Arrhythmia and conduction disorders can be treated by intracardiac ablation. The paper presents an original intracardiac catheter ablation method using a high-frequency (HF) electromagnetic power source. A high-frequency signal is emitted through an electrophysiological catheter introduced into the femoral vein and passed along the course of that vein into the heart. To prevent impedance rise, a problem encountered with other techniques, HF signal wave trains are used for half-period impedance match control and, where necessary, automatic impedance adjustment. Fully automated impedance matching combined with frequency-specific catheter design prevents power reflection between load and source. Resulting lesions can be controlled as to location, area and depth. In addition, HF pulses can be released independently of cardiac rhythm. Additional comprehensive animal experimentation is currently going forward.