Structural and Echocardiographic Abnormalities in Congenital Long QT Syndrome: A Review of the Literature

Congenital Long QT Syndrome (LQTS) is a hereditary cardiac channelopathy defined by delayed ventricular repolarization and an elevated risk of life-threatening ventricular arrhythmias. Recent echocardiographic studies using speckle-tracking and strain imaging have identified subtle abnormalities in ventricular and atrial mechanics among LQTS patients, including reduced global longitudinal strain, impaired diastolic function, enlarged left atrial volumes and a consistently negative electromechanical window. These findings challenge the traditional concept of LQTS as solely an electrical disease and support evolving evidence of a subclinical cardiomyopathic phenotype. Left atrial remodeling, although less studied, may represent an underrecognized component of LQTS with potential implications for arrhythmia vulnerability and diastolic dysfunction. This review summarizes current evidence on electromechanical and structural cardiac involvement in congenital LQTS, highlights its diagnostic and clinical implications, and outlines future directions for research in this evolving field.