[The surgical treatment of nodal reentry tachycardia. The late results].

Purpose: To analyze the long-term results of surgical treatment of atrioventricular nodal reentrant tachycardia (AVNT).
Methods: From March 1987 to March 1990, 20 patients with AVNT were submitted to surgical therapy, 14 female, aged 12 to 70 (42.8 +/- 17) years. All presented crisis of AVNT from 6 months to 60 (18.4 +/- 15.9) years. Ten of them had syncope or near syncope and two with cardiac arrest during reversion of AVNT with antiarrhythmic drugs. They used 1 to 6 (3.75 +/- 1.45) antiarrhythmic drugs before surgery. The electrophysiologic study (EPS) showed the common form of AVNT in all cases. The surgical procedure was anatomically directed to the posterior area of the AV node. Programmed atrial stimulation (PAS) were applied on 18 patients after surgery. The long-term results were analysed by clinical evaluation, EPS and Holter when they were necessary.
Results: The postoperative PAS was done in 18 patients and did not induce any AVNT, even after atropine IV. The PR interval was 153 +/- 50 ms before and 152 +/- 38 ms after surgery (p > 0.05). During follow up (26 +/- 10 m) there were not AVNT recurrence. Two patients developed chronic atrial fibrillation after 24 months of surgery.
Conclusion: The perinodal dissection technique used was safe and successful to treat AVNT, preserving AV nodal conduction.