Ana De Dios

Feasibility of Biventricular Repair in Right Dominant Unbalanced Atrioventricular Septal Defect: A New Echocardiographic Metric to Refine Surgical Decision-Making

Background: Unbalanced forms of atrioventricular septal defect continue to be challenging and present poor surgical outcomes. Echocardiographic indicators such as atrioventricular valve index, right ventricle/left ventricle inflow angle, and size of the ventricular septal defect have been identified as relevant discriminators that may guide surgical strategy. Our purpose is to describe another metric to refine surgical decision-making. Methods: We outline a geometrical description of the anatomic features of atrioventricular septal defect and describe equations that help explain the interplay between the main echocardiographic variables. Results: A new metric called “indexed ventricular septal defect” is defined as the size of the defect in relation to the valve diameter. We derive a final equation relating this index with the atrioventricular valve index and the right ventricle/left ventricle inflow angle. In the light of that equation, we discuss the interdependence of variables and employ data from a Congenital Heart Surgeons’ Society study to set the limits of the new index. Conclusion: Combined use of indexed ventricular septal defect and atrioventricular valve index might help clarify surgical decision-making in patients with mild and moderate unbalance (modified atrioventricular valve index between 0.2 and 0.39). For indexed ventricular septal defect smaller than 0.2, biventricular repair may be recommended. Between 0.2 and 0.35, this strategy could probably be achieved depending on other factors. However, other strategies should be considered for those patients showing an indexed ventricular septal defect between 0.35 and 0.5. For values above 0.5 to 0.55, univentricular palliation might be a reasonable strategy.

Preoperative management of congestive heart failure in neonates: the closed hood

In this study we report the results of the use of a closed hood with no external administration of CO2 to increase pulmonary vascular resistance by lowering the inspired fraction of oxygen (FiO2) and raising the inspired fraction of carbon dioxide (FiCO2) in patients with congenital heart disease and increased pulmonary blood flow. Between December 1995 and May 1996, 9 neonates (F:5, M:4) were admitted. Each study patient was assigned to clinical classes using a 1 to 4 classification. Ages ranged between 2 and 30 days (mean 18), weight between 2.25 and 3.65 kg (mean 2.89). A plastic hood, closed on the top with a plastic membrane and with the gas entrance open to room air was placed over the head of the patients. Patients increase pCO2 by rebreathing their own expired CO2. After 24 h of the onset of the treatment the media of points of congestive heart failure 1 to 4 classification decrease from a mean of 4 to a mean of 2.28+/-0.44 (p=0.001). A statistically significant improvement in symptoms and lowering of PO2 and pH while raising pCO2 has been demonstrated in this study.

Modified In Situ Pericardial Rerouting Technique for Scimitar Syndrome Repair

Scimitar syndrome repair represents a challenge due to the high incidence of postoperative pulmonary venous obstruction associated with classic surgical strategies. In situ pericardial rerouting technique has been considered a promising alternative approach due to its simplicity and excellent midterm results. Access to the left atrium can be difficult in young patients with severe dextrocardia and hypoplastic right lung. We describe a modification of the original rerouting technique in which the atrial septum is repositioned in order to create a wide opening in the lateral aspect of the left atrium and ensure an adequate size of the reconstructed pathway.