Diane E. Spicer

and 7 more

Over the course of time, new developments associated with embryogenesis of the murine heart have served to clarify the developmental processes observed in the human heart. This evidence allows for creation of a developmental framework for many congenital cardiac defects. Here, we aim to solidify the framework related to the categorization of both solitary and multiple ventricular septal defects. Mice having genetic perturbation of the Furin enzyme have demonstrated perimembranous and juxta-arterial ventricular septal defects, permitting the inference to be made that these defects can co-exist with defects occurring within the apical muscular septum. Based on developmental evidence, furthermore, all interventricular communications can be placed into one of three groups, namely, those which are perimembranous, juxta-arterial, and muscular. All of the defects are described based on their borders as seen from the morphologically right ventricle. Our focus here will be on those defects within the muscular ventricular septum, recognizing that such defects can co-exist with those that are perimembranous. We discuss the differentiation of multiple discrete defects from those referred to as the ‘Swiss cheese’ variant. As we show, appropriate surgical management requires understanding of the specific terminology, as the surgical approach may differ depending on the combination of the individual defects. Data from the Society for Thoracic Surgeons revealed that both mortality and morbidity were increased in the setting of multiple as opposed to solitary ventricular septal defects.

Ujjwal Chowdhury

and 8 more

Background and Aim: We showed in our anatomical review, ventricular septal defects existing as multiple entities can be considered in terms of three major subsets. We address here the diagnostic challenges, associated anomalies, the role and techniques of surgical instead of interventional closure, and the outcomes. including reinterventions, for each subset. Methods: We reviewed 80 published investigations, noting radiographic findings, and the results of clinical imaging elucidating the location, number, size of septal defects, and associated anomalies, and the effect of severe pulmonary hypertension. Results: Overall, perioperative mortality for treatment of residual multiple defects has been cited to be between zero and 14.2%, with morbidity estimated between 6% to 13%. Perioperative mortality is twice as high for perimembranous compared to muscular defects, with need for reoperation is over four times higher. Perventricular hybrid approaches are useful for closure of high anterior or apical defects. Overall, results have been unsatisfactory. Pooled data reveals incidences between 2.8% and 45% for device-related adverse events. Currently, however, outcomes cannot be assessed on the basis of the different anatomical sub-sets. Conclusions: We have addressed the approaches, and the results, of therapeutic treatment in terms of co-existing discrete defects, the Swiss-cheese septum, and the arrangement in which a solitary apical muscular defect gives the impression of multiple defects when viewed from the right ventricular aspect. Treatment should vary according to the specific combination of defects.