Keeping up with doctor speak can be a full time job (even for doctors). I blogged about this previously entitled: STEMI, ADHF, MVO, VTE, CSL: The moving target of acronyms in cardiology
The treatment of severely narrowed aortic valves with a catheter rather than surgery had been called Transcather Aortic Vave Implantation (TAVI) since the old valve is not repalced - the new valve is placed or implanted inside the old one. The cardiology journal JACC decided to rename this TAVR for replacement instead of implant even though there is no replacement. If you missed this arbitrary switch it's OK since they have decided to switch back. Sometimes being behind the news curve is more efficient. For now, we can say TAVR was the old term before we switched back to the older term TAVI. What's old is new again.