Johns Hopkins has been a leader in paediatric cardiology for over 85 years. In the 1940s, Dr Helen Taussig began training fellows in paediatric cardiology at Johns Hopkins at a time when the diagnosis and treatment of CHD were in the earliest stage. Under her leadership, the fellowship developed a strong foundation that has continued to evolve to meet the current needs of learners and educators. In the current era, the Johns Hopkins programme implements the current theories of adult education and actively engages our fellows in learning as well as teaching. The programme uses techniques such as flipped classroom, structured case-based small-group learning, observed and structured clinical examination, simulations, and innovative educational technology. These strategies combined with our faculty and rich history give our fellows a unique educational experience.

Decades ago, mass-scale epidemiologic studies were undertaken to accurately describe the prevalence of congenital heart disease and associated malformations, and to identify inheritance patterns, teratogenic influence and aetiologic underpinnings. Despite phenomenal breakthroughs in molecular diagnosis of congenital heart disease, original population-based studies for detailed knowledge of prevalence, associated malformations, and appropriate patient and family counselling remain invaluable to the armamentarium and knowledge base of paediatric cardiologists. No modern-era studies have supplanted the importance of the Baltimore-Washington Infant Study undertaken from 1981 to 1989. In this article, we reprise the findings of the Baltimore-Washington Infant Study in tetralogy of Fallot, as well as to review current molecular diagnosis.

Congenital cardiac disease is the most common birth defect, occurring in approximately 1 in 1000 live births. Congenital cardiac defects have associations, whether with gender, race, or specific chromosomal abnormalities, potentially allowing grouping of defects to be studied in an effort to develop an understanding of aetiological factors. The Baltimore-Washington Infant Study provides full ascertainment of a population of infants with congenital cardiac disease born in a defined geographic region. The fundamental hypotheses generated at the inception of the Baltimore-Washington Infant Study included the central idea that the outcome of birth, including the development of congenital cardiac malformations, was influenced by environmental factors and their route of introduction into a genetically susceptible host. Evidence exists that supports the concept that both genetic and environmental factors contribute to the development of diseases of the left heart.

Cognitive, functional, educational achievement and behavioural measures were employed to assess neurobehavioral status in 57 of 60 participants who were initially enrolled in the Baltimore–Washington Infant Study, and who survived surgical correction of complete transposition (concordant atrioventricular and discordant ventriculo-arterial connections). Charts were reviewed to investigate the relationship between birth variables, surgical strategy and developmental outcomes. Higher preoperative weight was associated with better outcomes on the Stanford–Biner Short-term Memory subtest, while lower preoperative oxygen tension was associated with better outcomes on the Abstract/Visual Reasoning subtest and a test of Visual–Motor Integration. Longer total bypass time was associated with poor outcomes on the Short-term Memory subtests. Higher average flow rates during cooling and rewarming were associated with higher scores in the test of short term memory but poorer outcomes on a test for visual motor integration. Longer cooling times were associated with higher scores on the test for Visual–Motor Integration. Patients suffering seizures scored lower on the Stanford–Biner Composite, as well as in their tests of achievement. The data indicate that non-verbal. skills may be particularly sensitive to variations in surgical strategies employed to correct complete transposition. Overt neurological events, such as seizures, were related to global deficits in intellectual functioning. Prospective studies evaluating systemic variations in surgical procedures and attempts to prevent and manage perioperative neurological events are important for further investigation of neurodevelopmental outcomes in children surviving surgical correction.