Multi-lumen intravascular catheters with inner converging lumens for multiple guidewire control

In a multiple-lumen catheter having multiple guidewires for treatment of vascular blockages, each of the multiple lumens being circular in cross-section and having a diameter, the catheter comprising a proximal-end assembly and an elongate tube including a multi-lumen medial portion and a distal-end portion therebeyond, the improvement wherein:

• the multiple guidewires are preloaded in the catheter, each guidewire in its own single-guidewire lumen extending from its own guidewire entry port in the proximal-end assembly through the medial portion of the elongate tube to a lumen convergence portion of the elongate tube;
• the distal-end portion of the elongate tube includes (a) the lumen convergence portion along which the multiple lumens merge into a single output lumen being sized to match the largest-diameter lumen of the multiple lumens, (b) an intermediate distal-end section extending from the lumen convergence portion and surrounding the single output lumen continuing therethrough, and (c) a tapered tip at the end thereof and surrounding the single output lumen continuing therethrough;
• the proximal-end assembly includes (d) one lumen tube for each of the multiple lumens, each tube configured to receive one guidewire, and (e) a transition fixture configured to direct each of the guidewires from its corresponding lumen tube into one lumen of the multi-lumen medial portion, the transition fixture including a guidewire transition guide that has (f) one guide tube for each of the multiple guidewires, each guide tube having a guide lumen with proximal and distal ends, the proximal end of the guide lumen being aligned with its corresponding lumen tube and the distal end of the guide lumen being aligned with its corresponding lumen in the multi-lumen medial portion, and (g) a transition guide web holding all of the guide tubes together;
• and
• each lumen of the multiple lumens other than the single output lumen is sized to match the corresponding guidewire passing therethrough.