The outer layer of the hypotube is processed to remove material. Through this process, the high-precision outer diameter and thinner wall of the hypotube can be achieved to meet some complex catheter designs such as suction.

In the design concept of interventional catheters, metal hypotube laser cutting with excellent performance are increasingly used in valve delivery, microcatheters, and other types of consumables.

As a metal material with excellent performance, hypotube can provide properties including bending, pushing, and torque. However, how to balance these properties, such as flexibility in bending resistance and weakening of pushing force, is the key to catheter design.

We can start with the key features of hypotubes and how these impact the physician’s experience when placing the catheter in a patient.

Torque

Luminal systems such as blood vessels are often tortuous or highly calcified. Importantly, doctors can rotate the catheter within the luminal system to reach the target treatment site. The torque capability of a catheter can be judged by measuring the effect of accurate transmission along its length. When torque force is not accurately transmitted, it may cause force superposition and produce undesirable effects along the axis. A good hypotube design ensures that it provides the necessary torque along the axis and provides predictable movement during rotation.

Push

Push is generally determined by measuring the transfer of longitudinal force from the proximal end to the distal end of the catheter. Ideally, when the physician applies thrust, the distal tip within the patient should exhibit the same force motion, and physicians will generally be able to navigate with confidence when transmitted forces are higher. Good pushing force performance is another focus of catheter design.

Traceable

It is used to measure the overall ability of the catheter to pass through the complex lumen system and reach the treatment site. On the doctor's side, it can be understood as the overall feeling of the catheter or its response to surgical operations. Among them, the distal or treatment end of the catheter plays a crucial role in overall traceability. Advanced hypotube processing technology can make the distal end of the catheter more flexible, thus aiding traceability.

Toughness

Toughness, a measure of stiffness along the length of the wave tube, is a key part of the overall conduit design and a major factor in trackability or feel. Although general catheters require large pushability or stiffness, good hypotube design needs to match the angle of advancement or anatomical structure.

Anti-kink

Advancing a catheter within a blood vessel can be challenging, especially when the surgeon is required to navigate a sharp radius. Kink resistance is a measure of the hypotube's ability to maintain full arc through the bend radius, a characteristic that is critical to maintaining a clear lumen. Generally, 304V and other materials that are better than ordinary 304L are used.

Other properties, such as lubrication, also have a certain impact on hypotube design.

Some design examples

• 1. Balloon field: Creating a burr-free cutting edge in some thin-walled hypotubes allows it to form a smooth transition area between the metal shaft and the distal balloon component, thus improving the overall trackability and flexibility of the catheter.
• 2. Delivery system: Hypocutting offers a variety of cutting geometries that help improve flexibility, torque and compression, especially on some high-load conduit applications.
• 3. Complex conduit: The outer layer of the hypotube and  is processed to remove Ultra-Fine Nitinol material. Through this process, the high-precision outer diameter and thinner wall of the hypotube can be achieved to meet some complex conduit designs such as suction.