There are multiple definitions:

1. Chinese Academy of Social Sciences(English)

   • CAS
   • Social aspects, Organization (management)

2. computer assisted surgery system(English)

   • TAD
   • Surgery, Computer Assisted Diagnosis, Bioengineering
   • https://doi.org…ury.2016.07.018

3. Coronary Artery Surgery Study(English)

   • CABG, LVEF, LVESVi, STICH, SVR
   • Coronary circulation, Surgery, Clinical trials
   • https://doi.org…cvs.2004.07.060