Objective To observe preserving effect on myocytes in porcine aortic valve replacement with minimal extracorporeal circulation (MECC). Methods 7 pigs were collected as experimental animals and undertook aortic valve replacement with MECC. Morphological and immunofluorescence intensity changes of right atrial and left ventricular tissues were observed. Results HE staining showed that there were not significant changes and edema or injury of myocytes of right atriums and left ventricles between preoperation and postoperation. Immunofluorescence staining showed complement C3b/c in right atrial myocardial tissues after the operation were a little ber, and innate antibody IgG were a little ber in left ventricular myocardial tissues but similarly weak in right atrial myocardial tissues pre- and post-operation. There was not significant changes in HSPG staining in pre-and post-operative right atrial myocardial tissues, but HSPG were obviously weaker in left ventricular myocardial tissues after the operation. Conclusion MECC is effective on support of porcine aorta valve replacement.