A test bench assembly for simulating cardiac surgery includes a passive heart having at least one pair of cardiac chambers with an atrial chamber and a ventricular chamber. A reservoir is adapted to house working fluid. A pressure generator fluidically connects both to the ventricular chamber of the passive heart and to the reservoir. A pressure regulation device provides working fluid in input to the atrial chamber with preload pressure, and working fluid in output from the ventricular chamber with afterload pressure. The pressure regulation device fluidically connects both to the atrial chamber of the passive heart and to the ventricular chamber of the passive heart. The pressure regulation device has a single compliant element for each pair of cardiac chambers, which provides working fluid with both preload, and afterload pressures.