Tachycardia reversion pacer

There is disclosed a tachycardia control pacer in which there is generated a sequence of pacing pulses at intervals which are a function of the effective refractory period intrinsically associated with the rate of the patient heartbeats. If the tachycardia episode is not terminated, another sequence of pulses is generated; however, the rate of the new sequence is decreased if at least one unevoked heartbeat was sensed during the preceding pacing pulse sequence and the rate is increased in the absence of any unevoked heartbeat having been sensed during the preceding pacing pulses sequence. Also, in order to smooth the transition between the fast pulses used to terminate the tachycardia episode and subsequent beating in sinus rhythm, pacing pulses continue to be generated at increasing pacing intervals until they merge into standby pacing.