Transesophageal atrial pacing in the management of re-entry supraventricular tachyarrhythmias occurring during general anesthesia

Background. Supraventricular tachyarrhythmias (SVTs) represent an intraoperative risk factor that should be always prevented/managed. The commonly used anti-arrhythmic drugs are accompanied by intrinsic hazards, such as pro-arrhythmic and toxic effects or unpredictable onset and duration of action. We underline the therapeutic use of transesophageal atrial pacing (TAP) for the interruption of particular re-entry SVTs occurred during surgical procedures in general anaesthesia. Methods. Our study was carried out in 25 patients characterized by a personal clinical history of transient tachyarrhythmic episodes, subjected to general anaesthesia obtained by midazolam, propofol, N2O e O2, sevoflurane, fentanil and vecuronium bromide. We used TAP bursts of 3-5 sec, their minimal pacing rate being equivalent to the tachyarrhythmia cycle length, with an impulse intensity ranging from 18 to 25 mA. In such conditions, the re-entry was interrupted by the induction of refractoriness of the wave-front that sustained the underlying arrhythmogenic circuit. Results. During the study, the following arrhythmias occurred in 7 out of all patients: 1 type I atrial flutter, 3 nodal tachycardias, 1 antidromic and 2 orthodromic atrioventricular tachycardias, respectively. TAP assured either atrial capture or prompt suppression of arrhythmias in all cases. Low intensity impulses did not ever allow ventricular capture. Conclusions. TAP can be considered as a valid therapeutic device for the management of re-entry SVTs occurred during general anaesthesia, resulting it effective, safe and easy-practicable.