A catheter assembly comprises a catheter shaft having a first region and a second
region. The first region is less radiopaque than the second region. The first region
is constructed of a shaft material and the second region is constructed from the
shaft material in combination with at least one radiopaque material. At least a
portion of the shaft material of the second region defines at least one grooved
region. The at least one radiopaque material is positioned at least partially within
the at least one grooved region.