An expandable introducer assembly for use in inserting a medical device into a body vessel of a patient includes an expandable sheath subassembly including a sheath hub and an expandable sheath extending from the sheath hub for initial insertion into the body vessel of the patient. The expandable introducer assembly also includes introducer subassembly including a hemostasis valve and an introducer sheath extending from the hemostasis valve and axial advanceable through the sheath hub and into the expandable sheath for radially expanding the body vessel. A coupler is releasably connected to the sheath hub and disposed in interlocked relationship with the hemostasis valve when the hemostasis valve is axially advanced with the introducer sheath towards the sheath hub for allowing serial retraction of the introducer sheath and the expandable sheath out of the body vessel of the patient.
