The present invention relates to an assembly for replacing a heart valve or to a coronary angioplasty assembly, comprising an introduction sheath (13) for an introducer (1) or for a delivery catheter (1′；), which is smaller compared to an introducer, intended to be introduced into an artery of a human body. The invention basically comprises: either integrating the metal support of an electrode of the cardiac stimulator into a part to be fitted around the introduction sheath that is introduced into the artery of a patient or into a guide wire that becomes a bipolar electrode support； or connecting the cathode of an external cardiac stimulator to the guide wire of an artificial valve and the anode to a transcutaneous electrode in contact with the skin of the patient.
