Ideal Anesthetic Agent for Cardiac Electrophysiology Study and Catheter Ablation – A Pilot Study

Objectives: Patients suffering from supraventricular tachycardia (SVT) require diagnostic or therapeutic intervention in a cardiac electrophysiology (EP) laboratory. Some anesthetic medications may adversely affect cardiac EP and conduction, altering the ability to induce the arrhythmia, and may have a negative impact on the ablation treatment. This prospective, randomized, pilot study was conducted in the cardiac EP laboratory of a tertiary care hospital with the aim to identify the ideal anesthetic agent for cardiac EP study and catheter ablation of SVT. The primary objective was to compare the effects of anesthetic agents on cardiac electrophysiological parameters and arrhythmia inducibility. The secondary objective was to compare the patient, anesthesiologist, and cardiologist satisfaction scores with respect to the anesthetic agent used. Materials and Methods: Thirty adult patients with SVT for EP study and radiofrequency catheter ablation were administered either of the anesthetic agents: midazolam, fentanyl, propofol, ketamine, or sevoflurane titrated to produce conscious sedation corresponding to bispectral index (BIS) values between 71 and 90. Electrophysiological parameters were recorded before and after administering the anesthetic agent. Results: Arrhythmia could be induced in all patients. Although electrophysiological parameters remained stable with ketamine administration; higher values of the Richmond Agitation Sedation Scale score and BIS were recorded. Propofol and sevoflurane administration was associated with deviation in electrophysiological parameters more than fentanyl and midazolam. The highest values of patient, anesthesiologist, and cardiologist satisfaction scores were obtained in the fentanyl group and the lowest in the ketamine group ( P < 0.002). Conclusion: In doses used to provide conscious sedation, fentanyl provided ideal conditions, and midazolam, propofol, sevoflurane, and ketamine provided satisfactory conditions for conducting EP study and catheter ablation for supraventricular tachyarrhythmias. The potential of propofol to impede cardiac conduction needs to be explored further.