Abstract: A catheter device for therapeutic and diagnostic use within a human vascular system has a catheter body with a hub located at a proximal end of the catheter body, and a tip located at a distal end of the body. A guide structure is connected to the catheter body proximate the tip, with the guide structure having a wing shape that provides hemodynamic lift in response to laminar blood flow around the catheter. The wing shape of the guide structure tapers down from a leading edge to a trailing edge, with the leading edge facing the catheter tip so that when the catheter is positioned inside a vessel wall of the vascular system and oriented in a downstream direction, the lift created by the laminar blood flow biases the catheter tip toward the vessel wall. Preferably, the distal end of the catheter body comprises a flexible material so that the catheter tip can deflect laterally towards the vessel wall in response to the hemodynamic lift.

Abstract: A microcatheter with a deployable parachute attached to its distal tip is disclosed. The parachute in its retracted position lies flush against the exterior wall of the distal segment of the catheter. Control strings, cables or wires traverse the length of the microcatheter through channels within its wall and exit through strategically placed apertures at the tip of the microcatheter to attach to the parachute. When the parachute is deployed, the microcatheter is guided by blood flow or jets of liquid that are injected through the microcatheter. When the parachute is retracted, the microcatheter may be used with a guidewire to superselect vasculature. The microcatheter device has multiple uses permitting diagnostic and therapeutic superselective angiography.