Sustained Ventricular Tachycardia in a Patient with Tetralogy of Fallot—with a “Twist”

Abstract

KEY POINTS There are common and uncommon associated conditions that may accompany patients with tetralogy of Fallot (TOF). These associated conditions may significantly complicate surgical or percutaneous treatment of patients with TOF. Arrhythmias are often the result of hemodynamic compromise in TOF. Most commonly this is due to progressive right ventricular dilatation secondary to chronic pulmonary valve regurgitation. Evaluation of arrhythmias should always be preceded by an evaluation of the patient’s surgical repair (valves, conduits, ventricular septal defect) and hemodynamics. Surgical pulmonary valve replacement has been demonstrated to reduce the risk of ventricular tachycardia in patients with severe pulmonary regurgitation and RV enlargement. Among patients who present with ventricular tachycardia in the absence of a correctable lesion or hemodynamic compromise, an electrophysiologic study and radiofrequency ablation may be an effective option for the treatment of ventricular tachycardia. Although clinical risk factors associated with ventricular arrhythmias and sudden death have been identified, appropriate selection of patients who would benefit from an implantable cardioverterdefibrillator (ICD) for primary or even secondary prevention of sudden death remains a clinical challenge. Preliminary data have demonstrated that appropriate ICD shocks occur frequently among patients who have an ICD implanted, but inappropriate shocks and immediate and long-term complications are frequent in the population, and should be weighed carefully when considering ICD implantation. Current guidelines for ICD implantation endorse implantation of an ICD for secondary prevention, or among patients who experience syncope that is concerning for cardiac arrhythmia and inducible sustained monomorphic ventricular tachycardia at electrophysiologic study.