Atrial Tachyarrhythmias with Ultra-Rapid Ventricular Response and Sudden Death in Patients Without Structural Heart Disease (JCEP March 2025)-Article: Atrial Tachyarrhythmias with Ultra-Rapid Ventricular Response and Sudden Death in Patients Without Structural Heart Disease

Article: Atrial Tachyarrhythmias with Ultra-Rapid Ventricular Response and Sudden Death in Patients Without Structural Heart Disease

Back to course

Pdf Summary

This study investigates sudden cardiac death (SCD) among patients without structural heart disease, emphasizing the potential role of atrial tachyarrhythmias (ATAs) with ultra-rapid ventricular response as a cause of SCD previously attributed to ventricular fibrillation (VF) or ventricular tachycardia (VT). The research highlights a case series of 5 young, resuscitated SCD survivors, who exhibited syncope treated with implantable cardioverter-defibrillator (ICD) shocks, in settings of high adrenergic tone, such as during physical exertion. <br /><br />In these patients, initially presumed to suffer from idiopathic VF, ICD interrogation revealed that ATA, particularly atrial fibrillation (AF) or atrial tachycardia (AT), caused the ultra-rapid ventricular rates. This high ventricular response rate, nearing 1:1 atrioventricular (AV) conduction, was similar to malignant VF, causing hemodynamic instability and syncope. In all cases after ATA ablation, prolonged follow-up (median 34 months) showed the absence of recurrence of arrhythmia, syncope, or ICD shock therapy, underscoring the ATA’s role in SCD and suggesting that catheter ablation is an effective treatment.<br /><br />The findings argue that, in young patients who have experienced syncope and are believed to have SCD due to ventricular arrhythmias, ATA should also be considered as a potential cause. Supraventricular arrhythmias like AF or AT can trigger SCD by evoking rapid ventricular response leading to hemodynamic collapse, similar to VF. This mandates early intervention via ablation, challenging the traditional treatment focus on ICD implantation alone. It underlines the necessity of re-evaluating SCD cases predominantly through ICD records and interpretative lenses, highlighting the need for a broader diagnostic approach for preventative measures in at-risk individuals.

Keywords

sudden cardiac death

atrial tachyarrhythmias

ultra-rapid ventricular response

ventricular fibrillation

ventricular tachycardia

implantable cardioverter-defibrillator

atrial fibrillation

atrial tachycardia

catheter ablation

hemodynamic instability