The use of programmed stimulation in the long-term treatment of re-entry tachycardia offers encouraging perspectives. Among the others proposed the "scanning" system seems to be the most effective. However, an implantable stimulator with such pictures is not yet available and a temporary electrode is thus required. These difficulties have been overcome utilizing the radiofrequency as a sincronizing and stimuli-producing means. An implantable appliance was therefore designed which is triggered by the patient himself and automatically researches the zone of interruption of tachycardia by exploring the R-R cycle. The program of external transmitter which can produce one or two sincronized impulses, seams the cycle with progressive steps of 10 msec each; when tachycardia is interrupted, further stimulation is inhibited. The implanted part of the appliance connected with a normal endocavitary electrode, does not have any power supply and thus is very small. The efficacy of this method has been shown in 4 junctional reciprocating and 1 ventricular recurrent chronic tachycardias, resistent to conventional pharmacologic therapy.