system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Most cardiotoxic local anesthetic
assistant
The correct answer is  Bupivacaine is the most cardiotoxic LA (Ropivacaine is a newer bupivacaine congenial with less cardiotoxicity).(Refer: stoelting's pharmacology and physiology in anaesthetic practice, 5th edition, pg no.294)