| 主权项 |
1. A method of advancing a catheter into a blood vessel of a patient comprising:
providing a catheter, the catheter comprising an elongate shaft having proximal and distal ends, a length extending between the proximal and distal ends, a distal tip having a lengthwise axis and defining the distal end of the shaft, a distal opening defined by the distal end of the shaft, and a lumen extending proximally from the distal opening through the proximal end of the shaft, wherein an entirety of the distal end of the shaft is oriented at an angle other than 90 degrees to the lengthwise axis of the distal tip, and wherein the shaft has a bend from the distal tip to a location that is at least 10 percent of the shaft length proximal from the distal tip, wherein the bend of the shaft has a maximum concavity of 0.2 cm to 2 cm as measured over a length of 10 cm; advancing a guidewire into a blood vessel of a subject, wherein the guidewire has a bend having a maximum convex curvature, wherein said advancing a guidewire into a blood vessel comprises traversing an obstruction in the blood vessel with the guidewire such that the bend of the guidewire traverses the obstruction and a pap is created between the bend of the guidewire and the obstruction; backloading the guidewire through the distal opening and into the lumen of the shaft; advancing the catheter over the guidewire and into the blood vessel, wherein said advancing the catheter over the guidewire comprises traversing the obstruction with the distal tip of the shaft, after said traversing the obstruction with the guidewire; and self-orienting the shaft on the guidewire as the catheter is advanced over the guidewire such that the maximum concavity of the shaft is aligned with the maximum convex curvature of the guidewire. |
