Fluid bypass conduit for left atrial pressure management

1 . A method of reducing left atrial pressure for treating heart failure and improving heart function, the method comprising:

advancing a delivery catheter to a right atrium of a heart of a patient via a transcatheter access path;

advancing the delivery catheter into a coronary sinus;

advancing the delivery catheter through a wall separating the coronary sinus from a left atrium of the heart;

deploying a distal end of a bypass fluid conduit from the delivery catheter;

anchoring the distal end of the bypass fluid conduit to a pulmonary vein, the distal end of the bypass fluid conduit comprising a distal axial inlet that is co-axial with an axis of the bypass fluid conduit;

withdrawing the delivery catheter through the wall separating the coronary sinus from the left atrium, thereby exposing at least a portion of a medial segment of the bypass fluid conduit in the left atrium;

anchoring a proximal end of the bypass fluid conduit to the wall separating the coronary sinus from the left atrium to thereby form a direct shunt flow channel from the pulmonary vein into the coronary sinus; and

withdrawing the delivery catheter from the heart;

wherein the distal axial inlet of the bypass fluid conduit seals the pulmonary vein without gaps between an outer diameter of the bypass fluid conduit and an inner wall of the pulmonary vein in a manner as to force blood flow of the pulmonary vein into the medial segment of the bypass fluid conduit via the distal axial inlet for shunting to the right atrium via the coronary sinus, thereby reducing blood pressure in the left atrium for treating heart failure.

2 . The method of claim 1 , wherein said anchoring the distal end of the bypass fluid conduit to the pulmonary vein comprises embedding one or more barb tissue anchors associated with the distal end of the bypass fluid conduit into biological tissue associated with the pulmonary vein.

3 . The method of claim 1 , wherein the bypass fluid conduit comprises:

a self-expanding memory metal frame dimensioned to extend from the pulmonary vein to the wall separating the coronary sinus from the left atrium; and

an at least partially fluid-tight covering disposed over at least a portion of the self-expanding memory metal frame.

4 . The method of claim 1 , wherein the proximal end of the bypass fluid conduit comprises a wire coil anchor having a diameter that is greater than a diameter of the bypass fluid conduit.

5 . The method of claim 1 , further comprising anchoring the distal end of the bypass fluid conduit to another pulmonary vein using an anchor coupled to the distal end of the bypass fluid conduit by an arm member.

6 . A method of managing left atrial pressure, the method comprising:

advancing a delivery catheter to a right atrium of a heart of a patient via a transcatheter access path;

advancing the delivery catheter into a coronary sinus;

forming an opening in a wall of the coronary sinus;

passing the delivery catheter through the wall of the coronary sinus and into a left atrium of the heart of a patient;

deploying a distal end of a bypass fluid conduit from the delivery catheter, wherein the bypass fluid conduit is an elongate tube formed with a lumen having a substantially constant diameter;

securing the distal end of the bypass fluid conduit to a first left pulmonary vein, such that blood flow exiting the first left pulmonary vein is forced into a tubular distal axial inlet of the bypass fluid conduit that is aligned with an axis of the bypass fluid conduit;

anchoring a proximal end of the bypass fluid conduit to a tissue wall associated with the coronary sinus to thereby form a direct shunt flow channel from the first left pulmonary vein into the coronary sinus to divert 25% of total oxygenated blood flow from lungs of the patient; and

withdrawing the delivery catheter from the heart;

wherein the 25% of the total oxygenated blood is diverted such that no blood from the first left pulmonary vein enters the left atrium, thereby reducing left atrial pressure and alleviating heart failure symptoms and improving heart function.

7 . The method of claim 6 , wherein sealing-off the opening of the first left pulmonary vein includes expanding a self-expanding stent structure associated with the distal end of the bypass fluid conduit within the first left pulmonary vein.

8 . The method of claim 6 , wherein the proximal end of the bypass fluid conduit comprises a wireform coil that is expandable.

9 . The method of claim 6 , wherein the bypass fluid conduit comprises a metal frame having a biocompatible, fluid-tight covering.

10 . The method of claim 6 , wherein sealing-off the opening of the first left pulmonary vein involves embedding barbs associated with the distal end of the bypass fluid conduit in an inner wall of the first left pulmonary vein, the barbs extending distally from the distal end of the bypass fluid conduit and curving around to project in a proximal direction.

11 . The method of claim 6 , wherein the tissue wall is a coronary sinus septum.

12 . The method of claim 6 , wherein the tissue wall separates the left atrium from the coronary sinus.

13 . The method of claim 6 , further comprising:

expanding a first stent in the first left pulmonary vein, the first stent being associated with the distal end of the bypass fluid conduit; and

expanding a second stent in a second left pulmonary vein, the second stent being coupled to the first stent by a bridge member.

14 . The method of claim 6 , further comprising anchoring the distal end of the bypass fluid conduit to a second left pulmonary vein using an anchor coupled to the distal end of the bypass fluid conduit by an arm member.

15 . The method of claim 6 , wherein the bypass fluid conduit has associated therewith an accordion feature configured to axially contract to cause axial contraction of the bypass fluid conduit.

16 . The method of claim 15 , wherein the accordion feature comprises a plurality of pleated layers of a covering of the bypass fluid conduit.

17 . A method of managing left atrial pressure, the method comprising:

advancing a delivery catheter to a right atrium of a heart of a patient via a transcatheter access path;

advancing the delivery catheter into a coronary sinus;

advancing the delivery catheter through a tissue wall that separates a left atrium of the heart from the coronary sinus;

deploying a distal end of a fluid-tight shunt tube from the delivery catheter, the fluid-tight shunt tube comprising a self-expanding frame and a fabric covering;

anchoring the distal end of the fluid-tight shunt tube to a pulmonary vein, the distal end of the fluid-tight shunt tube comprising a distal axial inlet aligned with an axis of the fluid-tight shunt tube;

withdrawing the delivery catheter through the tissue wall, thereby exposing at least a portion of a medial segment of the fluid-tight shunt tube in the left atrium;

anchoring a plurality of anchor arms emanating from a proximal end of the fluid-tight shunt tube within the coronary sinus, thereby providing fluid access from the pulmonary vein into the coronary sinus from the fluid-tight shunt tube; and

withdrawing the delivery catheter from the heart;

wherein the distal axial inlet of the fluid-tight shunt tube is sized such that an outer diameter thereof contacts an inner wall of the pulmonary vein around a circumference of the fluid-tight shunt tube to seal the pulmonary vein in a manner as to force blood flow of the pulmonary vein into the medial segment of the fluid-tight shunt tube via the distal axial inlet for shunting to a right side of the heart via the coronary sinus to reduce left atrial pressure.

18 . The method of claim 17 , wherein withdrawing the delivery catheter through the tissue wall involves withdrawing the delivery catheter through the coronary sinus.