title: Beating-heart patch closure of muscular ventricular septal defects under real-time three-dimensional echocardiographic guidance: a preclinical study.
abstract: OBJECTIVE
  Safe and effective device closure of ventricular septal defects remains a challenge. We have developed a transcardiac approach to close ventricular septal defects using a patch delivery and fixation system that can be secured under real-time three-dimensional echocardiographic guidance.
  
  
  METHODS
  In Yorkshire pigs (n = 8) a coring device was introduced into the left ventricle through a purse-string suture placed on the left ventricular apex, and a muscular ventricular septal defect was created. The patch deployment device containing a 20-mm polyester patch was advanced toward the ventricular septal defect through another purse-string suture on the left ventricular apex, and the patch was deployed under real-time three-dimensional echocardiographic guidance. The anchor delivery device was then introduced into the left ventricle through the first purse-string suture. Nitinol anchors to attach the patch around the ventricular septal defect were deployed under real-time three-dimensional echocardiographic guidance. After patch attachment, residual shunts were sought by means of two-dimensional and three-dimensional color Doppler echocardiography. The heart was then excised, and the septum with the patch was inspected.
  
  
  RESULTS
  A ventricular septal defect was created in the midventricular (n = 4), anterior (n = 2), and apical (n = 2) septum. The mean size was 9.8 mm (8.2-12.0 mm), as determined by means of two-dimensional color Doppler scanning. The ventricular septal defects were completely closed in 7 animals. In one a 2.4-mm residual shunt was identified. No anatomic structures were compromised.
  
  
  CONCLUSIONS
  Beating-heart perventricular muscular ventricular septal defect closure without cardiopulmonary bypass can be successfully achieved by using a catheter-based patch delivery and fixation system under real-time three-dimensional echocardiographic guidance. This approach might be a better alternative to cardiac surgery or transcatheter device closure.
authors.affiliation: Department of Cardiac Surgery, Children's Hospital Boston, Harvard Medical School, Boston, Mass 02115, USA.
authors.forename: Nikolay V
authors.initials: NV
authors.lastname: Vasilyev
authors.forename: Ivan
authors.initials: I
authors.lastname: Melnychenko
authors.forename: Kazuo
authors.initials: K
authors.lastname: Kitahori
authors.forename: Franz P
authors.initials: FP
authors.lastname: Freudenthal
authors.forename: Alistair
authors.initials: A
authors.lastname: Phillips
authors.forename: Rainer
authors.initials: R
authors.lastname: Kozlik-Feldmann
authors.forename: Ivan S
authors.initials: IS
authors.lastname: Salgo
authors.forename: Pedro J
authors.initials: PJ
authors.lastname: del Nido
authors.forename: Emile A
authors.initials: EA
authors.lastname: Bacha
mesh_terms: D000818:Animals; D006328:Cardiac Catheterization / Q000379:methods; D006348:Cardiac Surgical Procedures / Q000379:methods*; D002315:Cardiopulmonary Bypass / Q000379:methods; D004195:Disease Models, Animal; D018618:Echocardiography, Doppler, Color; D019560:Echocardiography, Three-Dimensional; D006344:Heart Septal Defects, Atrial / Q000000981:diagnostic imaging* / Q000601:surgery*; D019060:Minimally Invasive Surgical Procedures / Q000379:methods; D019736:Prostheses and Implants; D019919:Prosthesis Implantation / Q000379:methods; D011897:Random Allocation; D012680:Sensitivity and Specificity; D013552:Swine; D018084:Ultrasonography, Interventional