A clinical commentary on the article "biomaterials advances in patches for congenital heart defect repair" : cardiac bioengineering for congenital heart disease: time for progress.

Congenital heart disease remains the most common birth defect affecting almost 1% of the population and if one considers congenitally bicuspid aortic valves, the number of affected individuals rises to as much as 4% by many estimates. The spectrum of congenital heart disease is broad. Patients may have very complex structural anomalies including an absence of a ventricle (single ventricle), lack of connection to a great artery (aortic or pulmonary atresia), anomalies of venous connections (systemic or pulmonary venous), valvar abnormalities (semilunar and/or atrioventricular), abnormal connections (transposition or malalignment), and vascular hypoplasia (aortic coarctation, hypoplasia, or interruption). Individuals affected by variations of these problems may present with acute circulatory compromise immediately at birth, later in infancy or on more rare occasions, later in life. The physiology at presentation relates to the structural morphology and may include cyanosis, low cardiac output (shock), arterial or venous obstruction, excessive pulmonary blood flow, and congestive heart failure. It has long been recognized that infants presenting with symptomatic congenital heart disease have an overall very poor prognosis if left untreated. On the less structurally complex end of the spectrum, patients may present with defects between cardiac chambers in isolation or in combination with other problems. Defects of the atrial or ventricular septa are most commonly observed. Again, there is very broad range of symptomatology and physiology relating to the type, size, location, and number of septal defects. For larger defects, with significant intracardiac shunting of blood, the patient’s shortand long-term prognosis may be significantly affected if the lesion is left untreated. Surgical, and more recently, catheter-based treatments for serious congenital cardiac defects represent a true success story of modern medicine. The earliest palliative surgeries, performed in the 1930s (ligation of patent ductus arteriosus and coarctation repair) and 1940s (creation of a systemicto-pulmonary artery shunt) ushered in the era of physiologic treatment for congenital heart disease. In subsequent decades, enormous progress was made in addressing more and more complex conditions including aggressive reconstructions. In the 1950s, cardiopulmonary bypass to support the systemic circulation offered the prospect of intracardiac correction (tetralogy of Fallot, atrioventricular canal, and atrial/ventricular septal defects). In the 1960s and 1970s, durable palliations were developed for single ventricle (Glenn and Fontan procedures). The 1980s saw increasingly aggressive operations for serious defects in newborns and small babies (transposition of the great arteries, truncus arteriosus, aortic interruption, and ultimately, very complex lesions including hypoplastic left heart syndrome). In the 1990s and the first decade of the new millennium, treatments have been further refined to improve operative survival, reduce morbidity, and consider long-term outlook including neurodevelopmental opportunities. Recent striking advances have included successful surgical correction of complex lesions in very small, preterm neonates, the development and implementation of catheter-based treatments for many conditions, and in utero interventions for fetuses with critical cardiac conditions. This article is a commentary on the following article: 10.1007/s12265011-9289-8.