[II-JCKAP1-5] Analysis of Types and Prognosis of Incidentally Discovered Long QT Syndrome: Insights from a Korean Multicenter Cohort
キーワード：Long QT syndrome, findings, incidental , death, sudden
Long QT Syndrome (LQTS) is often incidentally discovered during routine electrocardiogram screenings, posing challenges in management and prognosis. This multicenter study in Korea focused on Long QT Syndrome (LQTS) incidentally discovered during routine screenings. Of 223 patients with LQTS, 86 were asymptomatic at diagnosis. Genetic tests revealed 68 asymptomatic patients (79.1%) carried variants of uncertain significance (VUS), with KCNQ1 mutations being the most prevalent (60.3%), followed by KCNH2 (14.7%) and SCN5A (11.8%). The frequency of KCNQ1 mutations was notably higher in asymptomatic (47.7%) compared to symptomatic patients (30.7%, p=0.002). The mean QTc interval at diagnosis for asymptomatic individuals was 508 ms. Of these, 64 patients (74.4%) had no underlying disease, while 59 (68.6%) reported a family history of cardiac conditions. Medication impacted QTc intervals significantly, with medicated patients averaging 451.94 ms and non-medicated patients 416.79 ms (p=0.015). The 5-year event-free survival rate was high at 92.3%, with medicated patients showing a survival rate of 96.2% versus 81.7% for those without medication (p=0.002). These findings highlight the critical role of genetic profiling and medication in managing asymptomatic LQTS, improving prognosis and survival outcomes. The study provides important insights into the implications of incidental LQTS findings and stresses the need for thorough genetic analysis and careful clinical management in these patients.