A cardiac pacing and irreversible electroporation (IRE) apparatus includes a pulse generator and a shaping circuit. The pulse generator is configured to generate IRE pulses of prespecified shape and repetition rate. The shaping circuit is configured to convert some of the IRE pulses into pacing pulses of prespecified frequency and amplitude, to generate an output signal including ones of the IRE pulses interleaved with ones of the pacing pulses, and to output the output signal to a probe in a heart of a patient for applying the output signal to cardiac tissue.