Cardiac arrest at rest and during sport activity: causes and prevention

In the Western Countries, cardiovascular diseases are still the most frequent cause of death, which is often sudden. Sudden death (SD) in the young population occurs at a rate of 1/100 000/year and carries a profound social impact both for the young age of the victims and the unanticipated occurrence. Physical effort is a triggering risk factor, in fact SD occurs three times more frequently in athletes than in non-athletes. The screening for sport activity fitness can identify apparently healthy subjects carrying a silent abnormality able to trigger sudden cardiac death during sport activity, thus the fitness screening could be lifesaving. The spectrum of cardiovascular conditions identified at post-mortem examination is quite extensive, and include: coronary, myocardial, valvular diseases, as well as conduction system abnormalities. In 20% of the cases, the heart is normal, and sudden cardiac death is ascribed to ionic channel disease. The diagnosis of cardiomyopathy is possible with the integration of electrocardiogram and echography, thus decreasing significantly the occurrence of SD of athletes in Italy, but early diagnosis of coronary artery disease still remains challenging. The best strategy to further decrease sudden cardiac death during sport activities consists in combining early diagnosis with widespread availability of defibrillators on site.