A guide catheter includes a hollow elongate shaft defining a channel. The hollow elongate shaft (or a segment thereof) includes an inner tube and a multilayer sheath formed around the inner tube. The multilayer sheath includes an intermediate layer derived from a melt-processible first polyether-block amide material (e.g., PEBAX.RTM.) and an outer layer derived from a different second polyether-block amide (e.g. a cross-linked polyether-block amide material). Reinforcing material (such as a braid of reinforcing filament) may be part of the multilayer sheath. The second polyether-block amide layer of the outer layer provides a shrink tube with a shrink temperature range greater than melt temperature range of the first polyether-block amide material of the intermediate layer. The hollow elongate shaft is formed by heating the intermediate and outer layers at a temperature within the shrink temperature range such that the outer shrink tube layer shrinks and the intermediate layer melts to thereby bond the multilayer sheath to the inner tube.