Catheter shaft with uniform bending stiffness circumferentially

A catheter shaft comprising:

• an inner layer defining an innermost circumferential surface of the catheter shaft and defining a lumen of the catheter shaft, wherein the inner layer is formed of a first polymer;
• and
• an outer layer formed by alternating first and second segments of the first polymer and a second polymer, respectively, that alternate in a circumferential direction, the second polymer being different than the first polymer, each segment of the alternating first and second segments extending in an axial direction for substantially an entire length of the catheter shaft and the alternating first and second segments collectively defining an outermost circumferential surface of the catheter shaft,
• wherein the catheter shaft is devoid of axial wires and has uniform bending stiffness in a circumferential direction.

A catheter shaft comprising:

• an inner layer defining an innermost circumferential surface of the catheter shaft and defining a lumen of the catheter shaft, wherein the inner layer is formed of a first polymer having a first durometer;
• and
• an outer layer formed by alternating first and second segments of the first polymer and a second polymer, respectively, that alternate in a circumferential direction, the second polymer having a second durometer, the second durometer being softer than the first durometer, each segment of the alternating first and second segments extending in an axial direction for substantially an entire length of the catheter shaft and the alternating first and second segments collectively defining an outermost circumferential surface of the catheter shaft,
• wherein the catheter shaft has uniform bending stiffness in a circumferential direction.

A catheter shaft comprising:

• an inner layer defining an innermost circumferential surface of the catheter shaft and defining a lumen of the catheter shaft, wherein the inner layer is formed of a first polymer having a first melting temperature;
• and
• an outer layer formed by alternating first and second segments of the first polymer and a second polymer, respectively, that alternate in a circumferential direction, the second polymer having a second melting temperature, the second melting temperature being lower than the first melting temperature, each segment of the alternating first and second segments extending in an axial direction for substantially an entire length of the catheter shaft and the alternating first and second segments collectively defining an outermost circumferential surface of the catheter shaft,
• wherein the catheter shaft has uniform bending stiffness in a circumferential direction.