A coronary atherectomy system with a novel burr design for two-phase operation

A coronary atherectomy system (CAS) was developed with a novel burr designed for a two-phase atherectomy procedure: low-speed drilling for lesion crossing and high-speed orbiting to achieve luminal gain, to removal the stenosis in artery.

To investigate the CAS mechanism and validate its efficacy and safety.

Engineering bench-top testings were conducted to evaluate the burr crossing time, luminal gain, debris size, temperature rise, and grinding force together with in-vivo and ex-vivo swine studies.

The bench-top engineering testing results showed that the CAS can expand the calcified lumen diameter from 0.4 to 1.7 mm and the debris size, temperature rise, and grinding force were relatively low and safe. In the in-vivo swine study, the media and internal elastic membrane remained intact. The intima of the artery was removed at the 0-day follow-up and re-growthed at the 30-day follow-up. No abnormal phenomenon in the digital subtraction angiography, blood testing, ECG, and anatomy analysis were found. The ex-vivo study, by inserting a plaque surragate (graphite) into the coronary artery, showed similar efficacy in luminal gain and safety.

This study demonstrated the efficacy and safety of CAS device with the novel two-phase burr design.