Rapid ventricular tachycardia in patients with tetralogy of Fallot and implantable cardioverter-defibrillator: Insights from the DAI-T4F nationwide registry

Evaluation and Management of Sudden Death Risk in Repaired Tetralogy of Fallot

Although substantial progress has been made to prevent sudden cardiac death in repaired tetralogy of Fallot patients, ventricular arrhythmia and sudden death continue to be major causes of morbidity and mortality in these patients. Greater survival in contemporary cohorts has been attributed to enhanced surgical techniques, more effective management of heart failure, and increased efforts in risk stratification and management of ventricular arrhythmias. More recently, our understanding of predictive risk factors has evolved into personalized risk prediction tools that rely on comprehensive demographic, imaging, functional, and electrophysiological data. However, the universal applicability of these different scoring systems is limited due to differences between study cohorts, types of anatomic repair, imaging modalities, and disease complexity. Noninvasive risk stratification is critical to identify those who may derive benefit from catheter ablation or cardioverter defibrillator implantation for primary prevention. Ultimately, assessment and risk stratification by a multidisciplinary team is crucial to analyze the various complex factors for every individual patient and discuss further options with patients and their families.

Risk Stratification for Sudden Cardiac Death in Repaired Tetralogy of Fallot

There has been significant progress in the prevention of sudden cardiac death in repaired tetralogy of Fallot. Contemporary cohorts report greater survival attributable to improved surgical techniques, heart failure management, and proactive strategies for risk stratification and management of ventricular arrhythmias including defibrillator implantation and ablation technology. Over the last 25 years, our understanding of predictive risk factors has also improved from invasive and more limited measures to individualized risk prediction scores based on extensive demographic, imaging, electrophysiological, and functional data. Although each of these contemporary scoring systems improves prediction, there are important differences between the study cohorts, included risk factors, and imaging modalities that can significantly affect interpretation and implementation for the individual patient. In addition, accurate phenotyping of disease complexity and anatomic repair substantially modulates this risk and the mechanism of sudden death. Routine implementation of risk stratification within repaired tetralogy of Fallot management is important and directly informs primary prevention defibrillator implantation as well as consideration for proactive invasive strategies including ventricular tachycardia ablation and pulmonary valve replacement. Assessment and risk stratification by a multidisciplinary team of experts in adult congenital heart disease are crucial and critical. Although we have increased understanding, reconciliation of these complex factors for the individual patient remains challenging and often requires careful consideration and discussion with multidisciplinary teams, patients, and their families.

Prediction of Sudden Death Risk in Patients with Congenital Heart Diseases

Risk stratification for sudden death should be discussed with patients with congenital heart disease at each stage of personal and cardiac development. For most patients, risk is low through teenage years and the critical factors to consider are anatomy, ventricular function, and symptoms. By adulthood, these are supplemented by screening for atrial arrhythmias, ventricular arrhythmias, and pulmonary hypertension. Therapies include medication, ablation, and defibrillator placement.