encouraging.68–71 It can be very challenging to achieve a biventricular repair in patients with noncommitted interventricular communications Reported outcome is therefore biased by the multitude of surgical techniques used and the variability of the anatomy Although a noncommitted interventricular communication has been reported as posing a higher risk,63,65 other groups did not find worse outcomes.62,72,73 Successful biventricular repair can be achieved in a substantial number of well-selected patients with favorable results.61,73 In the very complex cases that make biventricular repair challenging, functionally single-ventricle physiology and staged conversion to the Fontan circulation may be a valuable alternative.63 Patients with noncommitted interventricular communication, in particular, tend to be allocated to functionally single ventricular palliation.20 If associated defects―such as straddling of the atrioventricular valves or hypoplasia of a ventricle―are present, the functionally single-ventricle pathway should be preferred over biventricular repair.61 In our experience, risk factors for achieving a functionally single-ventricle repair were later birth cohort, hypoplastic left ventricle, double-inlet left ventricle, an interventricular communication in a nonsubaortic position, absence of hepatic venous malformations, and fetal diagnosis.20 Reintervention is common and reaches rates of 50%.70 This rate does not differ between surgical strategies but the respective reason for reintervention changes with the anatomic subtype.67 Subaortic valve obstruction, rather than right ventricular outflow tract pathology, was the main reason for reoperation in both patients with intraventricular repair or intraventricular repair and concomitant right ventricular outflow tract procedure as opposed to aorticrelated or aortic valve–related problems in patients after the arterial switch procedures.67 In patients after biventricular repair, right and left ventricular outflow tract procedures, as well as reintervention on the pulmonary arteries were most common.20 Patients converted to the Fontan circulation predominantly underwent fenestration closure and coil occlusion of collateral vessels.20 Few data are available on the postoperative outcome of double-outlet left ventricle In an older series reported by the authors, survival was 75% at 1 year and 67% at 18 years, with no significant difference between functionally univentricular and biventricular strategies.19 In a more recent analysis, survival of 87% after biventricular repair has been reported by others.74 Even though patient outcomes may be considered similar to those of patients with doubleoutlet right ventricle,66 the high proportion of functional abnormalities and the morphologic heterogeneity of this defect mandate careful interpretation of the results and an individual approach to the management of these patients Annotated References van Praagh R, David I, Wright GB, van Praagh S Large RV plus small LV is not single RV Circulation 1980;61(5):1057–1058 This crucial concept, stated in a letter to the editor, pointed out that it was philosophically unsound to base definitions of a given structure on one of its parts that was variable Instead, they established the crucial principle of the morphological method, stating that the structures be identified on the basis of their most constant components Ebadi A, Spicer DE, Backer CL, Fricker FJ, Anderson RH Double-outlet right ventricle revisited J Thorac Cardiovasc Surg 2017;1–8 A detailed discussion on the variability of infundibular morphology in double-outlet right ventricle Van Mierop LHS, Wiglesworth FW Pathogenesis of transposition complexes: II Anomalies due to faulty transfer of the posterior great artery Am J Cardiol 1963;12(2):226–232 An early discussion of the morphogenesis of doubloutlet right ventricle, which claims that doubleoutlet left ventricle is an embryological