Diagnosis
Review of the cases show that, on presentation, the great majority of patients had evidence of congestive cardiac failure and pulmonary hypertension in early infancy, with these features often reported in the neonatal period when associated lesions are present. The chest roentgenogram usually reveals a moderate increase in the cardiothoracic ratio, along with pulmonary plethora. When present, multiple muscular defects are more frequently diagnosed by transesophageal color coded echocardiography, rather than transthoracic echocardiography. The identification of the morphology, and location, of the defects is important for selection of the appropriate therapeutic approach (Figures 2A, 2B).1-32,37-78
Some investigators have performed “en-face” reconstruction of multiple septal defects as viewed from the right ventricle, based on orthogonal echocardiographic views, so as to plan the surgical approach, and predict the likelihood of postoperative heart block or the occurrence of residual defects. Features noted have included the location and dimensions of the defects, the distance of separation between additional defects, the relationship to various right ventricular septal landmarks.37 Contrast-enhanced and multidetector computed-tomographic angiocardiography in angled oblique views have also proved helpful in ascertaining the morphology and location of the septal defects, together with evaluation of the aortic arch and its branches (Figures 3A-3F, 4A-4F). Cardiac catheterization and angiocardiography may still be indicated in some circumstances for evaluation of associated cardiac anomalies. Despite echocardiography and angiocardiography, it can still be difficult to recognize the boundaries of the defect, particularly in the setting of the Swiss-cheese septum.1-32,37-73 Indeed, we found several reports describing additional defects recognized in the intraoperative and postoperative period, as well as at necropsy.7,13
Associated cardiac and extracardiac anomalies were reported in one-third to three-quarters of patients. Cardiac anomalies included common atrium, Ebstein-like anomaly of the tricuspid valve with tricuspid stenosis or regurgitation, endocardial fibroelastosis of the right ventricle, pulmonary stenosis, patchy-endocardial sclerosis of the left ventricle, downward displacement of the tricuspid valve, aneurysm of the membranous septum, midline heart, juxtaposed right atrial appendages, double orifice mitral valve with mitral stenosis, double outlet right ventricle, Taussig-Bing anomaly, atrioventricular septal defect, bilateral superior caval veins, subaortic stenosis, left superior caval vein to coronary sinus, unroofed coronary sinus, tetralogy of Fallot, atretic orifice of the coronary sinus, common arterial trunk, straddling tricuspid valve, partially anomalous pulmonary venous connection, transposition, right isomerism, pulmonary atresia, divided left atrium, left isomerism, left ventricular outflow tract obstruction, interruption of inferior caval vein, hypoplastic left ventricle, hypoplastic right ventricle, congenital aortic stenosis, congenitally corrected transposition, and criss-cross ventricles. Associated extracardiac anomalies included patency of the arterial duct, hypoplasia of aortic isthmus, coarctation of aorta, interrupted aortic arch, double aortic arch, and hypoplastic aortic arch.6-8,13-16,18,19,23,24,31,32,37