Echocardiographic Definition and Surgical Decision-Making in Unbalanced Atrioventricular Septal Defect A Congenital Heart Surgeons' Society Multiinstitutional Study

Labatt Family Heart Centre, The Hospital for Sick Children, Toronto, ON, Canada.
Circulation (Impact Factor: 14.43). 09/2010; 122(11 Suppl):S209-15. DOI: 10.1161/CIRCULATIONAHA.109.925636
Source: PubMed


Although identification of unbalanced atrioventricular septal defect (AVSD) is obvious when extreme, exact criteria to define the limits of unbalanced are not available. We sought to validate an atrioventricular valve index (AVVI) (left atrioventricular valve area/total atrioventricular valve area, centimeters squared) as a discriminator of balanced and unbalanced forms of complete AVSD and to characterize the association of AVVI with surgical strategies and outcomes.
Diagnostic echocardiograms and hospital records of 356 infants with complete AVSD at 4 Congenital Heart Surgeons' Society (CHSS) institutions (2000-2006) were reviewed and AVVI measured (n=315). Patients were classified as unbalanced if AVVI≤0.4 (right dominant) or ≥0.6 (left dominant). Surgical strategy and outcomes were examined across the range of AVVI. Competing risks analysis until the time of commitment to a surgical strategy examined 4 end states: biventricular repair (BVR), univentricular repair (UVR), pulmonary artery banding (PAB), and death before surgery. A prediction nomogram for surgical strategy based on AVVI was developed. The majority of patients had balanced AVSD (0.4<AVVI<0.6) and underwent BVR. Patients with AVVI<0.19 uniformly underwent UVR. Heterogeneous repair strategies were found when 0.19≤AVVI≤0.39 (UVR and BVR), with a disproportionate number of deaths in this range. AVVI≥0.6 (left dominant) was less common. The proportion of subjects predicted for the end states at 12 months after diagnosis are: BVR, 86%; UVR, 7%; PAB, 1%; death without surgery, 1%; alive without surgery, 5%.
AVVI effectively characterizes the transition between balanced and unbalanced AVSD with important correlation to anatomic substrate and selected surgical strategy.

Download full-text


Available from: Meryl S Cohen, Aug 08, 2015
  • [Show abstract] [Hide abstract]
    ABSTRACT: Congenital mitral and tricuspid valve abnormalities in unbalanced atrioventricular canal defects are complex. We designed procedures to both repair and induce growth of hypoplastic atrioventricular valves and ventricles to achieve 2-ventricle repairs. Midterm data were assessed for reliability of catch-up growth, resulting quality of atrioventricular valves, and adequacy of 2-ventricle repairs. The 24 consecutive infants (14 female and 10 male) with unbalanced atrioventricular canal defects had significant hypoplasia of 1 atrioventricular valve and/or ventricle (an echocardiography-derived z value of ≤-3.0 standard errors of the mean below expected). Operative approaches included the following: (1) Staged repair was performed, with complete valve repair, partial closure of the atrial septal, and ventricular septal defects, and (usually) pulmonary artery banding. After adequate growth, repair was completed. A vestigial mitral valve (4-7 mm) in 3 patients led to partitioning the large tricuspid valve, creating a second mitral valve. (2) Repair with a shift in atrioventricular valve partitioning was performed to increase hypoplastic atrioventricular valve size. (3) Repair with snared atrial septal defects and ventricular septal defect was performed to allow intracardiac shunting. The hypoplastic atrioventricular valves and hypoplastic ventricles were reassessed on local follow-up (5-15 years). The initial z scores were -2.8 to -7.4 for hypoplastic atrioventricular valves and -1.0 to -7.5 for hypoplastic ventricles. Follow-up z scores were -0.6 to -2.7 for hypoplastic atrioventricular valves and -2.0 to +1.8 for hypoplastic ventricles. Another 11 patients were also judged to be within normal limits. Three reoperations were for mitral valve regurgitation, and 1 reoperation was for mitral valve replacement. One patient died of central nervous system bleed just before extracorporeal membrane oxygenation weaning, and 2 patients died of late potassium overdose, for an 88% survival. Survivors are well with 2-ventricle repairs, and 15 of 19 patients are not taking cardiac medications. Increasing atrioventricular valve flow reliably induced growth. Valve repair and growth achieved a 2-ventricle repair in all patients.
    No preview · Article · Dec 2011 · The Journal of thoracic and cardiovascular surgery
  • [Show abstract] [Hide abstract]
    ABSTRACT: We report a rare case of a neonate with interrupted aortic arch, aortopulmonary window and complete atrioventricular septal defect. To the best of our knowledge, this unusual triad has not been previously described. The main question of the surgical strategy for CAVSD, in setting of associated defects, is to classify the CAVSD as balanced or unbalanced.
    No preview · Article · Feb 2012 · Indian pediatrics
  • [Show abstract] [Hide abstract]
    ABSTRACT: Malformations of the cardiac septum associated with intracardiac shunting constitute the most common group of congenital heart defects in the human population. They can be isolated or exist as a part of more complex cardiovascular anomalies. Importance of septal defects implicates a need for precise description of anatomy and embryogenesis of interatrial, atrioventricular and interventricular septums in a way useful for diagnosis and therapy. This paper presents morphology of the cardiac septum consistent with current international bibliography. True atrial septal defects are separated from other forms of interatrial communication. Common features of all atrioventricular septal defects are described. Morphological criteria independent on numerous existing classifications are presented as a base for accurate description of ventricular septal defects. In the era of rapidly developing prenatal cardiology, paediatric cardiology and cardiac surgery implicating effective treatment of intracardiac shunts, the knowledge about anatomy of cardiac septal malformations is crucial for specialist in various fields of medicine. Unified communication code assures appropriate cooperation of physicians involved in treatment of patients in every period of their life.
    No preview · Article · Mar 2012 · Pediatria polska
Show more