Table 2. Collaterals and the effect on circulation.

Type	Shunt	Effect on circulation
Systemic venous > systemic venous	No	Decreased flow via Glenn
Systemic venous > pulmonary venous	Deoxy > Oxy	Increased preload SV; (high output state); systemic desaturation
	Oxy > Deoxy	Increased preload SPV
Systemic arterial > systemic venous	Oxy > Deoxy	Increased preload SV and SPV
Pulmonary arterial > pulmonary venous	Deoxy > Oxy	Increased preload SV; high output state; systemic desaturation
Systemic arterial > pulmonary arterial	Oxy > Deoxy	Increased afterload SPV

Deoxy, deoxygenated; Oxy, oxygenated; SV, system ventricle; SPV, subpulmonary ventricle.