The purpose of this study is to investigate the security and validity of transesophageal echocardiography(TEE)-guided perventricular device closure(TPDC) through minithoracotomy in treatment of infundibular ventricular septal defect(IVSD) with asymmetric occluder.

Ventricular septal defect(VSD) , which accounted for about 20% of all congenital heart defects (CHDs) , is among the most common congenital heart malformations，among which infundibular ventricular septal defects(IVSD) is the least common type(18%）.Multiple names for IVSD are in use. They can also be labeled conal VSD, subpulmonary VSD, subarterial VSD, doubly committed VSD, intracristal VSD，or supracristal VSD. These multiple denominations are not attached to specifically different anatomic subtypes.At present, the main methods to treat the specific anatomic condition contain conventional surgical repair(SR) and transcatheter interventional closure. The former need extracorporeal circulation，thus the side effects of extracorporeal circulation are inevitable，such as on the central nervous system, respiratory system, urinary system, etc. Although the latter has the characteristics of minimally invasive, patients should be exposed in X-ray withstanding potential risk of radiation. On the other hand，there are limits with age for patients who underwent transcatheter closure because of small vessel size. Fully developed blood vessels are to reach a certain diameter, but children need be up to 3 years old or so. In addition,the aortic valve was easily injured by wire and atrioventricular block was reported.Since the surrounding structure is complicated and the defect is too high, device closure of an IVSD is difficult to succeed in transcatheter approach. Traditional repair via cardiopulmonary bypass(CBP) is widely used to treat this kind of diseases. Past decade，with the development of technology and society，TEE-guided surgical occlusion through minithoracotomy was used to treat CHDs in an increasing number of popularity，avoiding the inherent risks of cardiopulmonary bypass and radiation,etc. But it is rarely reported to treat IVSD by minimally invasive perventricular device closure without CBP.

Inclusion Criteria:

(1) patients with single IVSD indicated by TTE，without concomitant cardiac malformation, serious arrhythmia or other important non-cardiac diseases；(2) patients whose ventricular septal defects from aortic residual < 3 mm, preoperative without aortic regurgitation or only mild reflux, defect size ≤10 mm;

Exclusion Criteria:

(1) defect size > 10 mm in diameter; （2) Preoperative with above moderate aortic valve prolapse (or) closed incompletely; (3) Eisenmenger syndrome caused by pulmonary hypertension,(4)decide temporarily to change method before surgery;(5) not signed informed consent application