Objective To investigate the relationship between the Angle of occlusion approach and the success rate of operation and intracardiac operation time of transthoracic minimally invasive perventricualr device closure of perimembranous ventricular septal defects (pmVSD) guided by transesophageal echocardiography (TEE). Methods The images and case data of 73 patients with TEE guided transthoracic minimally invasive pmVSD occlusion were retrospectively analyzed. The correlation between the Angle of occlusion approach and the time of intracardiac operation was analyzed. Patients were divided into two groups according to the included the Angle of the occlusion approach and the successful situation of the operation: one group included the Angle of the occlusion approach < 30°

and the other group included the Angle of the occlusion approach ≥30°

and the surgical success rate and intracardial operation time of the two groups were compared. Results There was a positive correlation between the Angle of occlusion approach and the time of intracardiac operation (rs =0.786

P < 0.05). The success rate of the occlusion approach < 30° group was higher than that of the ≥30° group (100% VS 80.95%

?2=11.251

P < 0.05). Intracardial operation time in the group with occlusion Angle < 30° was shorter than that in the group with occlusion Angle ≥30° (24.50±5.39min VS 39.05±4.31min

t=11.090

P < 0.05)

and the difference was statistically significant. Conclusion There is a positive correlation between the occlusion Angle and the intracardiac operation time in TEE guided transthoracic minimally invasive pmVSD occlusion

and a smaller occlusion Angle < 30° can improve the success rate of the operation and shorten the intracardiac operation time.