Toward Variable-Friction Catheters Using Ultrasonic Lubrication

Minimally invasive endovascular procedures use catheters that are guided through blood vessels to perform interventions, resulting in an inevitable frictional interaction between the catheter and the vessel walls. While this friction enhances stability during the intervention, it poses a risk of damaging the inner layer of the blood vessel wall during navigation, leading to post-operative complications including infectious diseases and thrombus formation. To mitigate the risk of adverse complications, we propose a new concept of a variable-friction catheter capable of transitioning from low friction during navigation to high friction for increased stability while performing the intervention. This variable-friction catheter leverages ultrasonic lubrication to actively control the frictional forces experienced by the catheter during the procedure. In this paper, we demonstrate a proof-of-concept for a friction control module, a pivotal component of the proposed catheter design. Our experiments demonstrate that the prototype effectively reduce friction by up to 11% and 60%, on average, on soft and rigid surfaces, representing its potential performance on healthy and calcified tissue, respectively. This result underscores the feasibility of the design and its potential to improve the safety and efficacy of minimally invasive endovascular procedures.