Characteristics of the Ablation Index when performing «high power» radiofrequency ablation in patients with ischemic ventricular tachycardias

Introduction. Radiofrequency catheter ablation (RFA) is a routine method of surgical treatment of ventricular arrhythmias. The criterion for evaluating the effectiveness of RF exposure in such procedures is not defined. The article describes the use of the “Ablation Index” (AI) parameter to assess the optimal damage to the arrhythmogenic substrate during RFA with “high power” radiofrequency exposure in patients with ventricular tachycardias (VT). Aim: to determine the effective Ablation Index in RFA with an exposure power of 50 watts. in patients with VT and structural heart disease. Methods. Patients with structural heart disease and VT refractory to conservative therapy underwent RFA with RF energy exposure power of 50 W. When mapping the substrate, bipolar mapping was performed with standard settings (normal tissue >1.5 mV and scar tissue <0.5 mV) and, in some cases, was supplemented by activation mapping and mapping using the “intrimant” phenomenon. Results. 63 patients with symptomatic VT were treated, 66.7% were men (n = 42). The mean age of the patient was 58.8 years. The duration of history of VT was 35.1 months on average. History of revascularization was in 36.5% (n = 23) of patients. There were no complications during the operation and in the postoperative period. The overall effectiveness of the operation after 12 months. was 82.6% (n = 52). The average value of AI in patients with remissions of VT after surgery for 12 months. amounted to 494.9. The average value of AI in patients with remissions of VT after surgery for 12 months. amounted to 494.9. The mean value of AI in patients with recurrent VT was 383.2. Conclusion. The AI indicator can be used as a criterion for evaluating the effectiveness of arrhythmogenic myocardial damage in patients with VT.