Vasovagal syncope with mild versus moderate autonomic dysfunction: a 13-year single-center experience

BACKGROUND: An adequate large-scale pediatric cohort based on nationwide administrative data is lacking in Korea. PURPOSE: This study aimed to differentiate patients with VVS by autonomic dysfunction severity using the composite autonomic severity score (CASS) and compare the clinical manifestations and prognosis between patient subgroups. METHODS: We retrospectively reviewed the medical records of 66 VVS patients divided into 3 groups by CASS. To compare the differences between these groups, we analyzed VVS type, triggers, prodromal symptoms, management of syncope, and prognosis between patients with mild versus moderate autonomic dysfunction. RESULTS: Of our 66 patients with VVS, 41 had mild autonomic dysfunction (62.1%) and 25 had moderate autonomic dysfunction (37.9%). We found no significant intergroup differences in age, sex, inducible factor (P=0.172), prodromal symptoms, laboratory findings, head-up tilt test, type of syncope, or prognosis (P=0.154). CONCLUSION: We found no evidence that autonomic dysfunction degree is affected by VVS characteristics, test findings, parameters, or prognosis; therefore, no further evaluations are needed to classify autonomic dysfunction severity.