RADIOFREQUENCY-CURRENT CATHETER ABLATION OF VENTRICULAR-TACHYCARDIA

Since its introduction into clinical practice in 1982, catheter ablati on has evolved as a first-line mode of non-pharmacological therapy in patients with atrioventricular nodal reentrant tachycardia and in pati ents with atrioventricular tachycardia involving an accessory pathway. The initial experience was based on the use of direct current for abl ative purposes. However, since severe complications have been observed using this energy source, radiofrequency (RF) current catheter ablati on is now the most frequently used technique. Efficacy rates are high (> 80%) in patients with idiopathic ventricular tachycardia and bundle -branch reentrant tachycardia. In addition, the technique also has a r elatively high acute success-rate in patients with incessant ventricul ar tachycardia. However, RF current catheter ablation is less effectiv e in patients with drug-resistant, chronic, sustained ventricular tach ycardia after myocardial infarction or in the presence of dilated card iomyopathy. Further improvements which include new criteria for the lo calization of the origin of ventricular tachycardia as well as technic al improvements are particularly needed in this subgroup of patients. Thus, RF current catheter ablation in patients with ventricular tachyc ardia can be considered a promising new mode of non-pharmacological th erapy. The efficacy rate of the procedure is highly dependent on the p resence and type of organic heart disease as well as the mechanisms un derlying ventricular tachycardia. Due to the limited experience, espec ially with respect to the long-term results, RF current catheter ablat ion is still an experimental mode of antiarrhythmic treatment.