it is simple, easy to calculate and does not require a computer
– there is a strong evidence base that speaks to its validity and generalizability in different contexts

As such I believe it is a good candidate for creating a ‘common language’ that facilitates communication between doctors and helps patients to better understand the risks posed by ischaemic chest pain.

There are subtleties to the HEART Score and risk stratification tools in general. Once validated, there are three main issues to address:
– Will the adopting clinician apply this tool to the patient population for which it is intended? The chances are that a young, post-partum woman presenting with right leg swelling and recent onset chest pain will ultimately not thank you if you employ the HEART Score to guide decision making, stratify her as ‘low risk’ and discharge her home?
– Will the clinician be able to use the risk tool correctly?
– Will different clinicians using the same tool on the same patient end up with similar conclusions?

In a cross sectional study, we showed that junior and senior doctors and nurses calculated similar HEART Scores on the same patient, but that the ‘history’ is the least reliable element of the score. Sometimes, this is because patients tell their story differently to subsequent health care professionals. Thus the inherent subjectivity of the history combined with the fact that history is only a moderately useful predictor of acute coronary syndrome in the ED presents us with the uncomfortable question of whether we should rely on it at all.

The answer is neither a binary yes or no – as we are still heavily reliant on history to form a differential and decide whether the chest pain is likely to be – for example – cardiac, pleuritic or musculoskeletal in nature. These same studies showed that senior clinicians performed better than their junior colleagues when deciding whether chest pain was ischaemic or not. Whether this is the result of good teaching, improved gestalt, experimental processing or just knowing ‘how’ to ask the questions is a fascinating mystery.

However, leaving aside this complexity, there are certain aspects of the history that have been shown to be valuable in the prediction of ischaemic chest pain. These include pain that radiates to the right arm or to both arms, pain that is worsened by exertion, pain that is associated with vomiting, and pain that is associated with sweating. I, for one, was not taught about the value of pain radiating to the right arm or associated vomiting as a medical student, and anecdotally, I still do not feel that this is the case with a significant proportion of the other clinicians with whom I work! Yet, as with many things in medicine, a lag remains between the publishing of new evidence and its widespread adoption in practice.

The sharing of knowledge, and a clarification on how to calculate the HEART Score has been the focus of a recent project. There are subtleties that require explanation in the scoring of the history, ECG and risk factors elements. Furthermore, in an era of high sensitivity troponins there are questions as to how we interpret the assay, given its greater sensitivity for acute coronary syndrome. Along with Dr Backus, we decided in early 2018 to create a teaching video that would address some of these issues. The original shoot was ‘organised’ with just 2 weeks of preparation and no previous filming experience. However, despite all odds it happened and the first video, put together by our cameraman Pavel Kvatch, was a better demo than we thought possible! A link to the original video can be found here.

However Barbra and I felt that we could do better – there was more to be said and what we had said could be expressed more clearly. We also felt some aspects of the HEART Score, particularly the ‘history’ element, would benefit from being explained and illustrated in a range of different languages. For the next set of videos, we consulted widely across different health care systems and countries and were fortunate enough to have the input of Drs Amal Mattu and Michael Weinstock from the USA as well as Dr Youri Yourdanov and Felix Lorang from France and Germany respectively. You can view our latest effort here.

We have now shot videos in eight different European languages. Plans are already made for future videos in Arabic, Hindi, Mandarin Chinese and Russian. We plan, simultaneously, to create content for patients that will explain the concepts behind chest pain risk stratification and assist them, in the interests of shared decision-making, to take a more active role in their on going care.

Our goal to create a ‘common language’ around chest pain risk stratification is not yet complete. Like other languages, it is both an organic and iterative process that will adapt with new data and new technology. The HEART Score of tomorrow may look different from yesterday; causing excitement rather than consternation. The meaning of Esperanto is ‘the one who hopes’. In this regard, we share the sentiments of Dr Zamenhof and Charles Dickens because, for the HEART Score, we have great expectations…

For further RCEMLearning resources on chest pain, look the curriculum linking here.

References

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3. Body R. Getting your chest pain evaluation right: #UMECS16 [Internet]. 2016 [accessed June 5th 2019].
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