A catheter includes an elongated tubular body including a first wall and second wall defining first and second lumens, respectively. Each wall extends to a distal end and defines a distal opening. The first and second walls may each include one or more side openings disposed proximal of the distal end. The first and second lumens are separated by a septum. The septum includes a septum extension extending distally from the septum. The septum extension is adapted to articulate relative to the septum in response to fluid flow into and out of the distal openings of the first and second lumens. The septum extension is dimensioned to partially obstruct fluid flow into the catheter through one of the distal openings upon the articulation of the septum extension.
