Ventricular septal defect with normally connected and with transposed great arteries

The morphologic characteristics of 50 hearts with ventricular septal defect (VSD) and ventriculoarterial (VA) discordance were compared with those of 105 hearts with VSD and VA concordance. Of the 7 VSD types in VA concordant hearts, the 3 that occur most frequently--central muscular (26%), perimembranous with leftward malalignment of the outlet septum (18%) and perimembranous with overriding posterior artery (15%)--were absent in VA discordant hearts. Of the 6 with VA discordance, 2 principal VSD types (perimembranous with rightward outlet septum malalignment [25%] and muscular infundibular with leftward outlet septum malalignment [15%]) did not occur in VA concordant specimens. Thus, 4 VSD types occurred with VA concordance as well as with VA discordance: subarterial (12% concordance, 3% discordance); perimembranous inlet (15%, 27%); muscular inlet (10%, 27%); and membranous (4%, 3%). Of these 4 common groups, perimembranous inlet VSD with VA concordance was accompanied by tricuspid valve anomalies; however, mitral valve anomalies complicated this type of VSD with VA discordance. It is concluded that in hearts with VA concordance vs hearts with VA discordance the spectrum of VSD and ventricular morphology is different.