Other congenital malformations of heart (Q24) ICD-10-CM
The Q24 code range covers other congenital malformations of heart with 10 ICD-10-CM diagnosis codes. 9 of them are billable and valid for claim submission in fiscal year 2027, and the category headers group them but cannot themselves be billed.
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
- endocardial fibroelastosis I42.4
Codes in the Q24 Range 10 codes · 9 billable
- Q24 Other congenital malformations of heartNon-billable
- Q24.0 Dextrocardia
- Q24.1 Levocardia
- Q24.2 Cor triatriatum
- Q24.3 Pulmonary infundibular stenosis
- Q24.4 Congenital subaortic stenosis
- Q24.5 Malformation of coronary vessels
- Q24.6 Congenital heart block
- Q24.8 Other specified congenital malformations of heart
- Q24.9 Congenital malformation of heart, unspecified
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the Q24 range.
Cor Triatriatum
A malformation of the heart in which the embryonic common PULMONARY VEIN was not incorporated into the LEFT ATRIUM leaving behind a perforated fibromuscular membrane bisecting the left atrium, a three-atrium heart. The opening between the two left atrium sections determines the degree of obstruction to pulmonary venous return, pulmonary venous and pulmonary arterial hypertension.
Dextrocardia
A congenital defect in which the heart is located on the right side of the THORAX instead of on the left side (levocardia, the normal position). When dextrocardia is accompanied with inverted HEART ATRIA, a right-sided STOMACH, and a left-sided LIVER, the combination is called dextrocardia with SITUS INVERSUS. Dextrocardia may adversely affect other thoracic organs.
Ectopia Cordis
A rare developmental defect in which the heart is abnormally located partially or totally outside the THORAX. It is the result of defective fusion of the anterior chest wall. Depending on the location of the heart, ectopia cordis can be thoracic, thoracoabdominal, abdominal, and cervical.
Levocardia
Congenital abnormalities in which the HEART is in the normal position (levocardia) in the left side of the chest but some or all of the THORAX or ABDOMEN viscera are transposed laterally (SITUS INVERSUS). It is also known as situs inversus with levocardia, or isolated levocardia. This condition is often associated with severe heart defects and splenic abnormalities such as asplenia or polysplenia.
Pulmonary Subvalvular Stenosis
Narrowing below the PULMONARY VALVE or well below it in the infundibuluar chamber where the pulmonary artery originates, usually caused by a defective VENTRICULAR SEPTUM or presence of fibrous tissues. It is characterized by restricted blood outflow from the RIGHT VENTRICLE into the PULMONARY ARTERY, exertional fatigue, DYSPNEA, and chest discomfort.
About the Q24 Code Range
These heart malformations are present at birth and belong to the larger group of congenital circulatory system malformations.
The subdivisions distinguish dextrocardia (Q24.0), levocardia (Q24.1) and cor triatriatum (Q24.2). Separate codes identify pulmonary infundibular stenosis (Q24.3), congenital subaortic stenosis (Q24.4), coronary vessel malformations (Q24.5) and congenital heart block (Q24.6). The remaining subdivisions are for other specified (Q24.8) and unspecified (Q24.9) congenital heart malformations.
Questions About This Page
How many billable codes are in the Q24 range?
Of the 10 codes in this range, 9 are billable and valid for claim submission from October 1, 2026 through September 30, 2027. Category header codes group them but cannot be reported on claims.
What does the Q24 range classify?
The range classifies other congenital malformations of heart. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2027 ICD-10-CM Tabular List and order file, effective October 1, 2026 through September 30, 2027.
