Balloon Catheter Design and Manufacturing

The balloon catheter is used to deliver stents, open blockages, and dilate vessels as part of minimally invasive procedures. These include delivering stents, opening blockages, and dilating vessels. Non invasive medical devices of high precision requires extensive production know how. In this article, we discuss the design considerations and provide a brief overview of the balloon catheter manufacturing process.

Balloon Catheter Application Considerations

3 Main Balloon Catheter Types

Depending on the use case, the guidance method the physician uses, there are three main types of balloon catheters that can be used:

• Over The Wire (OTW)
• Rapid Exchange (RX)
• Fixed Wire (FW)

Applications

Today high-pressure balloons can have thinner walls, higher strength,  smaller profiles and can be utilized in a wide range of minimally invasive procedures. They can be produced in a wide range of diameters, lengths, and shapes. 

Balloon design and technology enhancements provide increased flexibility for device designers who are involved in developing a new and improved device. As a result, high-pressure balloons are used in a variety of diagnostic and therapeutic procedures: 

• Cardiology, multi-point instead of just single point ablation
• Urology, the combination of temperature sensors provide the ability to test for Piezoelectricity
• ENT, the opening of sinuses can be done using a balloon integrated catheter
• Neurology and Gynecology have specialized balloon catheter uses today, such as combining examination with slow-release drugs delivered through a balloon catheter using a tilting motion

The 3 Foundational Specs

There three key performance characteristics that highly influence balloon catheter design are:

1 – Balloon Inflate/ Deflate time

The time required to inflate and deflate the balloon should as minimal as possible.

In order to achieve this, catheter manufacturers try to design the balloon in a way that maximizes the inner area of the inflation balloon. 

2- Traceability

The second key characteristic is the catheter’s tracking ability to advance through the desired path and reach the treatment area. This is important for complex anatomy, eg. in neurological balloon catheter applications. 

3 – Insertion Profile

Lastly, the insertion profile is another critical balloon catheter characteristic. It denotes the size of the incision required to insert the catheter into the patient. Smaller insertion profiles are of course preferable, since they facilitate quicker patient recovery and easier healing process.

Balloon Catheter Manufacturing Process

Balloon catheters occupy the volume of the natural geometric shape of a physiological region or cavity. This makes them by far the least invasive and most patient friendly operating and treatment method. Moreover, balloon catheters provide an ideal platform for deploying flexible circuit combinations, thereby enabling the development of new and innovative operation methods.

Balloon Catheter Performance

In practical use, balloon catheters must meet certain performance standards to serve as effective medical devices. Factors including inflation and deflation time, trackability, insertion profile, and rated burst pressure determine which applications any given balloon catheter is suitable for.

Inflation and Deflation Time

Inflation and deflation time should be as low as possible, reducing the time it takes to carry out procedures. In most cases, inflation and deflation time are optimized by adjusting the cross-sectional area of the balloon’s inflation lumen, although increased size can lead to tradeoffs with other key performance metrics.

Trackability

An effective balloon catheter must also demonstrate superior trackability. Trackability is the ability of the catheter to advance smoothly and safely through anatomy. Size, shaft design, and tip design all play an important role in catheter trackability. Improving the ability of the catheter to navigate tight and winding anatomy allows for more advanced applications.

Insertion Profile

Along with trackability, the potential applications of a balloon catheter are also determined by its insertion profile. The insertion profile is the size and shape of the opening required for the insertion of the catheter. In surgical applications, a reduced insertion profile means a minimal incision with lower risks of complication. Balloon catheter designs employ a range of tip, shaft, and balloon designs to optimize insertion profile performance.

Rated Burst Pressure

Once inserted into the appropriate location, balloon catheters are inflated and must bear some certain pressure. Every balloon catheter will have a rated burst pressure, which is defined as the maximum pressure at which 99.9% of catheters with that design will survive. Failure of a balloon catheter in use can lead to serious complications, so the design and materials used are carefully selected to meet rated burst pressure performance requirements.

Balloon catheters must be carefully selected for any given application based on these performance requirements. Improvement in one performance metric often means compromising another, so no balloon catheter is perfect for every application. Careful selection and innovative design allow balloon catheters to deliver consistent performance.

Specialized Materials & Manufacturing Techniques 

The materials and manufacturing techniques used in balloon catheter production are:

• Application of hydrophilic materials that offer lubricity, so that friction during catheter insertion is reduced
• Use of radiopaque materials in certain catheter segments, for improved catheter visibility during usage
• Utilization of materials with varying hardnesses, for accurate catheter flexibility control
• Specialized metal braiding techniques and patterns, to offer the physician precise catheter torque manipulation
• Specialized balloon forming techniques to achieve a desired shape or burst pressure levels to ensure safe and efficient balloon operation

Micro Assembly

Balloon catheters have detailed moving parts with specialized functionality. Depending on the assembly needs of the device, catheter manufacturers may need to operate micro-assembly lines. Utilizing a variety of visual aids including microscopes, highly trained and skilled operators perform detailed parts assembly. The result is consistent and reliable fabrication of detailed parts.

Embedded Electronics

An array of electronics may be used to augment balloon catheters operation and increase their efficiency. These may include electrodes, EKG sensors, unipolar or ablation electrodes, impedance based contact sensors, and thermistors, to name a few. So a big part of balloon catheter manufacturing involves embedded and stretchable electronics.

Your Balloon Catheter Partner

At Quasar, we have accumulated  the ability to execute complex balloon catheter assemblies, mounting elements on or inside the balloon. If you are considering developing a balloon catheter or seeking a solution to a specific challenge with your existing balloon catheter Contact us to discover how you can benefit from our know-how and experience.