Histopathology of the right ventricular outflow tract and its relationship to clinical outcomes and arrhythmias in patients with tetralogy of Fallot

The great majority of myocardial tissues in cyanotic tetralogy of Fallot indicates pre-existing ultrastructural hypertrophic and degenerative changes. The changes are more pronounced in older patients subjected to long-standing cyanosis and pressure overload and may account for or may coexist with the higher incidence of myocardial dysfunction and ventricular arrhythmia.