Patent ID: 8177829

Claim:
A balloon catheter comprising: a catheter shaft having an internal catheter lumen; a primary balloon; a side branch shaft having an internal branch lumen; a stent comprising a side branch assembly comprising a first petal and a second petal; the first petal located across the side branch assembly from the second petal, said first petal arranged to unfold at a first location, said second petal arranged to unfold at a second location, a predetermined distance extending between said first location and said second location; and a secondary balloon arranged to unfold said first and second petals, the secondary balloon comprising: an inflatable body portion having an internal volume in fluid communication with the branch lumen, the inflatable body portion comprising a first portion and a second portion, the second portion having a larger cross-sectional area than the first portion, the first portion located closer to the primary balloon than the second portion, a distance across said first portion being less than said predetermined distance, a distance across said second portion being greater than said predetermined distance; wherein the secondary balloon comprises a substantially cylindrical shape at a first inflation pressure, and the second portion assumes a shape having an outwardly extending portion that overhangs the first portion at a second, higher inflation pressure.