Ventricular arrhythmia in congenital heart diseases with a systemic right ventricle

Congenital heart disease (CHD) often involves the systemic right ventricle (SRV), which is the morphological right ventricle that supports systemic circulation. SRV patients are at a higher risk of sudden cardiac death (SCD) than other adult CHD patients and continues to be a significant cause of death in this aging population. However, the pathophysiology of ventricular arrhythmias in SRV is still not fully understood, and there may be differences between subtypes of CHD. Although these events are rare, predicting them is challenging. This review discusses contemporary strategies for assessing and preventing the risk of ventricular arrhythmias in SRV patients. Several risk factors have been identified to be associated with ventricular arrhythmias in patients with SRV. A recent risk stratification model combines independently associated factors into a risk score, and subpulmonary left ventricle dysfunction is emerging as a critical factor in risk assessment. Cardiac magnetic resonance imaging, biomarkers, and genetic data may refine the ability to predict ventricular arrhythmias in SRV. However, the question of whether implantable cardioverter-defibrillators (ICDs) should be used as a preventive measure in this cohort remains unanswered. Multicenter studies are needed to evaluate risk models and ICD use in this aging population. Given that ICDs have drawbacks, such as a high rate of inappropriate shocks and late lead-related complications, shared clinical decision-making is crucial when considering their use. The review emphasizes the need for further research in this area to improve the identification of patients at risk of clinical ventricular arrhythmias and to develop effective prevention strategies.