INTRODUCTION
It is 130 years since Fallot described the 4 cardinal features of la maladie bleue [1] namely the complex of pulmonary infundibular stenosis, an interventricular communication, biventricular connection of the aorta and right ventricular hypertrophy. Our understanding of the developmental anomaly, phenotypic features and surgical management has advanced considerably in the intervening years [2–4]. The anterocephalad deviation of the outlet septum, with associated abnormal septoparietal trabeculations, is now accepted as the hallmark of tetralogy [5, 6]. This outlet septal deviation also results in varying degrees of aortic override and can be associated with several types of ventricular septal defect [7].
The combination of lesions can be found with a wide spectrum of associated anomalies, including so-called absent pulmonary valve, pulmonary atresia, atrioventricular septal defect, abnormal branching of the coronary arteries, a right aortic arch and persistence of the left superior caval vein [4, 8, 9]. While some of these structural anomalies may simply be benign variations, others have significant implications for surgical management. Preoperative imaging, therefore, should be focused on variants known to be of significance, such as a coronary artery traversing the right ventricular outflow tract [10]. Advanced knowledge of these factors, and their clinical implications, will inform the discussion with parents regarding prognosis and reintervention and aid planning of the operative repair.
Post-mortem heart specimens stored in historical archives provide a valuable resource for direct examination of the anatomy of such congenital heart defects and their associated anomalies. The transformation of surgical interventions and outcomes over the last 60 years, along with changes in societal attitudes towards post-mortem, highlight the irreplaceability of these collections and their ongoing value for morphological research. The Birmingham Children’s Hospital cardiac archive provides us with the unique opportunity to examine a range of unrepaired and historically operated hearts. Using this archive, we have sought to determine the morphological and geometric features of tetralogy, defining variations such as aortic override, coronary arterial patterns and the morphology of ventricular septal defects which may have implications for surgical management.