RESUMO
The effects of dexmedetomidine sedation upon the electrophysiologic [EP] properties of normal atrioventricular [A-V] and accessory pathway [AP] conduction were studied in twenty five patients with Wolff-Parkinson-White [WPW] syndrome during accessory pathway cryoablation in cardiac catheterization laboratories [CCL]. The presence of an AP was confirmed by baseline EP studies. Sedation was induced in 25 patients using dexmedetomidine [Imcg/kg] over 10 minutes and maintained with dexmedetomidine infusion [0.2 to 0.7 mcg/kg/hr]. A baseline EP study was performed which consisted of effective refractory period [ERP] and shortest cycle length [SCC] measurement during antegrade conduction in the normal A-V pathway and AP, as well as during retrograde conduction in the AP. Comparison with baseline EP studies indicated that the administration of sedation had no effect upon conduction or ERP in either patlway. Haemodynamic, blood gases showed no significant changes throughout the ablation procedure with no development of dysrrhythmia. We conclude that dexmedetomidine sedation is suitable for patients undergoing ablative procedures for accessory pathways in cardiac catheterization laboratories [CCL]