Ablation of supraventricular tachydysrhythmias with direct and radiofrequency current

: Ablation therapy of tachycardias refractory to pharmaceutical preparations is considered in recent years the method of choice. In the submitted paper the authors give an account of 12 years experience with ablation treatment of supraventricular tachycardias. The group comprises 23 patients, who were subjected to ablation therapy by radiofrequency current (RF) on account of relapsing supraventricular dysrhythmias, resistant to medicamentous treatment (between May 1994 and February 1996). The mean age of the patients was 60.4 +/- 9.2 years. The historical control group is formed by 13 patients who were subjected to ablation of the AV junction by direct current (DC) between March 1984 and April 1994, their mean age being 68.4 +/- 10.4 years. After DC ablation the operation was successful in 8 cases (62%) where complete AV block was achieved, while it was partially successful in two cases where modification of the conductivity was achieved (15%) and it failed in three cases (23%). The levels of AST and CK enzymes at the investigated time intervals are significantly higher than in the RF method. During RF ablation the mean duration of successful ablation sequence was 36 s, the mean energy 1 042 +/- 726 J, the median number of sequences was 10.5. In ablation of the AV junction the success was 95%. In one of two patients who were subjected to ablation of arterial flutter a relapse of tachycardia was recorded after an interval of 24 hours. Subsequently complete ablation of the AV junction was performed. In a female patient with atrioventricular reciprocal tachycardia due to a latent accessory pathway in the area of the free left ventricular wall temporarily tachycardia could not be induced, however, after discharge from hospital the paroxysms of supraventricular tachycardia with a substantially lower frequency reappeared. Comparison of the two methods does not suggest a significant difference of their effectiveness, the RF method causes, however, less extensive myocardial damage.