Cardiac conduction disorders in young adults: Clinical characteristics and genetic background of an underestimated population

Abstract

BackgroundCardiac conduction disorder (CCD) in patients <50 years old is a rare and mostly unknown condition. ObjectiveWe aimed to assess clinical characteristics and genetic background of patients <50 years old with CCD of unknown origin. MethodsWe retrospectively reviewed a consecutive series of patients with a diagnosis of CCD before the age of 50 years referred to our center between January 2019 and December 2021. Patients underwent complete clinical examination and genetic evaluation. ResultsWe enrolled 39 patients with a median age of 40 years (28–47 years) at the onset of symptoms. A cardiac implantable electronic device was implanted in 69% of the patients. In 15 of 39 CCD index patients (38%), we found a total of 13 different gene variations (3 pathogenic, 6 likely pathogenic, and 4 variants of uncertain significance), mostly in 3 genes (SCN5A, TRPM4, and LMNA). In our cohort, genetic testing led to the decision to implant an implantable cardioverter-defibrillator in 2 patients for the increased risk of sudden cardiac death. ConclusionPatients with the occurrence of CCD before the age of 50 years present with a high rate of pathologic gene variations, mostly in 3 genes (SCN5A, TRPM4, and LMNA). The presence of pathogenic variations may add information about the prognosis and lead to an individualized therapeutic approach.