During the 8 years since the publication of the first edition of Neonatal Cardiology in 2002, many remarkable advances in our understanding of normal cardiovascular development and of mechanisms, resulting in congenital cardiovascular malformations, have been achieved.
The concept that these malformations had little impact on normal fetal development was widely accepted; the influence of congenital cardiovascular malformations on fetal blood flow patterns and oxygenation, as well as their effect on fetal cardiac and vascular development, is increasingly being recognized. Furthermore, the potential effects of these defects on other organ systems, particularly the brain, has engendered great interest and study.
In this second edition, Drs. Michael Artman, Lynn Mahony, and David Teitel have continued the general philosophy of the first edition; they have presented clinical and hemodynamic manifestations of congenital and acquired cardiovascular disturbances, based on biological information regarding development and function. All chapters have been significantly modified to address the increased understanding of basic biology and factors affecting normal development and performance. As in the first edition, the graphic material largely presents diagrams that help to explain basic physiological concepts and pathophysiology. The quality of the diagrams has been greatly improved, making the information presented more readily assimilable.
The first chapter, on cardiac embryology, contributed by Dr. Kathleen Ruppel, reviews the advances in the understanding of genetic pathways involved in cardiac morphogenesis. Also, the revolutionary changes in our appreciation of the embryology of the heart and great vessels are presented. It was widely accepted that all structures developed from the primitive heart tube; it is now recognized that other primitive cells from the anterior or secondary heart field, as well as neural crest cells, are major contributors to cardiac and great vessel formation. Their importance in development of congenital cardiovascular malformations is now being explored.
The association of neurological abnormalities with congenital cardiovascular malformations has been recognized for many years; in many genetic syndromes, both developmental delay and cardiac defects are encountered. In recent years, concern has been raised regarding intellectual and behavioral impairment in children with several congenital cardiac anomalies. The possibility that this was related to surgical procedures during infancy was considered, but recent evidence suggests interference with brain development occurs during fetal life. In a most interesting new chapter, authored by Dr. Patrick McQuillen, neurological development and mechanisms by which congenital cardiovascular malformations could affect it are presented. This topic is of great importance, because it is suggested that in some infants with these cardiac lesions, correction during the neonatal period may not improve the neurological deficit. This would support the concept of intervention to correct the circulatory disturbance during fetal life.
The use of nonsurgical approaches to cardiac lesions has become standard practice over the past decade. Many of these procedures are not yet applicable to neonates, but as discussed in this edition, interventions to relieve aortic and pulmonary stenoses by balloon valvuloplasty have now become standard practice, thus avoiding the high risks of surgery in critically ill infants.
This edition of Neonatal Cardiology continues to provide pediatric cardiologists, neonatologists, and obstetricians with an invaluable resource for the differential diagnosis of cardiovascular disturbances and their management in newborn infants. The symptom-complex approach is particularly helpful to students and residents in understanding the mechanisms responsible for clinical manifestations.