| First Author | Fernández B | Year | 2009 |
| Journal | J Am Coll Cardiol | Volume | 54 |
| Issue | 24 | Pages | 2312-8 |
| PubMed ID | 19958967 | Mgi Jnum | J:160039 |
| Mgi Id | MGI:4453291 | Doi | 10.1016/j.jacc.2009.07.044 |
| Citation | Fernandez B, et al. (2009) Bicuspid aortic valves with different spatial orientations of the leaflets are distinct etiological entities. J Am Coll Cardiol 54(24):2312-8 |
| abstractText | OBJECTIVES: The aim of this study was to decide whether bicuspid aortic valves (BAVs) with fused right and noncoronary leaflets (R-N) and BAVs with fused right and left leaflets (R-L) have different etiologies or are the product of a single diathesis. BACKGROUND: The BAV is the most common congenital cardiac malformation. The R-N and R-L BAVs are the most frequent BAV subtypes. METHODS: The study was carried out in adult and embryonic hearts of endothelium nitric oxide synthase knock-out mice and inbred Syrian hamsters with a high incidence of R-N and R-L BAVs, respectively. The techniques used were histochemistry, immunohistochemistry, and scanning electron microscopy. RESULTS: The R-N BAVs result from a defective development of the cardiac outflow tract (OT) endocardial cushions that generates a morphologically anomalous right leaflet. The left leaflet develops normally. The R-L BAVs are the outcome of an extrafusion of the septal and parietal OT ridges that thereby engenders a sole anterior leaflet. The noncoronary leaflet forms normally. CONCLUSIONS: The R-N and R-L BAVs are different etiological entities. The R-N BAVs are the product of a morphogenetic defect that happens before the OT septation and that probably relies on an exacerbated nitric oxide-dependent epithelial-to-mesenchymal transformation. The R-L BAVs result from the anomalous septation of the proximal portion of the OT, likely caused by a distorted behavior of neural crest cells. Care should be taken in further work on BAV genetics because R-N and R-L BAVs might rely on different genotypes. Detailed screening for R-N and R-L BAVs should be performed for a better understanding of the relationships between these BAV morphologic phenotypes and other heart disease. |
