OBJECTIVE:To investigate the feasibility,safety and efficacy of domestic small waist big edge-type occluder for patients with multiple outlets sac-type membranous ventricular septal defection (VSD),and summarize its technical problems and the choice of treatment strategies.METHODS:A total of 20 patients with sac-type membranous VSD,underwent left ventricular angiography at left anterior oblique 45°-60° plus CAOD 20°-25°;the left ventricular entrance diameters were 7-21 (10.9±5.2) mm,more than 2 outlets in the right ventricular surfaces,and the largest outlet diameters were 3-10 (4.8±2.9) mm.According to the result from transthoracic echocardiography (TTE) and angiography,the sac-bag size,shape,location,extent of tissue adhesion,and stability were determined.Different types of small waist big edge-type occluder were implanted,and the occluder diameter was 5-14 (4.6±2.8) mm.Following 15 minutes of blocking,the immediate effects of occlusion were observed through repeating left ventricuiar angiography and TTE.All patients rechecked ultrasonic cardiography and electrocardiogram at 5-7 days of hospital stay,and 1,3,6 and 12 months following surgery.All patients took aspirin tablets for 6 months.RESULTS:Of 20 patients,17 cases underwent domestic small waist big edge occluder,blocked successfully through left ventricular entrance,2 cases were successful using symmetry block,and 1 case was failed.Intraoperative occlusion did not affect the aortic valve and tricuspid valve function.There were 1 case with left bundle branch block and 1 case with right bundle branch block during the operation,and all recovered within a week by using hormone therapy.After 6 months,the cardiac sizes were reduced to different degrees.CONCLUSION:It is safe and effective to treat multiple outlets sac-shaped membranous VSD with domestic small waist big edge-type occluder.The key technology,according to the sac size,shape,firmness,outlet orientation,import size,and the size of aortic stump,is to determine the block site and to select a suitable occluder.