Table 2: Etiology of heart failure in congenital heart disease.

Primary heart dysfunction
Valvular regurgitation or stenosis
Congenital shunt lesions or systemic pulmonary shunts
Long-standing cyanosis
Arrhythmias
Dysfunction of the subpulmonic ventricle
Inherited abnormalities of the myocardium
Oxygen supply-demand mismatch
The Fontan circulation per se
Associated congenital heart disease in visceral heterotaxy