Catheter ablation is a common treatment for ar- rhythmia and the number of procedures is increasing. Takatsuki General Hospital introduced a remote mag- netic navigation system into clinical practice for the first time in Japan. This system produces- magnetic flux density of 0.08-0.1 Tesla. Catheter ablation is usu- ally performed under deep sedation at our facility ; however, general anesthesia is needed in some cases. Although many cases of general anesthesia for MRI have been reported, there has been no report of gen- eral anesthesia under the unique environment of a weak magnetic field. We use MRI-certified equipment such as an anesthesia machine and a patient monitor in the heart rhythm center. There is no contraindication for the selection of anesthetic agents. Analgesia, depending on pain or burning sensation by ablation, and immobilization are required. Anesthesiologists must be aware that there are some differences in gen- eral anesthesia in the MRI room compared with the heart rhythm center, including the environmental set- ting, limitations in the use of certain medical equipment and procedure-related knowledge.