**6. Circumstances of SCD and prodromal symptoms**

When analyzing the circumstances of SCD in young athletes, it was observed that in 83% of cases, SCD occurred during or immediately after exercise, and only 17% was not associated with any physical activity [6]. In some cases, it was possible to obtain the medical histories of the victims or data on the presence of some

specific diseases or conditions or potential symptoms preceding the fatal episode. In 60 squash players who died suddenly, Northcote et al. [20] were performed an analysis of prodromal symptoms before death. In a decreasing order of symptom frequency, athletes with sudden deaths complained of chest pain, increasing fatigue, non-specific gastrointestinal disorders, a burning sensation in the heart area, feeling short of breath, pain in the ears or neck, non-specific malaise, upper respiratory tract infections, dizziness and/or palpitations, and severe headache. Five of the victims (8.3%) had no significant symptoms before death. Prodromal symptoms were more frequent in athletes than in nonathletes of the same age who died suddenly, 32 vs. 23%, respectively, as observed by Corrado et al. [21]. This suggests that even minor, non-specific health complaints in regularly training athletes must be taken seriously by doctors, coaches, and the athletes themselves, as they may herald the onset of a life-threatening event. Some conditions in athletes, often considered to be undoubtedly life-threatening, such as syncope, to the contrary, are not always associated with a risk of sudden death, although that risk should always be ruled out first. For example, cardiac diseases with a high risk of SCD that required a withdrawal from the sports were revealed only in two (0.4%) of 474 young athletes with syncope [22]; these diseases were hypertrophic cardiomyopathy (HCM) in one case and arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVC) in the other. In our study [23], no diseases possessing a risk of SCD and requiring a withdrawal from sports have been identified in any of the 34 high-level athletes who had a history of syncope.
