Platonov PG, et al. - Researchers examined the risk of atrial fibrillation (AF) in patients with long QT syndrome (LQTS) and assessed how this risk is related to the LQTS genotype and the long-term prognosis of these patients. Comparison of genotype-positive patients with LQTS (784 LQT1, 746 LQT2, and 233 LQT3) with 2,043 genotype-negative family members was done. Among patients who were followed from birth to 60 years of age, an increased risk of AF was observed for patients with LQT3 compared with genotype-negative family members, while their was no increased AF risk with either LQT1 or LQT2. After the age of 60 years, they noted significantly lower risk of AF among patients with LQT2 vs genotype-negative controls. In patients with LQT3 through the age of 60, they identified AF as a significant predictor of cardiac events.