(BQ) Part 2 book “A practical guide to fetal echocardiography normal and abnormal hearts” has contents: Aortic stenosis and bicuspid aortic valve, common arterial trunk, fetal arrhythmias, fetal cardiomyopathies and fetal heart tumors, and other contents. | ● UNIVENTRICULAR ATRIOVENTRICULAR CONNECTION Univentricular atrioventricular connection describes a group of cardiac malformations where the atrioventricular connection is completely or predominantly to a single ventricular chamber. Embryologically, this malformation is thought to result from failure of the development of the bulboventricular loop stage. Much debate still exists today on the various subclassifications of cardiac anomalies within this group and what should be included or excluded (1–4). From a clinical point of view, a congenital heart defect with a univentricular atrioventricular connection, single ventricular physiology, describes a heart with one functioning ventricle with inflow from one or both atria. Numerous terms were used to describe this malformation, including univentricular heart, primitive ventricle, common ventricle, single ventricle, cor triloculare biatriatum, cor biloculare, dominant ventricle, and double inlet ventricle (DIV) (3). The classic Van Praagh classification (5), which was later modified by Hallermann et al. (6), described one or two atrioventricular valves that empty into a single ventricle and excluded mitral or tricuspid atresia (TA). Anderson’s simpler classification described a single ventricular mass with or without a rudimentary chamber and allowed for the inclusion of mitral or TA (7, 8). In Anderson’s classification, the rudimentary chamber, if present, should not have an inlet but may have an outlet (7, 8). Within univentricular atrioventricular connection, three subgroups can be identified: double inlet, where two atria connect to a single ventricle through two patent atrioventricular valves; single inlet, where one atrium connects to a single ventricle through a single atrioventricular valve; and common inlet, where both atria connect to a single ventricle through a single atrioventricular valve (1). The morphology of the ventricle is generally a left ventricular morphology with a rudimentary right .