Medical balloon catheters with enhanced pushability

Abstract

Systems and methods can involve wedge dissectors attached to strips in turn attached to medical balloons, for forming serrations within vascular wall tissue for angioplasty as well as drug delivery.

What is claimed is: 
     
         1 . A medical catheter with enhanced pushability, comprising:
 an outer shaft comprising an elongate member comprising an inner diameter and an outer diameter;   an inner member; and   an elongate coil positioned between the outer shaft and the inner member, the coil extending substantially the entire length of the outer shaft,   wherein the elongate coil comprises one or more tapered portions that tapers from a first larger diameter to a second smaller diameter,   wherein the outer shaft comprises one or more tapered portions that tapers from a first larger diameter to a second smaller diameter, wherein the one or more tapered portions of the elongate coil substantially correlates with the one or more tapered portions of the outer shaft.   
     
     
         2 . The catheter of  claim 1 , wherein the coil comprises at least two tapered portions. 
     
     
         3 . The catheter of  claim 1 , wherein the one or more tapered portions of the coil comprise a pitch of between about 0 degrees and about 15 degrees. 
     
     
         4 . The catheter of  claim 1 , wherein the one or more tapered portions of the coil are all present only between about 5 cm and about 50 cm from a distal tip of the catheter. 
     
     
         5 . The catheter of  claim 1 , wherein the coil is fused to the outer shaft at least at a proximal end of the catheter and/or a distal end of the catheter. 
     
     
         6 . The catheter of  claim 1 , wherein the inner member comprises a guidewire. 
     
     
         7 . The catheter of  claim 1 , further comprising an expandable member associated with the catheter, wherein the elongate coil extends through the expandable member. 
     
     
         8 . The catheter of  claim 7 , wherein the expandable member comprises a balloon. 
     
     
         9 . The catheter of  claim 8 , wherein the expandable balloon comprises a plurality of strips, each strip comprising a plurality of wedge dissectors thereon. 
     
     
         10 . The catheter of  claim 9 , wherein the wedge dissectors are configured to create serrations in a vessel without cutting the vessel. 
     
     
         11 . The catheter of  claim 9 , wherein the wedge dissectors are configured to cut through a portion of a vessel. 
     
     
         12 . A method of creating serrations in a treatment site in a vessel, comprising:
 providing a balloon catheter comprising a balloon comprising a plurality of strips, each strip comprising a plurality of wedge dissectors, the balloon catheter further comprising an inner member, an outer sheath, and an elongate tapered coil between the matched tapered outer sheath and the non-tapered inner member, the elongate coil running substantially the entire length of the balloon catheter and through the balloon;   expanding the balloon at the site to create a plurality of microfissures into the media layer of the vessel wall without cutting the vessel wall; and   removing the balloon from the site.   
     
     
         13 . The method of  claim 12 , further comprising performing an index procedure at the site. 
     
     
         14 . The method of  claim 13 , wherein the index procedure is selected from the group consisting of: endovascular aortic repair (EVAR), fenestrated endovascular aortic repair (FEVAR), transcatheter aortic valve replacement (TAVR), transcatheter mitral valve repair or replacement, and thoracic endovascular aortic repair (TEVAR).