A method for heart treatment includes analyzing the cardiac rhythm. The method further includes utilizing a generator to produce discharges (Si) of N pulses (I) of VNS stimulation in succession. The discharge may be synchronized to a detected R ventricular depolarization wave of each cardiac cycle. The method further includes controlling a stochastic modulation of the discharges control of the delivery of each VNS pulse of each discharge by selective inhibition or not of the generation of these VNS pulses. The number of pulses of each discharge thus randomly varies, and thus varies the VNS stimulation energy of this discharge, which is artificially induced, cycle-to-cycle variability in the RR interval. This stochastic therapy is applied if the spontaneous heart rate variability falls below a minimum level.