This book is written to clarify and demystify the pathophysiology of congenital heart disease, which many find daunting. lt focuses on what is relevant from a surgical point of view, i. e. issues that would be helpful to people involved in perioperative care. This is important, since the functions and processes of the cardiovascular system may be profoundly altered in many forms of congenital heart disease such that the common and well-known protocols of clinical care may not apply, or even do harm. A sound understanding of this pathophysiology would enable clinicians to make decisions tailored to the needs of each patient, anticipate problems and adjust to them, or even formulate individualized treatment strategies from first principles. About the revised edition

Although this book was published very recently. it required an urgent revision because the definition of pulmonary hypertension, having been the same for several decades, was changed while this book was being published. This issue could not be ignored given the importance of pulmonary hypertension in the context of congenital heart disease. Therefore, this revised edition was published with up-to-date information. This also gave me the opportunity to add more detail for further clarification of sorne of the more challenging concepts.