In this paper, the results of the papillary myotomy and septal tricuspid valvotomy were studied. The 19 dogs were randomly divided into four groups so as to observe the blood supply, healing course, strength and functions of the anterior papillary muscle. It was confirmed that the traumatic rupture of the papillary muscle should be repaired early. In the clinic 31 patients of ventricular septal defect with tricuspid valve pouch were treated by the approach with septal valvotomy and cone papillary myotomy of tricuspid valve. The successful rate of VSD repair was up to 100%. Therefore, this approach is worthy to be used clinically.