| Abstract [eng] |
Congenital long QT syndrome is a genetic dysfunction of ion channels in cardiomyocytes, leading to abnormal repolarization and prolonged action potential duration. The syndrome is associated with increased risk of life-threatening ventricular arrythmias, such as Torsades de pointes, and sudden cardiac death. The disease manifests with syncope episodes during exercise or at rest, dizziness, palpitations. In some cases, sudden cardiac death can be the first and only manifestation of the disease in an asymptomatic young individual with no apparent structural heart abnormalities. Congenital long QT syndrome is one of the leading causes of sudden cardiac death at a young age. Diagnosis is established based on detailed patient and family history, 12-lead electrocardiogram, Holter monitoring, exercise stress testing, and, if necessary, imaging studies to rule out other cardiac conditions. Genetic testing is important in all patients with suspected congenital long QT syndrome. The main syndrome types: first, second and third, account for approximately 90% of all genetically confirmed cases. Pregnancy and postpartum period are considered high-risk, due to significant cardiovascular system changes, therefore, multidisciplinary specialist care is crucial during these stages to minimize the risk of cardiac events for both the mother and the fetus. While the risk of life-threatening arrythmias decreases during pregnancy, it significantly increases in the first nine months postpartum, particularly in patients with long QT syndrome type 2. A significant portion of antiarrhythmic drugs crosses the placental barrier, but due to lack of clinical studies involving pregnant women, the exact safety and efficacy of the drug remain unknown. The key aspect of medication use during pregnancy include assessing the benefits for the mother and potential harm to the fetus. Beta-adrenergic blockers are the cornerstone treatment for pregnant patients with long QT syndrome. First-line medications include non-selective beta-blockers such as nadolol or propranolol. When indicated, an implantable cardioverter–defibrillator is recommended prior to pregnancy, however, in high-risk patients, implantation may also be considered during pregnancy. Left cardiac sympathetic denervation can be an option for symptomatic patients, if other treatments are ineffective, however, it is recommended to postpone this procedure until after delivery. Pregnant women, who are at moderate to high risk, should give birth in a specialized tertiary care center. A multidisciplinary team of specialists should develop a comprehensive delivery plan, which includes preparation for intravenous beta-blocker administration, and, in cases of hemodynamic instability – electrical cardioversion or external defibrillation. |
