A clinical relevance of fossa ovalis and patent foramen ovale: A morphological study of human heart

Background: The anatomical characterization of foramen ovale (FO) along with annulus or limbus varies in size and shape from the heart to heart. Patent FO (PFO) has been implicated in the etiology of a number of diseases, PFO is not an uncommon condition; their prevalence rate is 15%–35% in the population. Hence, morphological study of FO serves importance to know the exact location of the fossa ovalis (FOv) and prevalence of PFO in the Indian population by the autopsy method. Materials and Methods: This study was conducted in 106 apparently normal hearts available in the Department of Anatomy and Forensic Medicine and Toxicology. After opening the right atrium, the shape of FOv was observed, and dimensions were measured with the digital Vernier caliper and thickness of anterior and posterior limbus was noted. Probe patency was confirmed. Results: Area of the FOv (160.20 ± 104.9 mm2), thickness anterior limbus (7.24 ± 1.83 mm), and thickness of posterior limbus (6.38 ± 2.46 mm). The shape of FOv was oval (83%) in majority; in 86.7%, the rim of the limbus was raised and 13.3% it was flat; in 20.75%, a recess was found deep to the margin of the limbus and 10.37% showed probe patency. A significant positive correlation was observed between cardiac weight and area of FOv. Conclusion: By autopsy method, we found the prevalence of PFO is 4.71%, which is lower than Western population, our study also provides the accurate measurements related with several morphometric variation such as shape of FOv and limbus FOv.