QT luzearen sindromea kanalopatia larria da. 2.500 pertsonatik bati eragiten dio, bereziki gazteei. Bihotzeko bentrikuluen zelulen birpolarizazio-fasearen luzatzea du ezaugarri eta, ondorioz, elektrokardiograman QT tartearen luzapena ageri da. Horrek gaixoei sinkopea eta fibrilazio bentrikularrak eragindako bat-bateko heriotza izateko arriskua handitzen die. Sindrome hau kirolarien bat-bateko heriotzaren arrazoietako bat da. Gaixo sintomatikoen edo elektrokardiograma patologikoa dutenen maneiua aski ezaguna da, baina azken urteotan gaixotasun hau eragiten duten hainbat mutazio genetiko deskribatu dira, oraindik adierazpen fenotipikorik ez duten zenbait pertsonatan. Gero eta hedatuago dagoen proba genetikoen erabilerak mutazio mota horien eramaile asko diagnostikatzea erraztu du. Gako-hitzak: bat-bateko heriotza, bihotza, sindromea, sinkopea, torsades de pointes, QT luzea Long QT syndrome is a channelopathy that affects approximately one in 2,500 people, mainly young people. It is characterized by a prolongation of ventricular repolarization that is manifested by an increase in the QT interval on the electrocardiogram. This exposes patients to syncope and sudden death from ventricular fibrillation. This syndrome is one of the possible causes of sudden death in sports. The management of symptomatic patients or those with electrocardiographic expression is known. However, in recent years, genetic mutations have been described, predisposing people to suffer from this pathology even without phenotypic manifestation. The increasingly widespread application of genetic testing has allowed discovering many carriers of this type of mutations. Keywords: sudden death, heart, syndrome, syncope, torsades de pointes, long QT