Closed tip dynamic microvalve protection device

A device for temporary use during infusion of an infusate in a blood vessel in an intravascular procedure, comprising:

• a) a flexible outer catheter comprising a proximal end and a distal end, the flexible outer catheter extending along a longitudinal axis from the proximal end to the distal end;
• b) an inner catheter comprising a proximal end and a distal end, and defining therein an infusion lumen extending between the proximal and distal ends of the inner catheter and opening to an orifice at the distal end of the inner catheter, the inner catheter extending through and longitudinally displaceable relative to the outer catheter, and an annular space defined between the inner and outer catheters;
• c) a filter valve comprising a proximal end, a distal end, and a non-porous filter portion adapted to capture the infusate, the proximal end of the filter valve coupled to the outer catheter adjacent to the distal end of the outer catheter, and the distal end of the filter valve coupled to the inner catheter adjacent to the distal end of the inner catheter, such that longitudinal displacement of the inner catheter relative to the outer catheter moves the filter valve from a non-deployed configuration to a deployed configuration,
• wherein the distal end of the inner catheter of the device in the non-deployed configuration is distally advanced by a first distance relative to the distal end of the outer catheter such that the filter valve has a non-deployed diameter configured for advancement through the vessel;
• d) a first port in fluid communication with the infusion lumen;
• e) a second port extending at an angle to the longitudinal axis of the flexible outer catheter and being in fluid communication with the annular space;
• and
• f) a first radio-opaque marker band located at the distal end of the inner catheter, a second radio-opaque marker band located at the distal end of the flexible outer catheter, and a third radio-opaque marker band located on the inner catheter at a fixed distance proximal of the first radio-opaque marker band and at an adjustable longitudinal distance from the second radio-opaque marker band,
• wherein the adjustable longitudinal distance between the second and third radio-opaque marker bands decreases as the filter valve moves from the non-deployed configuration to the deployed configuration.