Q—T 间期延长综合征是少见的一种心脏疾患,常致猝死。如在无晕厥发作前临床上可无特殊表现,实际工作中稍不警惕容易误诊。现将我科1986年2—6月收治二例及其家系调查,结合文献复习报告于后:例一:男,11岁,住院号77010,因家庭中近6—7年其母、兄、姐先后原因不明突然死亡而要求检查。体检:发育营养一般,听力正常,除常规心电图描记 Q—T 间期延长0.44″以外均无特殊发现。既往史:健康 Q-T prolongation syndrome is a rare heart disease, often caused by sudden death. If there is no clinical manifestations before the onset of syncope can be no special performance, the actual work is not easy to be misdiagnosed. Now our department from 1986 to June 1986 admitted two cases and their pedigree investigation, combined with literature review report later: Example 1: male, 11 years old, hospital number 77010, because the family in the past 6-7 years of their mother, brother, Sister unexplained sudden death and asked to check. Physical examination: normal developmental nutrition, normal hearing, except for conventional electrocardiography Q-T interval 0.44 "beyond the extension were no special findings. Past history: health