CRY Research Fellow, Dr Saqib Ghani, had the article ‘Pre-participation cardiovascular screening in athletes: when and how?’ published in the journal ‘Cardiovascular Medicine’, January 2012.
CRY Communications Officer, Mair Shepherd, caught up with him on his return flight from a CRY screening clinic in Northern Ireland to find out more.
- What was the article about?
This article was mainly for educational purposes to raise awareness and help summarise the data on pre-participation screening for other physicians and cardiologists. It gives an overview of the evidence we have regarding cardiac screening in athletes and young healthy individuals in order to reduce the risk of sudden death. We covered the main issues regarding screening and gave an overall summary with our own perspective at the end of this article.
- Why did you write this article?
It was a result of a lecture that Professor Sanjay Sharma delivered at the annual meeting of the Swiss Society of Cardiology in June 2011 in Basel. Following his lecture the society invited us to write this review article in their cardiac journal to educate other physicians.
- What aspects of screening did you cover?
We covered various aspects around cardiac screening in healthy individuals and athletes. We looked at the different causes of sudden death and the current screening protocols around the world, particularly the ones which are in practice in the United States of America and in Italy. We also discussed various other issues in favour of and against screening. Over time there has been a lot of discussion to promote screening but it’s a slightly controversial issue, particularly with the use of ECG as a screening tool, and we also looked at the evidence supporting ECG and how the use of ECG has been proven to be more effective over time. We also gave our own personal perspective based on what we do in the United Kingdom, with support from a charitable organisation called Cardiac Risk in the Young.
- You mentioned the protocols used in the USA and Italy. Could you tell me more about what these protocols are?
I’ll start with Italy actually. Since 1979, a mandatory national cardiac screening programme has been in existence in Italy for all athletes at all levels and that includes a health questionnaire, physical examination and 12-lead electrocardiogram. Every athlete has to undergo this screening before they participate in any kind of sport and, so far, Italy is the only country where it is mandatory for athletes to undergo this kind of screening. This model has been adopted in various other European countries and endorsed by various cardiac and sporting bodies like European Society of Cardiology, International Olympic Committee, FIFA and UEFA. In contrast, in America there is a screening programme in existence – it’s not a mandatory national programme – but the main difference from the Italian model is that they do not include an electrocardiogram. The American programme appears to be cheap and pragmatic and easily applicable, however it has a lower diagnostic yield and it has been shown from various studies that by including ECG as a part of screening, as is done in Italy and some of the other European countries, the diagnostic yield is significantly improved.
- So the American screening programme is a voluntary programme? And is that just open to athletes or is the screening available to anyone?
It is a voluntary programme and as I said it’s not a national programme, it’s conducted in various areas by different organisations – different sporting clubs – so it’s not like Italy where it’s national. It’s a state sponsored programme and it’s available to the general public as well, not only to athletes. And the same applies to all the screening programmes in Europe, although they are focussed more on sports and athletes but they are actually available to the general population and the Italian data, particularly, is collected from a non-selected population. Obviously, though, most of them are going onto an athletic career.
- What are the benefits of each of the different types of programme that are run in America compared to that in Italy?
The main purpose of cardiac screening is to identify individuals with silent cardiac disorders which are implicated with sudden death. Now, physicians and health professionals around the world support screening and they all advocate young people to get screened, but the difference is in understanding which programme is the most effective, most efficient and most cost effective.
So, as I said in my previous question, the American programme includes a health questionnaire and physical examination without ECG. Obviously, because ECG is not included, you don’t need experts to interpret the ECG, therefore it’s easily applicable, cheaper to do and does not raise a lot of issues about cost effectiveness. On the other hand, the diagnostic yield will be low because there are a lot of cardiac conditions which cannot be identified in the absence of ECG, particularly heart rhythm disturbances. In addition, some of the cardiomyopathies or heart muscle disorders may also remain asymptomatic, so the athletes may not have any symptoms at all. Therefore, the ECG could be the early sign or the only abnormality which could hint towards an underlying diagnosis.
Moving onto the Italian study protocol, the inclusion of ECG has shown to be effective – not only is the diagnostic yield improved – but over the 30-year screening period they have demonstrated a reduction in the incidence of sudden death by approximately 89%, by identifying people at risk with these conditions and disqualifying them from sport. So it is beneficial but, on the other hand, a lot of athletes have some changes on the ECG because of athletic cardiac remodelling and that can raise concerns because of the high number of tests required to be absolutely sure that the heart is normal. That requires funding; there are cost implications, there are logistic implications, so it’s not easy to apply on a universal scale. You need experts to be able to interpret these ECGs and advise accordingly. But what goes in favour of this screening is that over time, with better understanding of the athlete’s heart, the impact of false alarms or false negative results has gone down in expert settings so fewer athletes require more investigations and the diagnostic yields are higher.
- What’s the actual controversy surrounding screening that you mentioned earlier?
As I mentioned earlier, health physicians on both sides of the Atlantic support and endorse cardiac screening, even around the world all the sporting organisations support and encourage screening for young healthy athletes, but the controversy is around the most efficient and cost effective methodology. This controversy has led to two different kinds of screening protocol that I’ve mentioned before – the one practiced in America where ECG is not included compared to the one in Italy and other parts of Europe where ECG is a part of screening protocol. So this is the main controversy and the discussions which galvanise or encourage screening are issues around sudden death in young people. These athletes and young people are not expected to die suddenly so these events are very tragic – they live in memories for a long time, they have a huge impact on the general population, families, friends and team members, and the media covers these events, raising more awareness in the community. Such events then galvanise discussions in support of screening. On the other hand, because of issues around funding, cost effectiveness and logistics of wide-scale screenings there have been arguments against the use of ECG as a universal screening tool.
- You mention in the article the problem of false positives, what is a false positive?
When someone undergoes a cardiac screening, and particularly let’s say screening which involves an ECG, an ECG sometimes can raise some concerns about a potential diagnosis. In order to confirm if there is anything wrong with an individual’s heart they sometimes require more tests. Usually the first test we do is an echocardiogram, which is an ultrasound scan of the heart, and sometimes more tests can be needed but if an ECG appears to be abnormal and further tests show that there is no evidence of any underlying disease, then those slight abnormalities on the ECGs reflect as false positive results, or in other words false alarms.
- So I imagine having a false positive can cause concerns for those being screened. Is there a way these false positives be reduced?
With better understanding of the athlete’s heart, and what on the ECG may represent a normal finding in an athlete, these false positives are likely to reduce with time. Over the last few years we have seen the reduction in the number of false positives. Looking at some previous studies, false positive rate has been documented to be as high as 10-30% which means every 2 or 3 people out of 10 would require further tests on the basis of their ECG. This is obviously concerning because it will be very costly, but if you look at the ECG criteria in 2005 and compare it with more recent guidelines in 2010, and I’m talking about the guidelines on behalf of the European Society of Cardiology, they are slightly amended and include some of the ECG parameters which were previously labelled as abnormal in the normal category. To be more specific, I’m talking about chamber enlargement because athletes’ hearts are slightly enlarged due to exercise and this can reflect on the ECG as what we call left ventricle hypertrophy. Now, with recent guidelines, in the presence of such ECG changes it does not raise any concerns and they are expected to be normal findings in athletes. For example, a study from an American group in 2010 demonstrated that by comparing the previous and the new guidelines on a similar cohort of athletes the false positive was reduced from 16% down to 10%. That 6% reduction was predominantly due to this single ECG parameter which has now been reclassified. In our experience, there are some other features which currently exist on the guidelines which sometimes warrant further tests which in our studies on athletes over the last few years have not shown any significant abnormality on further tests so we think the guidelines, although have improved, they’re not replete and can be improved further with more research.
- By reviewing the various data and previous studies what did you eventually come to conclude?
On the basis of the data available so far, most of which comes from the Italian mandatory screening programme, we concluded that pre-participation cardiac screening using an ECG is effective in identifying cardiac disorders and it has resulted in the reduction of incidence of sudden cardiac death. Major organisations and sporting bodies support screening and they advocate athletes undergoing one or the other form of cardiac screening. Recently false positive rates have also been on the decline and therefore we think that if conducted in an expert setting cardiac screening with ECG can be effective and more research is required to make it widely applicable to different ethnicities and various other members of the general population, in addition to athletes.
- Is more data required?
More data is required. The vast majority of data available so far is from European and American studies which include mostly white or Caucasian athletes or members of population. We now know that in individuals and in athletes belonging to Afro-Caribbean ethnicity the ECG findings and echocardiographic findings can be slightly different compared to Caucasians if they take part in the same sport over the same period of time. Therefore, we believe that ethnicity also has an impact on how an athlete’s heart develops. This sometimes offers some diagnostic challenges as some changes in the ECG in Caucasians would be considered abnormal, but in Afro-Caribbean individuals they may be a normal ethnic variant which can lead to confusion and difficulty in managing these people. Therefore, wider larger scale studies are required in individuals from different ethnicities, not just Afro-Caribbeans, probably also Asians, Chinese, in order to understand the ethnic impact on a wider scale so that universal pre-participation screening programmes can be made easy to implement, such that the cost implications are as little as possible and the best available data is available for future reference.
- How could this sort of data be gathered?
In order to get more data from multiple ethnic origins, in other words athletes from other ethnic backgrounds, I think more studies should be done in countries with a multi-ethnic population. Young people from different ethnicities should be encouraged to come forward and undertake cardiac screening and that will generate data which will hopefully help in future, enabling screening to be implemented on a wider scale.
- You mentioned screening in the general population earlier, is this something that should be available to everyone?
With cardiac screening, particularly to identify people at risk from sudden cardiac death, we are looking for conditions which are normally inherited or congenital and therefore we recommend screening in individuals aged between 14 and 35. At ages less than 14 there is a chance that some of these cardiac disorders may not be apparent on cardiac evaluation because usually the heart develops into an adult heart around puberty. Also in individuals less than 14 years of age there is a chance of increasing the false positive results. When I talk about the upper age of 35, the reason behind that is because of the various causes of sudden death. In individuals aged more than 35, the most common cause of sudden cardiac death is premature coronary artery disease, where there is narrowing of the blood vessels supplying the heart muscle, and that can not be identified at a routine resting ECG therefore we might be offering false reassurance to those individuals. On the other hand the conditions which cause sudden death in younger individuals (less than 35) can be identified on the ECG and therefore we recommend screening in this age group.
- Would screening identify every potential cardiac abnormality?
Whereas ECG is very useful in diagnosing the majority of inherited cardiac conditions, no screening programme is foolproof. Similarly a screening programme based on ECG has a potential of missing a few conditions, particularly heart valve abnormalities and, as I already mentioned, premature coronary artery disease. In addition, there is also a condition where the coronary arteries are not blocked but they originate from a different area from the expected site of origin and that can lead to symptoms and sudden death and these things can not be picked up on the ECG. In addition, some of the heart muscle disorders may not manifest until later in life or they may be present in a very mild form in which case the ECG can be normal. So there is a small false negative rate with these screening events as well, but overall the majority will be identified.
- If an athlete was to experience a cardiac arrest, what could be done to increase their survival?
Whereas screening is a preventative measure to identify people before they experience any untoward event or sudden cardiac arrest, we have witnessed or heard about individuals collapsing on the pitch whilst playing sports. When this happens it is very important to treat this as soon as possible. If the heart rhythm goes into a fatal rhythm disturbance we can use devices called automated external defibrillators which should be available in all sporting organisations and sporting venues. And if we can minimise the time between collapse and shock delivered the survival rate can be improved. The availability of the defibrillator is not the only solution, in addition to being available there should be an emergency response plan in place which should incorporate personnel training, regular review of the policies, an effective communication system, and training of individuals to be able to use this defibrillator and the target should be to deliver a shock within 5 minutes of someone collapsing, if anything like this happens in a sporting venue.
