An interventional catheter system for treating a blood vessel, comprising: an interventional catheter comprising: an elongate shaft sized for insertion in a blood vessel; a stent positioned on a distal region of the elongate shaft; an expandable dilation member coupled to a distal region of the elongate shaft, the expandable dilation member adapted to expand outward; a stent containment member positioned over the elongate shaft and the stent to contain the stent in a collapsed state; and a control mechanism adapted to retract the stent containment member relative to the elongate shaft; and a transcervical access sheath, characterized in that the transcervical access sheath has a reduced diameter distal region, and in that the interventional catheter system further comprises a flow shunt fluidly connected to the transcervical access sheath and comprising two or more parallel flow lumens (1700, 1705) and a valve to control blood flow to the two or more parallel flow lumens to thereby increase or decrease flow resistance of the flow shunt, and in that the interventional catheter has a working length of approximately 40 cm to 75 cm and is suitable for deployment through the transcervical access sheath when the transcervical access sheath is positioned into the common carotid artery, and when so deployed, the transcervical access sheath and the flow shunt form part of a reverse flow path, wherein the control mechanism is adapted to retract the stent containment member from the elongate shaft to remove the stent containment member from the reduced diameter distal region of the access sheath and from the reverse flow path. an interventional catheter comprising: an elongate shaft sized for insertion in a blood vessel; a stent positioned on a distal region of the elongate shaft; an expandable dilation member coupled to a distal region of the elongate shaft, the expandable dilation member adapted to expand outward; a stent containment member positioned over the elongate shaft and the stent to contain the stent in a collapsed state; and a control mechanism adapted to retract the stent containment member relative to the elongate shaft; and an elongate shaft sized for insertion in a blood vessel; a stent positioned on a distal region of the elongate shaft; an expandable dilation member coupled to a distal region of the elongate shaft, the expandable dilation member adapted to expand outward; a stent containment member positioned over the elongate shaft and the stent to contain the stent in a collapsed state; and a control mechanism adapted to retract the stent containment member relative to the elongate shaft; and a transcervical access sheath, characterized in that the transcervical access sheath has a reduced diameter distal region, and in that the interventional catheter system further comprises a flow shunt fluidly connected to the transcervical access sheath and comprising two or more parallel flow lumens (1700, 1705) and a valve to control blood flow to the two or more parallel flow lumens to thereby increase or decrease flow resistance of the flow shunt, and in that the interventional catheter has a working length of approximately 40 cm to 75 cm and is suitable for deployment through the transcervical access sheath when the transcervical access sheath is positioned into the common carotid artery, and when so deployed, the transcervical access sheath and the flow shunt form part of a reverse flow path, wherein the control mechanism is adapted to retract the stent containment member from the elongate shaft to remove the stent containment member from the reduced diameter distal region of the access sheath and from the reverse flow path.