Evaluates the natural history of congenital heart lesions as a background to finding out if and how much treatment has improved outcomesIntroduces and defines lesions, providing general information about its frequency, familial or syndromic associations, and associated congenital heart lesionsProvides sections on pathological anatomy and physiology – important in determining outcomesIncludes results of surgery, both in terms of survival and also in terms of event-free survival, that is, survival free of reoperation, cardiac failure, arrhythmias, and other late complications that are often seenHelps cardiologists and cardiac surgeons understand what is likely to happen to patients with or without treatment, and which forms of treatment currently in use provide the best outcomes to date