How Zeus is pushing the envelope in microcatheter design
As the number of minimally invasive surgeries continues to grow, health care professionals continue to seek new and better tools to deliver the best care for their patients. Leading development in this area is a keen interest in smaller or microcatheter designs for endovascular catheterisation procedures, as Kevin J. Bigham, PhD., technical writer for Zeus explains.
Enhancements in miniaturised devices can lead to improved efficiency and effectiveness and reduced trauma for patients. Microcatheters address a broad portion of endovascular disorders including peripheral artery disease (PAD) and neurovascular disease because of their ability to access smaller vasculatures. Access to these small vessels presents obvious size limitations for the device but also for intraluminal catheter technologies such as intravascular ultrasound (IVUS), atherectomy devices, cameras, and fibre optics. Recently, Zeus Industrial Products, Inc., (headquartered in Orangeburg, SC, USA) has developed an extremely thin-walled PTFE catheter base liner to address microcatheter design and vascular access. This product features a maximum liner wall thickness of 0.01905 mm (0.00075″) and is the thinnest catheter base liner made to date. With such extremely small dimensions, this PTFE catheter liner creates greater lumen potential and allows for a smaller overall finished catheter device.
The 0.01905 mm (0.00075″) maximum wall liner is an improvement over earlier generations of this extrusion technology. Previously, thin-walled PTFE extrusions as catheter liners were generally limited to walls no thinner than 0.025 mm (0.001″) and lacked certain mechanical consistencies for very-fine-tuned or precision applications. In addition to a proprietary process, the new 0.01905 mm (0.00075″) liner, called StreamLiner XT by Zeus (part of the Zeus StreamLiner series), achieves a consistent wall thickness by stretching or drawing down the liner after it is placed over the mandrel during catheter construction. The draw-down process fits the liner snugly over the mandrel for secure and repeatable construction. Furthermore, and through the manufacturer’s exclusive technology, the 0.01905 mm (0.00075″) wall liner possesses significant strength and toughness despite its extremely thin nature. For catheters made with this new liner, mechanical attributes such as torsional response, flexibility, and stiffness appear to meet the criteria necessary for use with fine vascular procedures.
There are other benefits to using PTFE when it can be extruded to meet such microcatheter requirements. PTFE has an extremely low surface friction – a highly desirable trait for a catheter lumen. The low surface friction is also more uniform because it is an extrusion followed by a manual draw-down. Low surface friction of the catheter lumen reduces the deployment force (minimises resistance) for various intraluminal catheter technologies like those cited earlier. For more delicate catheter-deployed devices such as stents, the lower and uniform lumen wall friction minimises the potential for collapse of the stent before reaching its destination. On the whole, this highly lubricious thin-wall extruded lumen presents many attractive features over existing similar technologies and products.
Finally, there are the salient advantages of using a smaller device. Minimally invasive surgical procedures (MISPs) are almost always preferred versus open surgeries because MISPs significantly reduce trauma to patients. Reduced trauma speeds healing for patients, reduces hospital stays, and reduces the overall healthcare burden for that patient. Considering the prevalence of chronic endovascular diseases in nearly all modern societies, technologies that reduce trauma further still, such as the 0.01905 mm (0.00075″) liner appears poised to do, are always in demand. Moreover, the ability to produce ever smaller microcatheters allows access to the smallest vasculatures, even those approaching the smallest neurovascular networks. With greater access come expanded options for MISPs versus open surgeries. These smallest micro-devices also lay the groundwork for possibilities of innovative catheter technologies which have yet to be conceived.