Method and apparatus for intra-aortic substance delivery to a branch vessel

A renal flow system injects a volume of fluid agent into a location within an abdominal aorta in a manner that flows bi-laterally into each of two renal arteries via their respectively spaced ostia along the abdominal aorta wall. A local injection assembly includes two injection members, each having an injection port that couples to a source of fluid agent externally of the patient. The injection ports may be positioned with an outer region of blood flow along the abdominal aorta wall perfusing the two renal arteries. A flow isolation assembly may isolate flow of the injected agent within the outer region and into the renals. The injection members are delivered to the location in a first radially collapsed condition, and bifurcate across the aorta to inject into the spaced renal ostia. A delivery catheter for upstream interventions is used as a chassis to deliver a bilateral local renal injection assembly to the location within the abdominal aorta.