Has the Congenitally Malformed Heart Changed Its Face?
Journey From Understanding Morphology to Surgical Cure in Congenital Heart Disease
The incidence of children born with congenitally malformed hearts has changed little over the centuries. Our understanding of the lesions has improved subsequent to analysis in sequential fashion of the cardiac components. Ongoing differences in the approach to naming the lesions can now be resolved by careful application of the new evidence emerging from examination of the developing heart and by noting the lesions produced by genetic manipulation of mice.
The recorded incidence of congenital cardiac malformations has changed little across the ages. At a rough estimate, ≈8 infants in every 1000 are born with a congenitally malformed heart, with little difference being found in this number across the World. The lesions themselves have been recognized for centuries. In 1846, for example, Thomas Peacock described a deficiency of the base of the interauricular septum in the heart removed from a patient having a distinctly tricuspid form of the left auriculoventricular valve.1 It has taken 170 years to re-establish the fact that the left atrioventricular valve in the ostium primum defect is trifoliate, rather than representing a cleft mitral valve. Examples of the lesion we now recognize as tetralogy of Fallot were illustrated well before the description provided by Fallot himself, not least in the atlas of Von Rokitansky.2 In his own description, nonetheless, Fallot provided the evidence that should have forestalled another ongoing controversy, namely the association between tetralogy and double-outlet right ventricle, when he described that, in one of the hearts obtained from a patient with la maladie bleue, the aortic valve was supported exclusively by the right ventricle.3 Examination of the atlases of Von Rokitansky2 and Maude Abbott,4 furthermore, provides illustrations of the phenotypic features of most of the lesions that we now recognize as constituting congenital cardiac disease. The lesions themselves, therefore, …