Congenital heart diseases occur with a frequency of 0.5 to 1 case per 1000 live births, accounting for more than 50% of reported birth defects. In addition, they are the leading cause of infant mortality in the first year of life. Significant progress in the diagnosis and treatment of most defects has been made in the past few years. In addition, new experimental evidence suggests that we soon may be able to identify the genes involved in disturbed cardiac anatomy and function. The following is a brief overview of some of the more recent developments that have made an important impact on the contemporary management of the child who has congenital heart disease. Transcatheter Ablation of Pediatric Tachyarrhythmias: A Cure Without Medication The prevalence of tachyarrhythmias within the general pediatric population is such that virtually every practitioner is faced with diagnostic and management considerations that involve patients from birth through adolescence. Fortunately, most tachyarrhythmias can be managed with relatively benign pharmacologic therapies. However, there is a subset of patients who do not respond to "simple" medical intervention, requiring multiple or more potent antiarrhythmic medications that may involve frequent or prolonged hospitalizations for monitoring and optimization of therapeutic regimens. These medications also may cause significant side effects and often result only in a decrease, not elimination, of the arrhythmia.