Methods
We searched the extant literature for the described instances of the management of multiple ventricular septal defects. We then collated the demographics, the anatomical details encountered, the indications for surgery or intervention, and outcomes of management, including reinterventions. The search engines employed were PubMed, Google Scholar, Cochrane Database for Systematic Reviews, Cochrane Central Register of Controlled Trials, Ovid Medline, ACP Journal Club, Ovid EMBASE, and Database of Abstracts of Review of Effectiveness in all languages.
Analysis was based initially on the individualized review of the initial 77 investigations. These were then incorporated, as far as possible, with the results and recommendations from the Congenital Heart Surgery Database as provided by the Society of Thoracic Surgeons. The society has collated the findings from 116 participating centers. We also took note of the scientific statement of the American Heart Association, endorsed by the American Academy of Pediatrics and the Society for Cardiovascular Angiography and Intervention.29-32 So as to unify the divergent approaches to the description and categorization of ventricular septal defects, we assessed the reports, as far as was possible, on the basis of the categorization proposed for the Eleventh Iteration of the International Classification of Disease, as produced by the International Society for Nomenclature of Pediatric and Congenital Heart Diseases.33,34
Due to the limited sizes of the descriptive case series reported, and the heterogeneity of clinical states at the time of surgical intervention, along with the difficulties in selection of appropriate cardiac quantifiable end points, we are unable to perform a meta-analysis. Our analysis therefore, is based on review of case reports, and small case series, along with incorporation of data from the extensive series published by the Society of Thoracic Surgeons Registry, the scientific statement of the American Heart Association, and the report from the International Society for Nomenclature of Pediatric and Congenital Heart Diseases.28-34