摘要
BACKGROUND The R-on-T phenomenon is a malignant arrhythmia associated with potentially catastrophic consequences.It may initiate ventricular tachycardia or ventricular fibrillation,which can result in syncope or sudden cardiac death.This manifestation poses a great challenge for anesthesiologists.However,it is rarely encountered in the perioperative setting.CASE SUMMARY We herein present a case in which the R-on-T phenomenon was incidentally revealed by 24-h Holter monitoring in a patient diagnosed with sigmoid colon cancer.Careful evaluation and treatment with mexiletine were carried out preoperatively under consultation with a cardiovascular specialist,and surgery was uneventfully performed under general anesthesia after thorough preparation.CONCLUSION Physicians should be vigilant about this infrequent but potentially fatal arrhythmia.Our experience suggests that the anesthetic process can be greatly optimized with careful preparation.