ICD-11

A congenital cardiac malformation in which there is an abnormality of a ventricle and/or the ventricular septum. The ventricles include the ventricular inlet, ventricular body and ventricular outflow tract.

A congenital cardiac malformation in which there is a hole or pathway between the ventricular chambers.

The definitions offered for a “ventricular septal defect”, in its various forms, will be used most frequently in the setting of patients who do not have abnormalities of either the atrioventricular or ventriculo-arterial connections. The definitions themselves, however, are equally applicable for the description and categorization of holes or pathways between the ventricles when the segmental connections between the cardiac components are abnormal. The key to understanding the definitions is to appreciate that the hole or pathway between the ventricles is defined both on the basis of its geographic location within the ventricular septum and its margins as seen from the aspect of the morphologically right ventricle. In this respect, when the ventriculo-arterial connections are concordant or discordant, the roof of the channel, as viewed from the right ventricle, is the muscular outlet septum or its fibrous remnant. When both arterial trunks arise from the morphologically right ventricle, in contrast, the channel between the ventricles provides the outflow from the morphologically left ventricle, and is roofed by the inner heart curvature. In the setting of double outlet right ventricle, therefore, the interventricular communication is not the same geometric locus as the ventricular septal defect, although many still continue to describe the outlet from the left ventricle as the “ventricular septal defect”. In univentricular atrioventricular connections with functionally single left ventricle with an outflow chamber, the communication, which used to be called a bulboventricular foramen, is both a ventricular septal defect and an interventricular communication. The situation in the setting of double outlet right ventricle, however, shows that the terms cannot always be used as being synonymous. A similar situation pertains in the setting of common arterial trunk, since the hole usually closed by the surgeon to provide septal integrity is the right ventricular margin of the channel between the ventricles, rather than the geometric interventricular communication.

A congenital cardiovascular malformation in which there is a ventricular septal defect that 1) occupies the space that is usually closed by the interventricular part of the membranous septum, 2) is usually adjacent to the area of fibrous continuity between the leaflets of an atrioventricular valve and an arterial valve, 3) is adjacent to an area of mitral-tricuspid fibrous continuity, and 4) is located at the center of the base of the ventricular mass.

Additional information: This code is used by some as synonymous with the perimembranous, conoventricular, Type II, or the paramembranous defects. Although best used to describe the perimembranous defect that opens centrally at the base of the right ventricle, this term might be used to code perimembranous defects with inlet or outlet extension. It is recommended, however, that the more precise terms be used whenever possible for coding the latter lesions. It should also not be used to code an inlet ventricular septal defect, or the so-called atrioventricular canal ventricular septal defect. More specific terms exist for coding these entities. It is used by some to describe an isolated perimembranous ventricular septal defect without extension, although it is unlikely that perimembranous defects exist in the absence of deficiency of their muscular perimeter. The conoventricular ventricular septal defect with malalignment should be coded as an outlet defect, as should the perimembranous defect opening to the outlet of the right ventricle. Such defects can also extend to become doubly committed and juxta-arterial (conal septal hypoplasia) when there is also fibrous continuity between the leaflets of the arterial valves or when there is a common arterial valve. Specific codes exist for these variants, which ideally should not be coded using this term.

This is a generic term that, if possible, should not be used in preference to more specific terms regarding the geographical site of the defect's extension: central and basally, to the right ventricular inlet, or to the right ventricular outlet. This code is used by some as synonymous with the conoventricular VSD, or the paramembranous VSD. It is also known as the type II VSD. It should not be used to code an inlet VSD, or the so-called atrioventricular canal VSD. More specific terms exist for coding these entities. It is used by some to describe an isolated perimembranous VSD without extension, although it is unlikely that perimembranous defects exist in the absence of deficiency of their muscular perimeter. The conoventricular VSD with malalignment should be coded as an outlet defect, as should the perimembranous defect opening to the outlet of the right ventricle. All perimembranous defects, nonetheless, have part of their margins made up of fibrous continuity either between the leaflets of an atrioventricular and an arterial valve or, in the setting of double outlet right ventricle or overriding of the tricuspid valve, by fibrous continuity between the leaflets of the mitral and tricuspid valves. Such defects can also extend to become doubly committed and juxta-arterial (conal septal hypoplasia) when there is also fibrous continuity between the leaflets of the arterial valve or when there is a common arterial valve.

Although best used to describe the perimembranous defect that opens centrally at the base of the right ventricle, this term might be used to code perimembranous defects with inlet or outlet extension. It is recommended, however, that the more precise terms be used whenever possible for coding the latter lesions. This code is used by some as synonymous with the perimembranous, conoventricular, Type II, or the paramembranous defects. It should not be used to code an inlet VSD, or the so-called atrioventricular canal VSD. More specific terms exist for coding these entities. It is used by some to describe an isolated perimembranous VSD without extension, although it is unlikely that perimembranous defects exist in the absence of deficiency of their muscular perimeter. The conoventricular VSD with malalignment should be coded as an outlet defect, as should the perimembranous defect opening to the outlet of the right ventricle. All perimembranous defects, nonetheless, have part of their margins made up of fibrous continuity either between the leaflets of an atrioventricular and an arterial valve or, in the setting of double outlet right ventricle or overriding of the tricuspid valve, by fibrous continuity between the leaflets of the mitral and tricuspid valves. Such defects can also extend to become doubly committed and juxta-arterial (conal septal hypoplasia) when there is also fibrous continuity between the leaflets of the arterial valves or when there is a common arterial valve. Specific codes exist for these variants, which ideally should not be coded using this term.