The results showed 24 documented events of sudden death or cardiac arrest events among competitive athletes during the years 1985 through 2009 – eleven occurring before the 1997 legislation, and 13 after it. The respective averaged yearly incidence during the decade before and the decade after the 1997 legislation was 2.54 and 2.66 events per 100,000 person years, respectively (p=0.88).

The authors assert that any drop in sudden death rates observed after introduction of ECG screening most likely results from the unusually high rates which typically inspire such legislation in the first place. “Only when one extends the comparison of sudden death rates to include the decade that preceded the enforcement of screening…does one realize that this mortality reduction is the result of a large variation in mortality rates over longer periods of observation,” they note.

In an accompanying editorial² Dr Alfred Bove, Temple University School of Medicine, emphasises the danger of variant but healthy ECG results leading to unfair disqualification. Such screening, he claims, can lead to a “high number of false positive diagnoses of cardiomyopathy. The atypical echocardiography findings in an athlete are affected by the size of the athlete and by the degree and type of training”.

Dr Bove continues: “The concern is that many athletes would be disqualified based on false positive ECG findings, and we do not at present have an inexpensive method for more accurate screening”. Steinvil et al conclude that the costs of mandatory screening are so high, both for the finances of participating nations and the personal prospects of disqualified athletes, that “it is reasonable to request additional proof that such a strategy actually saves lives”.

References

1. Steinvil A, Chundadze T, Zeltser D et al. Mandatory Electrocardiographic Screening of Athletes to Reduce Their Risk for Sudden Death: Proven Fact or Wishful Thinking? J Am Coll Cardiol 2011:57;1291–6.
2. Bove AA. Making or Breaking Athletic Careers. J Am Coll Cardiol 2011:57;1297–8.

Dr Joaquín Lucena, MD PhD, Head of the Forensic Pathology Service at the Institute of Legal Medicine (Seville, Spain) who led the study, said: “Our findings show that cocaine use causes adverse changes to the heart and arteries that then lead to sudden death.”
 
Dr Lucena and his colleagues found that median levels of cocaine in blood or urine were 0.1 and 1.15 mg/L respectively, with a range that varied widely but which depended on a number of factors related to the drug itself (how it was taken, how people’s bodies processed it and what other substances were taken at the same time), and to the people themselves (body mass index, acute or chronic use of the drug, other underlying health issues, age and sex).

They wrote: “Any amount of the drug can be considered to have the potential for toxicity due to the fact that some patients have poor outcomes with relatively low blood concentrations, whereas others tolerate large quantities without consequences.”
 
The researchers also found that 81% of the men who died after cocaine use also smoked, and 76% had drunk alcohol. Ethanol, the intoxicating ingredient in alcoholic drinks, enhances the “high” obtained from cocaine while minimising the subsequent “low”. However, both smoking and alcohol are associated with heart disease and Dr Lucena said: “The combination of cocaine with either or both of these habits can be considered as a lethal cocktail that promotes the development of premature heart disease.”
 
The study is the first to investigate the prevalence of cocaine-related sudden deaths in such a detailed and methodical way. The authors highlight the importance of this method of studying sudden deaths.
 
“For the correct diagnosis of the sudden death, especially in young adults, it is important to use a uniform autopsy protocol, including a toxicology investigation of the blood and urine for illicit drugs,” said Dr Lucena.

“Cocaine abuse is a growing public health issue in Europe and we can only monitor its prevalence by performing these detailed autopsies whenever someone dies suddenly.”
 
In their study, the authors wrote: “The estimated number of COC [cocaine] consumers is about 12 million Europeans with an overall prevalence of 3.7% of the total adult population (15-64 years). Ever in lifetime experience of COC is reported by more than 5% of the total adult European population in three countries: UK (7.7%), Spain (7.0%) and Italy (6.6%). The prevalence of use of COC is higher among young adults (15-34 years), with around 7.5 million young Europeans (5.4% on average) estimated as having used it at least once in their lifetime. In the year 2007, an estimated 3.5 million (2.4%) European young adults have used COC, with the highest prevalence levels, of over 3%, being found in Spain, Italy and the UK.”
 
Dr Lucena said: “As the estimated number of European young adults cocaine consumers is similar in Spain, UK and Italy, there is no reason to consider that the cocaine-related sudden death in UK and Italy would be different to what we have found in our research in south-west Spain.”
 
To put the rates of sudden deaths in context, he added: “According to our experience in the Forensic Pathology Service at the Institute of Legal Medicine, the rate of cocaine-related deaths per year in Seville, is roughly half the number of people who die suddenly from haemorrhagic stroke.”

Professor David Hillis and Professor Richard Lange, chairman and executive vice chairman respectively of the Department of Medicine at the University of Texas Health Science Center (San Antonio, USA), who were unconnected with the work, wrote an editorial to accompany Dr Lucena’s paper. They reported that the prevalence of cocaine use varied in Europe from 0.7% in Romania and Lithuania to 12.7% in the UK, but this was likely to be an under-estimate.
 
They agreed that uniform protocols were required for post-mortems on victims of sudden death, including toxicological examination of the blood and urine for illicit drugs. “Until these are accomplished, the prevalence of cocaine and other illicit drug use will be underestimated, and cocaine-related complications will not be recognized,” they wrote. “Physicians should consider the possibility of cocaine abuse in a young individual with cardiovascular disease or sudden death, especially in those without traditional risk factors for atherosclerosis. Finally, the notion that recreational cocaine use is ‘safe’ should be dispelled, since even small amounts may have catastrophic consequences, including sudden death.”

References

1. “Cocaine-related sudden death: a prospective investigation in south-west Spain.” European Heart Journal. doi:10.1093/eurheartj/ehp557.
[2] “Sudden death in cocaine abusers.” European Heart Journal. doi:10.1093/eurheartj/ehp503.

Dr Mary Sheppard, of the Royal Society of Medicine’s Pathology Section, and a consultant at the Royal Brompton Hospital, London, who is a leading expert in SCD, argued “A DNA sample from a person who has died suddenly could provide a whole genome picture which might benefit relatives potentially at risk from genetic conditions, such as Long QT Syndrome; Brugada Syndrome; inherited cardiomyopathies, etc. If coroners routinely requested consent from the family to retain material for DNA testing at autopsies we would be able to find out far more about how the person died and possibly prevent other deaths in the same family.”

It is currently illegal to retain tissue for DNA testing without consent of the deceased’s relatives except in forensic cases.  Dr Paul Brennan, a Clinical Geneticist and Clinical Lead for Cardiac Genetics for the Northern Genetics Service, argued for a change to the current situation in his presentation at the meeting. He said,

“The coroner’s remit is to establish cause of death. This does not currently involve DNA analysis so there is no imperative for the coroner to request storage of DNA from the deceased person. There is, however, a need to alert surviving relatives to the possibility that their relative may have died from an inherited heart problem, in which case genetic testing in the deceased is often necessary. Ideally, there should be one part of a coroner’s form which deals specifically with consent for the pathologist to retain tissue for DNA extraction and storage. Until then, I would urge pathologists who haven’t had the opportunity to obtain consent, to think about taking these tiny tissue samples – usually a spoonful of blood or a cubic centimetre of spleen tissue – and then ask the relatives for consent. If consent is not given, the tissue must, by law, be destroyed. But if it is not even taken in the first place, a huge potential benefit is lost.”

The tissue required for DNA extraction and genetic testing needs to be taken at autopsy in order to provide the information needed.  Delay can mean that the specimen cannot provide the important information needed. “There’s only a short window of opportunity after a person has died.  Once that time has passed a perfect – perhaps life-saving – opportunity is missed,” said Dr Brennan.

At present, all close relatives of a victim of SCD should be offered medical screening tests to see if they display signs of an inherited heart problem. This approach can, however, fail to detect problems that a genetic test can help to reveal. The whole idea is to detect these conditions before they cause serious complications – including sudden death. Dr Brennan argued that routine retention and subsequent analysis of the specimens would have negligible cost implications as the cost of genetic testing was usually provided for under specialist commissioning arrangements.

He added, “There has been a lot of discussion about DNA being retained in criminal cases. It seems ridiculous that we don’t retain tissue in a situation where it could actually save lives.”

The consent of the next-of-kin is not required for a coroner’s post-mortem.  Coroners seek to establish the medical cause of death, usually by post-mortem.  Earlier this year, Dr Michael Powers QC, an expert in coroners’ law, argued that a change in the law was needed so that coroners could order tissue to be tested for variant Creutzfeldt-Jacob disease. Dr Powers believes that, currently, ordering the tests ‘is a function which is outside the coroners’ statutory authority’, as they have a responsibility only to discover the causes of an individual’s death.

The Human Tissue Authority has guidance on the matter of consent for DNA testing (see, in particular, paragraph 155).

Dr Mont reports that atrial fibrillation is more frequent in middle-aged individuals who formerly took part in competitive sports and continue to be active, or simply in those involved in regular endurance training without having actually participated in competitive sports. “So we have to look at the effects of endurance or athletic training with a more open view,’ says Dr Mont.

However, he adds that the cost-effectiveness of routine pre-participation screening in a broad population of athletes and endurance sports participants has not yet been clarified.

What does seem clearer, however, is that long-term endurance sport participation may well increase the incidence of cardiac arrhythmias, particularly atrial fibrillation, atrial flutter, sinus node dysfunction, and right ventricular premature beats. “Given the fact that an increasing number of individuals engage in regular endurance sports,’ says Dr Mont, “it is certainly of great interest to define which recommendations for sport should be implemented in an individual patient, and how best to manage arrhythmias in participants.’ Atrial fibrillation is the most common arrhythmic condition, and sudden cardiac death remains a risk.

Three papers presented at the Europace 2009 congress by Dr Mont’s group reflect the research effort now being directed towards sports cardiology and the prevention and treatment of rhythm disorders.

1. Efficacy of the circumferential pulmonary vein ablation of atrial fibrillation in endurance athletes. CPVA is a recently introduced technique which identifies the signals causing the atrial fibrillation and isolates their source in the pulmonary veins from the left ventricle of the heart. The technique has been successfully used in routine patients with atrial fibrillation and, according to new data presented here in Berlin, is now as effective in AF secondary to endurance sports as in other causes. A series of 182 patients in Dr Mont’s Barcelona clinic found that freedom of arrhythmias following CPVA was similar in the sports participants as in the regular patients. Left atrial size and long-standing atrial fibrillation were the only independent predictors for arrhythmia recurrence after the treatment, not sports participation.
2. Deconditioning reverses expression of cardiac fibrosis markers in an animal model of endurance training. A more basic science study from Dr Mont’s group in Barcelona also suggests that those with a history of arrhythmias following endurance training may benefit from a period of “deconditioning’ following their efforts. The suggestion follows a study in animal models which found that markers of cardiac fibrosis in rats whose treadmill exercise was followed by a period of inactivity returned to control levels. Endurance exercise causes cardiac structural changes, including atrial and right ventricular fibrosis – and this fibrosis may play a role in the development of arrhythmias. Although it has been noted that the athlete’s heart regresses after inactivity it is not known if the sport-induced atrial and right ventricular fibrosis also reverses after deconditioning. This study suggests that it does and that a period of inactivity might be of benefit in those with a history of fibrillation.
3. Losartan attenuates heart fibrosis induced by chronic endurance training in an animal model. Just as inactivity after training may inhibit cardiac fibrosis in animal models, a similar study suggests that the anti-hypertensive drug losartan prevents the heart fibrosis induced by endurance exercise. The anti-fibrotic effect of losartan, an angiotensin type-II receptor antagonist, appears to be mediated suppression of angiotensin II-induced proliferation of fibroblasts. Again, mark