This remains a difficult medical challenge for preventing sudden athlete heart death , usually defined as an unexpected natural death from a heart attack within an hour of the onset of collapse symptoms, excluding additional time on mechanical life support. (A broader definition of sudden death is also used, but not usually applied to athletic situations.) Most causes are associated with congenital or acquired cardiovascular disease without symptoms recorded before the fatal event. The prevalence of each single linked condition is low, probably less than 0.3% of the population in the athlete age group, and the sensitivity and specificity of the general screening test leave much to be desired. The single most important predictor is fainting or almost fainting during exercise, which should require explanation and detailed investigation. Victims include many famous names, especially in professional football, and close relatives are often at risk for the same heart problem.
Video Sudden cardiac death of athletes
Incident
Sudden cardiac death occurs in about one per 200,000 young athletes per year, usually triggered during competition or exercise. Victims are usually male and related to soccer, basketball, ice hockey, or American football, reflecting the many athletes participating in this sustained and heavy sport. For a normally healthy age group, the risk appears to be enormous in competitive basketball, with sudden cardiac death rates as high as one per 3,000 per year for male basketball players in the NCAA Division I. This is still far below levels for the general population. , estimated at one per 1,300-1,600 and dominated by parents. However, a population of the United States will experience sudden cardiac death of a competitive athlete by an average of one-third days, often with significant local media coverage raising public attention.
Maps Sudden cardiac death of athletes
Cause
Sudden cardiac deaths of 387 young American athletes (under age 35) were analyzed in a 2003 medical review:
While most of the causes of sudden cardiovascular death are associated with congenital or acquired cardiovascular disease, the exception is the cordis komotio, in which the heart is structurally normal but the loss of a potentially fatal rhythm occurs due to an accidental blow to the chest. The mortality rate is around 65% even with rapid CPR and defibrillation, and over 80% without.
Age 35 serves as an approximate limit for possible causes of sudden cardiac death. Before the age of 35 years, congenital abnormalities of the heart and blood vessels predominate. This is usually asymptomatic before a fatal event, though not always the case. Congenital cardiovascular deaths are reported to occur disproportionately among African-American athletes.
After age 35 years, coronary artery disease dominates (80%), and this is true regardless of the fitness level of the former athlete.
Screening
Screening athletes for heart disease can be a problem because of the low prevalence and inaccurate performance of the various tests that have been used. Nevertheless, the sudden death among healthy-looking individuals attracts much public and legislator attention because of its visible and tragic nature.
For example, the Texas Legislature used US $ 1 million for a statewide screening demonstration study across the state in 2007. The study used a combination of questionnaire, examination and electrocardiography for 2,506 student athletes, followed by echocardiography for 2051 of them, including each student with findings abnormal of the first three steps. The questionnaire itself marks 35% of students as potentially at risk, but there are many false positive results, with the actual disease being confirmed in less than 2%. Furthermore, a large number of positive screen students rejected recurring recommendations for follow-up evaluation. (Individuals who are conclusively diagnosed with cardiovascular disease are usually told to avoid competitive exercise.) It should be emphasized that this is a single pilot program, but it indicates a problem associated with large-scale screening, and is consistent with experience in other fields. locations with a low prevalence of sudden death in athletes.
Genetics
Cardiomyopathy
Cardiomyopathies are generally inherited as autosomal dominants, although recessive forms have been described, and enlarged cardiomyopathy may also be inherited in an X-linked pattern. Consequently, in addition to the tragedy involving an athlete who succumbs, there are medical implications for close family. Among family members of index cases, more than 300 causative mutations have been identified. However, not all mutations have the same potential for severe outcomes, and there is no clear understanding of how these mutations (which affect the same myosin protein molecule) can cause dramatically different clinical characteristics and outcomes associated with hypertrophic cardiomyopathy (HCM ). ) and dilated cardiomyopathy (DCM).
Because HCM, for example, is usually an autosomal dominant feature, every child of a HCM parent has a 50% chance of inheriting a mutation. In individuals without a family history, the most common cause of this disease is the "de novo" mutation of a gene that produces a heavy chain? -myosin.
Channelopathies
Sudden cardiovascular death may be associated with cardiovascular disease or cordic comotype, but about 20% of cases do not show clear cause and remain undiagnosed after autopsy. Interest in "autopsy-negative" deaths is centered around "ion channelopathies". These electrolyte channels are the pores that regulate the movement of sodium, potassium and calcium ions into the heart cells, collectively responsible for creating and controlling electrical signals that regulate the heart's rhythm. Abnormalities in this system occur in relatively rare genetic diseases such as Long QT syndrome, Brugada syndrome, and ventricular polymorphic catecholaminergic tachycardia, all associated with sudden death. As a result, sudden autopsy-negative cardiac death (no identified physical abnormalities) may consist of a larger section of channelopathies than previously anticipated.
a beneficial connective tissue disease
Heritable connective tissue disease is rare, each disorder estimated at one to ten per 100,000, of which Marfan syndrome is the most common. This is carried by the FBN1 gene on chromosome 15, which encodes the fibrillin-1 connective protein, inherited as a dominant trait. This protein is essential for the synthesis and maintenance of elastic fibers. Because these fibers are extremely abundant in the aorta, ligaments, and ciliary zones of the eye, these areas are among the most severely affected. Everyone has a pair of FBN1 genes and, because of the dominant transmission, those who inherit an affected FBN1 gene from one parent will have Marfan syndrome. Although most commonly inherited as an autosomal dominant, there is no family history in 25% of cases.
Recruitment practices aimed at attracting extraordinarily high athletes with a very wide range of arms (characteristic of Marfan syndrome) can increase the prevalence of syndromes in sports such as basketball and volleyball.
DNA testing
Once the disease-causing mutation has been identified in the case of the index (which is not always achieved conclusively), the primary task is genetic identification of carriers in the pedigree, a sequential process known as "cascade testing". Family members with the same mutation may indicate the severity of different diseases, a phenomenon known as "variable penetration". As a result, some may remain asymptomatic, with little evidence of lifelong illness. However, their children remain at risk of inheriting the disorder and potentially becoming more severe.
Famous cases
These athletes, in alphabetical order, experience sudden cardiac death at the age of 40. Their determination is determined by reliable sources in other Wikipedia articles.
See also
- Heart Risk in Adolescents (British charity)
- List of athletes who died during their careers
References
Source of the article : Wikipedia
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