Basket style cardiac mapping catheter having spline bends for detection of cardiac rhythm disorders

A system for sensing multiple local electric voltages from an endocardial surface of a heart, comprising:

• a first elongate tubular member having a lumen, a proximal end and a distal end;
• a basket assembly comprising:
• a plurality of flexible splines guiding a plurality of flexible polymeric strips, the plurality of flexible polymeric strips each having a plurality of electrodes, the splines having proximal portions, distal portions and medial portions therein between;
• a proximal anchor for securably affixing the proximal portions of the splines;
• said proximal anchor being secured at the distal end of the first elongate tubular member;
• a distal tip for securably affixing the distal portions of the splines, said proximal anchor and said distal tip defining a longitudinal axis therein between about which the splines are disposed;
• wherein the basket assembly exhibits a substantially cylindrical shape when radially compressed and exhibits a radially expanded non-spherical shape when not radially compressed;
• wherein at least some of the splines in the radially expanded non-spherical shape contain a distal excurvate outward bend disposed at the distal portion of the spline at a location near to the distal tip of the basket assembly to bend the splines back towards the proximal anchor;
• wherein at least some of the splines in the radially expanded non-spherical shape contain a distal incurvate inward bend between said distal tip and said distal excurvate outward bends;
• wherein, when the basket assembly is in said radially expanded non-spherical shape, the splines extend beyond the distal tip;
• and, when the basket assembly is in said radially expanded non-spherical shape, apices of the distal excurvate bends are disposed beyond the distal tip;
• and
• wherein proximal portions of the flexible polymeric strips are disposed within the proximal anchor;
• wherein the flexible polymeric strips comprise:
• a polymeric substrate having an upper surface and an opposed lower surface with the plurality of electrodes disposed over a portion of the upper surface of the polymeric substrate;
• a plurality of electrical traces disposed over a portion of the lower surface of the polymeric substrate in electrical communication with the plurality of electrodes by way of metal plated holes through the polymeric substrate;
• a first polymeric covering disposed over the plurality of electrical traces and portions of the lower surface of the polymeric substrate not having the plurality of electrical traces thereon;
• wherein the flexible polymeric strips are compressingly and thermally bonded to outer surfaces of second polymeric substrates to define flexible electrode assembly strips with substantially smooth and atraumatic overall outer surfaces.