Elastohydrodynamic lubrication in rotational atherectomy: Fluid film thickness characteristics and reduction of vascular damage risk

In rotational atherectomy, a fluid film separates rotating burr and blood vessel, preventing vascular damage and involving elastohydrodynamic lubrication (EHL). Investigating fluid film thickness is necessary, as insufficient thickness increases vascular damage risk. This study examined damage depth on vascular phantom, revealing fluid film thickness characteristics and trends are similar to classical point contact EHL. The influence of burr and vascular phantom geometry was discussed with classical point contact EHL analysis, leading to a strategy: increasing burr’s radius on tangential direction that can reduce damage risk by thickening fluid film. The findings demonstrate that classical point contact EHL provides valuable insights into this fluid film and can guide strategies for reducing vascular damage risk by improving fluid film thickness.