[Refractory tachycardia treated with fine catheter ablation of left sided-accessory pathway]

In 10 patients with incessant A-V reciprocating tachycardia (AVRT), catheter ablation (CA) of left-sided accessory pathway (AP) was attempted with DC shock using a fine quadripolar electrode positioned in the coronary sinus (CS) close to the AP. 3-6 cathodal shocks of 50 to 150 J (stored energy) were delivered (cumulative energy 150-700 J/Pt). After a follow-up period of 9-20 months (including EP restudying), AVRT were cured in 8 cases, AP conduction resumed in 2 (less episodes of AVRT in 1 case). The high success rate may be the result of using the special lead (tolerate multiple shock without decrease in the intensity of the shock, cause less barotrauma). The indications and complications of the technique were also discussed.