Understanding Venoarterial (VA) and Venovenous (VV) ECMO

Types of ECMO

Types of ECMO

There are two types of ECMO. Venoarterial (VA) ECMO can be used for heart and lung support, while venovenous (VV) ECMO is used for lung support only. The ECMO team will decide which type will help your loved one the most, based on his or her specific illness.

Venoarterial (VA) ECMO

Venoarterial (VA) ECMO provides support for the patient's heart and lungs by allowing most of a patient's blood to move through the circuit without going through the patient's heart. This type of ECMO takes blood out of a large vein and returns it into a large artery, allowing oxygen-rich blood to circulate through the body even if the heart is too weak to pump it. Therefore, two cannulas must be placed in either the neck or the groin(s).

Venovenous (VV) ECMO

Venovenous (VV) ECMO provides lung support only, so the patient's heart must still function well enough to meet the body's needs. Two cannulas are placed into veins in spots close to or inside the heart. With VV ECMO, the surgeon cannulating physician has an option of using a special type of cannula with two lumens (pathways inside the tubing). This allows for blood to leave and return to the body in one place, creating the need for only one entry site instead of two. Blood from the ECMO system returns to the body before the heart, and the patient's own heart pumps the blood throughout the body.

a) VV ECMO using special double-lumen cannula
b) VV ECMO using two regular cannulas