Unbalanced atrioventricular septal defect with dominant right ventricle: diagnostic criteria, indications for biventricular correction, and results. A clinical observation series

Relevance: Surgical treatment for congenital heart disease (CHD) with borderline left ventricle (LV) dimensions is one of the most challenging issues in current pediatric cardiac surgery. Despite the prevailing general trend to the expansion of indications for biventricular repair of an unbalanced atrioventricular septal defect (AVSD) with a dominant right ventricle (RV), the diagnostic criteria for imbalance, feasibility of radical repair and its functional results are intensively discussed in the literature.Aim: To present quantitative criteria for the assessment of the LV size which could serve as an indication for biventricular repair of the right dominant unbalanced AVSD.Materials and methods: We present a series of 4 patients with AVSD and dominant RV, who underwent radical repair of the defect. The mean age of the patients was 2.4 years, and 3 of 4 had concomitant CHD: tetralogy of Fallot, double outlet right ventricle with pulmonary artery stenosis, and moderate hypoplasia of the aortic arch with subaortic stenosis. Three of 4 patients had previously undergone palliative interventions: two of them – pulmonary bending, one, the first stage of univentricular repair (atrioseptostomy, cavopulmonary anastomosis). Two children had been diagnosed with Down syndrome. The mean left ventricular end diastolic diameter (LVEDD) at baseline was 17.9 mm, corresponding to Z score of -5.4.Results: All four patients underwent biventricular repair of the defect with a two-patch technique. In one case, it was supplemented with placement of the pulmonary trunk homograft prosthesis, in the other with pulmonary valve commissurotomy and cavopulmonary anastomosis due to moderate tricuspid valve stenosis and in the third case the mitral valve was replaced. In 3 patients pacemaker implantation was performed. The criterion for feasibility of complete septation was the ratio of the longitudinal dimensions of the left and right ventricles (LAR > 0.7), confirmed by computed tomography performed before the surgery. The mean LVEDD after surgery was 28.3 mm, corresponding to Z score of -0.8. At the time of the hospital discharge, the left and right atrioventricular valves insufficiency did not exceed 2 and 1 degrees, respectively.Conclusion: Computed tomography allows for accurate measurement and comparison of the longitudinal dimensions of the heart ventricles with LAR index as a tool for assessment of the LV size before the biventricular repair. An additional prospective study is required to objectify the data obtained and identify predictors of an unfavorable outcome of radical repair in patients with right dominant unbalanced AVSD.

Infant Ross-Konno, Endocardial Fibroelastosis Resection and Mitral Valve Repair

Optimal management of critical aortic stenosis (AS) in infants depends on the left ventricle's (LV's) ability to maintain adequate output. Determining feasibility of biventricular repair may be difficult, particularly in those with mitral disease, endocardial fibroelastosis (EFE), multi-level obstruction, and uncertain physiologic capacity. We report a case of a three-month-old with critical AS, severely reduced LV function, EFE, and moderate mitral regurgitation (MR), who underwent a Ross-Konno procedure with concomitant EFE resection and mitral valve repair. Although the technical sequence is challenging, definitive surgery completely relieved multi-level obstruction and MR with markedly improved LV function.

Enhanced 3D visualization for planning biventricular repair of double outlet right ventricle: a pilot study on the advantages of virtual reality

Aims We aim to determine any additional benefit of virtual reality (VR) experience if compared to conventional cross-sectional imaging and standard 3D modelling when deciding on surgical strategy in patients with complex double outlet right ventricle (DORV). Methods and results We retrospectively selected ten consecutive patients with DORV and complex interventricular communications, who underwent biventricular repair. An arterial switch operation (ASO) was part of the repair in three of those. CT or cardiac MRI images were used to reconstruct patient-specific 3D anatomies, which were then presented using different visualisation modalities: 3D pdf, 3D printed models, and VR models. Two experienced paediatric cardiac surgeons, blinded to repair performed, reviewed each case evaluating the suitability of repair following assessment of each visualization modalities. In addition, they had to identify those who had ASO as part of the procedure. Answers of the two surgeons were compared to the actual operations performed. There was no mortality during the follow-up (mean = 2.5 years). Two patients required reoperations. After review of CT/CMR images, the evaluators identified the surgical strategy in accordance with the actual surgical plan in 75% of the cases. When using 3D pdf this reached only 70%. Accordance improved to 85% after revision of 3D printed models and to 95% after VR. Use of 3D printed models and VR facilitated the identification of patients who required ASO. Conclusion VR can enhance understanding of suitability for biventricular repair in patients with complex DORV if compared to cross-sectional images and other 3D modelling techniques.

Technical Features of Biventricular Repair for Unbalanced Transitional AVSD With LVOTO

Surgical management of left ventricle outflow tract obstruction in infants with right-dominant unbalanced transitional atrioventricular septal defect poses difficulties. A two-month-old infant with transitional atrioventricular septal defect and complex left ventricle outflow tract obstruction presented in cardiogenic shock. The patient underwent successful biventricular repair. The operative procedure included detachment of the anterior bridging leaflet and resection of its chordal attachments. Septal myectomy was performed with creation of an interventricular communication, followed by patch augmentation of the left ventricular outflow tract and anterior bridging leaflet. The zone of apposition between anterior and posterior bridging leaflets was closed. The repair resulted in effective augmentation of the left ventricular inflow and outflow tracts.

Critical Ebstein’s anomaly with circular shunt: from successful fetal therapy with non-steroidal anti-inflammatory drugs to biventricular repair using Da Silva cone technique

We report an innovative treatment strategy for fetal Ebstein’s anomaly with a circular shunt. We used transplacental non-steroidal anti-inflammatory drugs, at the 29th gestational week, to constrict the ductus arteriosus avoiding fetal demise. We addressed the critical neonate with an urgent Starnes procedure. Finally, instead of following the usual single-ventricle palliation pathway after the Starnes procedure, we achieved successful two-ventricle repair with the cone technique at 5 month old.

Can Left Atrioventricular Valve Reduction Index (LAVRI) Predict the Surgical Strategy for Repair of Atrioventricular Septal Defect?

Despite improved survival, surgical treatment of atrioventricular septal defect (AVSD) remains challenging. The optimal technique for primary left atrioventricular valve (LAVV) repair and prediction of suitability for biventricular approach in unbalanced AVSD are still controversial. We evaluated the ability of our recently developed echocardiographic left atrioventricular valve reduction index (LAVRI) in predicting LAVV reoperation rate and surgical strategy for unbalanced AVSD. Retrospective echocardiographic analysis was available in 352 of 790 patients with AVSD treated in our institution and included modified atrioventricular valve index (mAVVI), ventricular cavity ratio (VCR), and right ventricle/left ventricle (RV/LV) inflow angle. LAVRI estimates LAVV area after complete cleft closure and was analyzed with regard to surgical strategy in primary LAVV repair and unbalanced AVSD. Of the entire cohort, 284/352 (80.68%) patients underwent biventricular repair and 68/352 (19.31%) patients underwent univentricular palliation. LAVV reoperation was performed in 25/284 (8.80%) patients after surgical correction of AVSD. LAVRI was significantly lower in patients requiring LAVV reoperation (1.92 cm2/m2 [IQR 1.31] vs. 2.89 cm2/m2 [IQR 1.37], p = 0.002) and significantly differed between patients receiving complete and no/partial cleft closure (2.89 cm2/m2 [IQR 1.35] vs. 2.07 cm2/m2 [IQR 1.69]; p = 0.002). Of 82 patients diagnosed with unbalanced AVSD, 14 were suitable for biventricular repair (17.07%). mAVVI, LAVRI, VCR, and RV/LV inflow angle accurately distinguished between balanced and unbalanced AVSD and predicted surgical strategy (all p < 0.001). LAVRI may predict surgical strategy in primary LAVV repair, LAVV reoperation risk, and suitability for biventricular approach in unbalanced AVSD anatomy.

Left heart growth and biventricular repair after hybrid palliation

OBJECTIVES We evaluated the outcomes of biventricular repair after initial hybrid palliation performed in small infants with various forms of left ventricle hypoplasia. METHODS Between September 2010 and January 2020, a total of 27 patients had biventricular repair after hybrid palliation at a median age of 11 days. Indications for the hybrid approach included growth promotion of the left ventricle outflow tract and/or the aortic valve in 14 patients and that of the left ventricle in 13 patients. Seven reinterventions and 7 reoperations were performed during the interstage period. Significant growth of left ventricle parameters was noted during the median interstage period of 62 days. Sixteen subjects had aortic arch repair, ventricular septal defect closure and relief of subaortic stenosis; 5 patients had the Ross–Konno procedure; 5 patients underwent the Yasui procedure; and 1 patient had unbalanced atrioventricular septal defect and aortic arch repair. RESULTS Twenty-three patients (85.2%) are alive at a median follow-up of 3.3 years. Two and 3 patients died early and late after achieving biventricular circulation, respectively. There were 22 reinterventions and 15 reoperations after biventricular repair. CONCLUSIONS Hybrid palliation can stimulate left heart growth in some patients with left ventricle hypoplasia. More patients may eventually achieve biventricular circulation than was initially thought. Additional interventions and operations are foreseeable. Despite ventricular rehabilitation, some patients with borderline left ventricles may develop restrictive physiology.