Study Limitations
The nature of the data currently available in the published literature
carries its own inherent limitations. Patients with multiple defects and
the Swiss-cheese septum undergoing different types of surgical
procedures, and transcatheter/hybrid closure are small in number, with
incomplete follow-up. This makes it difficult to draw long-term
conclusions at this stage. The numbers of patients reported with the
different anatomical sub-sets, including the Swiss-cheese variety, were
not large enough for analysis to be convincing, although the results are
consistent with the clinical practice. Thus far, furthermore, patients
have not been randomized between surgical, and interventional or hybrid
closure, thus meaning that comparisons between the groups may be biased.
Experienced hands, with highly specialized backup, must be available for
safety. Whereas the long-term safety and efficacy of surgery are well
documented, the long-term results of device closure are unknown. Future
prospectively designed multicentric studies with larger sample sizes
will be needed to substantiate our inferences made on the basis of from
the published literature.