Catheters and Related Devices for Forming Passageways Between Blood Vessels or Other Anatomical Structures

A catheter device, comprising:

• an elongate flexible catheter having a distal portion insertable into a blood vessel of a human subject;
• a tissue penetrating member configured to extend in a first direction from the distal portion of the catheter;
• a balloon which, when inflated, extends from the distal portion of the catheter in a second direction opposite the first direction;
• and
• a lumen extending through the catheter and useable for inflation and deflation of the balloon.

A method for treating a human patient, the method comprising:

• positioning a distal portion of an elongate flexible catheter within a blood vessel of the patient, wherein the catheter includes—
• a tissue penetrating member configured to extend in a first direction from the distal portion of the catheter toward a perivascular target location outside of the blood vessel;
• and
• an inflatable pressure exerting member transformable between a low-profile delivery state and an inflated state,
• wherein, in the inflated state, the pressure exerting member extends from the distal portion of the catheter in a second direction opposite the first direction;
• inflating the pressure exerting member via inflation fluid passed through a lumen of the catheter;
• and
• advancing the tissue penetrating member toward the perivascular target location simultaneous with inflation of the pressure exerting member.