RESUMO
BACKGROUND AND OBJECTIVES: To study the frequency of genetic mutations related to genetic heart disease among young patients admitted for syncope during sport practice. PATIENTS AND METHODS: A case series study that included patients≤45 years admitted for syncope during sport practice during 2010-2011. We collected demographic and clinical variables, genetic tests mutations and final clinical diagnosis. RESULTS: A genetic test was performed in 46 (76.7%) of 60 patients evaluated. The genetic test was positive in 12 (26%; 95% CI 15.6-40.3) patients; 10 (21.7%) had PKP2 mutation related to arrhythmogenic right ventricular dysplasia mutation, one (2.2%) KCNQ1 mutation and one (2.2%) SCN5A mutation related to channelopathies. The genetic test was positive in 11 (35.5%) cases of undetermined syncope and one (50%) case of cardiac syncope, being negative in all cases with neuromediated syncopes (P=.037). CONCLUSIONS: Gene mutations are common in young patients suffering from syncope during sports, especially in those with cardiac or undetermined aetiology.