Sharpe M D, Cuillerier D J, Lee J K, Basta M, Krahn A D, Klein G J, Yee R
Department of Anaesthesia, London Health Sciences Centre, University Campus, University of Western Ontario, Canada.
Anesthesiology. 1999 Jan;90(1):60-5. doi: 10.1097/00000542-199901000-00010.
The effects of sevoflurane on the electrophysiologic properties of the human heart are unknown. This study evaluated the effects of sevoflurane on the electrophysiologic properties of the normal atrioventricular conduction system, and on the accessory pathways in patients with Wolff-Parkinson-White syndrome, to determine its suitability as an anesthetic agent for patients undergoing ablative procedures.
Fifteen patients with Wolff-Parkinson-White syndrome undergoing elective radiofrequency catheter ablation were studied. Anesthesia was induced with alfentanil (20-50 microg/kg) and midazolam (0.15 mg/kg), and vecuronium (20 mg) and maintained with alfentanil (0.5 to 2 microg x kg(-1) x min(-1)) and midazolam (1 or 2 mg every 10-15 min, as required). An electrophysiologic study measured the effective refractory period of the right atrium, atrioventricular node, and accessory pathway; the shortest conducted cycle length of the atrioventricular node and accessory pathway during atrial pacing; the effective refractory period of the right ventricle and accessory pathway; and the shortest retrograde conducted cycle length of the accessory pathway during ventricular pacing. Parameters of sinoatrial node function included sinus node recovery time, corrected sinus node recovery time, and sinoatrial conduction time. Intraatrial conduction time and the atrial-His interval were also measured. Characteristics of induced reciprocating tachycardia, including cycle length, atrial-His, His-ventricular, and ventriculoatrial intervals, also were measured. Sevoflurane was administered to achieve an end-tidal concentration of 2% (1 minimum alveolar concentration), and the study measurements were repeated.
Sevoflurane had no effect on the electrophysiologic parameters of conduction in the normal atrioventricular conduction system or accessory pathway, or during reciprocating tachycardia. However, sevoflurane caused a statistically significant reduction in the sinoatrial conduction time and atrial-His interval but these changes were not clinically important. All accessory pathways were successfully identified and ablated.
Sevoflurane had no effect on the electrophysiologic nature of the normal atrioventricular or accessory pathway and no clinically important effect on sinoatrial node activity. It is therefore a suitable anesthetic agent for patients undergoing ablative procedures.
七氟醚对人体心脏电生理特性的影响尚不清楚。本研究评估了七氟醚对正常房室传导系统以及预激综合征患者旁路电生理特性的影响，以确定其作为接受消融手术患者麻醉剂的适用性。
对15例接受择期射频导管消融术的预激综合征患者进行研究。麻醉诱导采用阿芬太尼（20 - 50微克/千克）和咪达唑仑（0.15毫克/千克），维库溴铵（20毫克），并以阿芬太尼（0.5至2微克·千克⁻¹·分钟⁻¹）和咪达唑仑（根据需要每10 - 15分钟给予1或2毫克）维持麻醉。通过电生理研究测量右心房、房室结和旁路的有效不应期；心房起搏时房室结和旁路的最短传导周期长度；右心室和旁路的有效不应期；以及心室起搏时旁路的最短逆向传导周期长度。窦房结功能参数包括窦房结恢复时间、校正窦房结恢复时间和窦房传导时间。还测量了心房内传导时间和心房 - 希氏束间期。对诱发的折返性心动过速的特征，包括周期长度、心房 - 希氏束、希氏束 - 心室和心室 - 心房间期，也进行了测量。给予七氟醚使呼气末浓度达到2%（1个最低肺泡浓度），并重复研究测量。
七氟醚对正常房室传导系统或旁路的传导电生理参数以及折返性心动过速期间均无影响。然而，七氟醚使窦房传导时间和心房 - 希氏束间期在统计学上显著缩短，但这些变化在临床上并不重要。所有旁路均成功识别并消融。
七氟醚对正常房室或旁路的电生理特性无影响，对窦房结活动也无临床重要影响。因此，它是接受消融手术患者的合适麻醉剂。
