Acquired long QT interval syndrome as a predictor of sudden cardiac death: Causes, diagnostic criteria, and management strategy

Abstract

Despite medical advances in diagnosis and treatment, cardiovascular disease remains the leading cause of death worldwide. Sudden cardiac death, an extreme and irreversible outcome of cardiac arrest, is observed in 50% of cases and is often the first suddenly detected pathology. Long QT syndrome is a variant of electrical heart disease resulting from both congenital and acquired dysfunction and/or regulation of cardiomyocyte ion channels, accompanied by impaired depolarization and repolarization of the ventricular myocardium and characterized by QT prolongation and T abnormalities on the electrocardiogram, clinically accompanied by syncope, bidirectional spindle ventricular tachycardia of the “pirouette” type (torsade de pointes), associated with a high risk of sudden cardiac death or sudden arrhythmic death syndrome. Effective management of these patients requires an individualized approach: careful examination, calculation of corrected QT, determination of typology (hereditary or acquired syndrome), risk assessment using the Tisdale scale, and selection of optimal therapy. Treatment should be comprehensive and include pharmacological (beta-adrenergic blockers, correction of electrolyte balance) and surgical (implantable cardioverter-defibrillator and left-sided thoracic sympathetic denervation of the heart), lifestyle (avoidance of drugs that contribute to prolongation of the QT interval, avoidance of specific arrhythmia triggers (active swimming, exposure to loud noises)) and regular consultation with a cardiologist. Early diagnosis and a comprehensive approach are key to successful prevention of sudden cardiac death in patients with Long QT syndrome.