Meta-Poly® Featured in MPO

Ross Peterson • Vice President, Business Development, ProPlate®
Craig Ingalls • President and CEO, ProPlate®

​Catheters are long, flexible, thin-walled, extruded polymer tubes—often with braid reinforcements—that can be navigated and guided through the body’s veins or arteries to enable access to areas in need of treatment. This minimally invasive approach allows for reduced trauma to the patient’s body and faster recovery from surgery. Balloon catheters are often utilized in procedures including angioplasty, stent placement, and those that utilize heating or cooling. Further, they are used in the treatment of peripheral artery disease, atrial fibrillation (AF), and neural and other endovascular conditions. During most of these procedures, once the balloon is deployed, it inflates, pressing and conforming to the surrounding tissue to open blood vessels or valves. Catheters may also be used to contact tissue for other application-specific purposes, such as tissue ablation or stimulation.

Today’s catheter ablation and stimulation procedures can take up to several hours. Current balloon catheter designs in the market have a variety of limitations, from both a functional and manufacturability standpoint. For example, a critical drawback is associated with designs delivering a constant temperature across the entire surface of the balloon. This approach leaves little room for the differences in tissue walls and other anatomy being ablated or stimulated, and can lead to over- or under-ablation/stimulation. This is directly tied to the current design and manufacturing processes for these devices.

Traditionally, catheter ablation has a success rate in AF procedures of about 60 percent. Further, it is not uncommon for patients to undergo multiple ablation procedures in order to achieve a successful treatment. According to the CDC, an estimated 2.7 million to 6.1 million people in the United States have AF, which can lead to blood clots, stroke, heart failure, and other heart-related complications. This disease alone drives a greater need for further catheter technology advancement in order to best help patients in need of more effective treatments.

Until recently, thermal management designs for balloons have primarily involved hot or cold liquids or gases circulating within the balloon and supplied via two or more lumens within the catheter shaft. As previously mentioned, a constant temperature distributed along the entire surface of the balloon will, in many instances, limit the effectiveness or functionality of the device.

A new coating process technology allows for discrete and high temperature variation at localized points of contact on the balloon surface. This is accomplished with the application of multiple, electrically independent electrodes metallized directly onto the outside surface of off-the-shelf catheter balloons made of various polymers. These conductive surface patterns can be used in high-temperature applications where an external RF energy source is employed. This patterned metalizing process offers companies an alternative design and manufacturing option aimed to optimize functionality and versatility for electrophysiology (EP) balloon catheter devices.

Through the use of this novel metallization technology, interventional cardiologists can deploy robust electrical energy through multiple paths and to multiple discrete locations via minimally invasive catheter-based components. This enables more sophisticated and effective treatment of diseases and disorders such as, but not limited to, arrhythmias.

Over the past few years, ProPlate’s team of physicists, chemists, material scientists, and electrical/mechanical engineers have successfully integrated metal electrode and radiopaque materials, as well as electrical lead paths, directly onto standard balloon catheters. The technology has also been successfully demonstrated on ceramic components, thin-walled polymer tubing, metallic stents, and other miniature catheter components.

​Medical device manufacturers can utilize this flexible, ultra-thin metallization technology to precisely and selectively install electrodes, electrical leads, and radiopaque markers directly onto catheter components. Potential application areas include diagnostics, detection, sensing, ablation, stimulation, guidance, and mapping. The novel, patent-pending process technology provides for selective metallization, which is attached intimately to the polymer surface, and demonstrates excellent adhesion and flexibility without fracturing, lead separation, or delamination. The process accommodates high-inflation pressure, high balloon expansion multiples, folding, twisting, and bending over a broad range of balloon dimensions and geometries. Until now, placing such electrical components on an extensible surface was not possible using traditional manufacturing methods.

Advances in balloon catheter design and functionality via utilization of this coating technology offer enhanced treatment possibilities. In sensing and mapping applications, for example, the process facilitates transmission of multiple data streams over small-diameter catheter tubing and components, allowing for mapping of electrophysiological activity with high resolution while also eliminating, or greatly reducing, the requirement for multiple and discrete lead wires. It also eliminates the need for extensive lead insulation and the associated “wasted diameters” from the dimensional growth. This diameter-reducing technology will allow for increased functionality for ever-shrinking catheters.

The large size, 2D-geometry and rigid mechanical properties of standard conventional electronics—such as PCB flex circuitry or nanoparticle conductive inks (which can be prone to cracking and delamination)—integrated into medical devices can result in many drawbacks and procedural challenges with soft biological tissue. Through this advancement in manufacturing, device engineers can construct electronics that can readily integrate with the soft, irregular curvilinear surfaces of the human body.

Through this proprietary process, expandable circuitry is selectively applied onto the complex 3D geometry of a balloon catheter and/or its subcomponents. Further, it can be made to be extensible without tensile or compressive cracking failures by utilizing non-linear geometrical layouts. High adhesion strength and robust flexibility enable multiple dynamic inflation and deflation cycles during use. Employing this novel coating technology on catheter shafts can significantly reduce the size of catheter lumens, enabling reach to biological locations not previously accessible, while dramatically enhancing sensing possibilities. Similar concepts are also made possible when applied to other substrates, such as ceramics, industry standard metals, and in some cases, bioabsorbable materials.

The unique capabilities of this technology create new opportunities for doctors and physicians studying tissues, improving surgical procedures, and monitoring patient wellness by driving further valuable medical device application innovations.

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