In at least one embodiment, a catheter for insertion into a patient for providing treatment is provided. The catheter comprises an elongated shaft having a proximal portion extending to a distal portion. The proximal portion has a plurality of first lumens formed therethrough and at least one septum separating the first lumens in non-coaxial relationship with each other. The first lumens each have an associated flow area for providing the treatment through the proximal portion. The distal portion has a second lumen in fluid communication with the first lumens. The septum terminates distally in the proximal portion to merge the first lumens with the second lumen. The second lumen has a second flow area that is greater than any one of the associated flow areas of the first lumens for providing the treatment to the patient.
