A heart pacemaker detects pace-terminable tachycardia conditions in the atrium of the heart in accordance with selected high rate, rate stability, sudden onset and sustained high rate criteria. When a pace-terminable tachycardia is detected, programmed treatment modalities are applied to attempt to terminate the tachycardia. The tachycardia is treated by applying timed bursts of electrical pulses in formats defined by programmed primary and secondary treatment modalities. The primary and secondary treatments may be applied in an order which is dependent upon the prior successful treatment of similar tachycardias. The pacemaker may also utilize remembered treatment values which were successfully applied to treat similar tachycardias. The pacemaker may be programmed to restart the primary and secondary modes of treatment in the event that the modes initially failed to terminate a tachycardia. The pacemaker may also be programmed to limit the rate of burst pulses to avoid overstimulating the heart.