A medical catheter having an elongate body, a first expandable balloon and
a filter assembly. The filter assembly includes an expandable filter
having a first portion coupled to a portion of the medical catheter and a
second portion positioned around at least a portion of the first
expandable balloon to form a channel between the filter assembly and the
first expandable balloon. The filter assembly can further include struts
coupled to the second portion of the expandable filter, where the struts
tether the second portion of the expandable filter to the elongate body
adjacent the proximal end of the first expandable balloon. The first
expandable balloon can be used in procedures to dilate blood vessels,
including those that deploy stents, where the expandable filter assembly
captures particles, including embolic particles, from the blood during
the procedure.