More than 1 million Americans have congenital heart defects, according to the Adult Congenital Heart Association (ACHA). Congenital heart defects (CHD) occur when the heart or blood vessels near the heart dont develop normally before birth. Most specialists dont know why they occur, but theyre always researching. Keep up with advances in this issue Guest Edited by Gary D. Webb, MD, FRCP(C), FACC, from the Philadelphia Adult Congenital Heart Center at the University of Pennsylvania School of Medicine. Chapters planned include syndromes encountered in adult CHD patients, sudden death in perspective in ACHD, pregnancy and congenital heart disease and more.