Q20Congenital malformations of cardiac chambers and connections

Q20 is the ICD-10-CM diagnosis code for congenital malformations of cardiac chambers and connections. It belongs to block Q20-Q28 (congenital malformations of the circulatory system) and chapter 17 (congenital malformations, deformations, chromosomal abnormalities, and genetic disorders). It is a header code, so it can't be reported by itself; one of its 9 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: Q20.0 (trunk), Q20.1 (ventricle), Q20.2 (ventricle), Q20.3 (connection), Q20.4 (ventricle), Q20.5 (connection), Q20.6 (appendages), Q20.8 (connections) and 1 more.

Don't report Q20 together with the conditions in its Excludes1 note: dextrocardia with situs inversus (Q89.3) and mirror-image atrial arrangement with situs inversus (Q89.3).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.