Experimental investigation on low-frequency vibration-assisted cutting of calcified tissue during rotational atherectomy

Rotational atherectomy (RA) is an effective minimally invasive treatment for severe coronary calcification, but it carries risks of vessel injury due to high mechanical and thermal loads. This study proposes a low-frequency vibration-assisted rotational atherectomy (LFVARA) technique that reduces cutting force and temperature rise by promoting cyclic disengagement between the tool and tissues. Experimental trials compared LFVARA against RA using bone cement as a calcified plaque phantom, with vibration parameters systematically varied across amplitudes (20–50 μm), frequencies (50–150 Hz), and rotational speeds (60000–120000 r/min). Response surface methodology based on a Box-Behnken design is employed to analyze parameter interactions and identify optimal conditions. Results show that increasing vibration frequency from 50 to 150 Hz at 50 μm amplitude prolongs non-cutting time per cycle by 19.47%, while raising rotational speed from 60000 to 120000 r/min at 50 μm/150 Hz reduces it by 26.59%. Under 120000 r/min/150 Hz/50 μm conditions, LFVARA mitigates mean cutting force by 23.85% and temperature rise by 29.24%, as validated by force-thermal metrics. The optimized parameter set (60000 r/min, 141.6 Hz, 49 μm) is experimentally validated with less than 10% error in force and 5% in temperature prediction. The findings demonstrate that LFVARA can effectively reduce the average cutting force and temperature rise during the process of removing calcified tissues. This work presents a promising approach for coronary atherosclerosis treatment, offering a novel method to optimize therapeutic efficacy.