2027 ICD-10-CM Diagnosis Code Q24.6Congenital heart block
ICD-10-CM Codes›Q00-Q99›Q20-Q28›Q24
- Billable — Valid for Submission
- MCC — Major Complication or Comorbidity
- POA Exempt
- Chronic Condition
Q24.6 is a billable ICD-10-CM diagnosis code for congenital heart block. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 308 through 310. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 59 closely related codes. The code is exempt from POA reporting. Coders also document this condition as complete atrioventricular block. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Cardiac and circulatory congenital anomalies.
Code Identity
Code Classification
Present on Admission (POA)Billing
Q24.6 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review the other POA exempt codes in Congenital malformations of the circulatory system (Q20-Q28).
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Complete atrioventricular block
- Congenital complete atrioventricular heart block
- Congenital conduction defect
- Congenital heart block
- Congenital incomplete atrioventricular heart block
- Partial atrioventricular block
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to Q24.6: its own notes plus those printed at Q24 and Chapter 17. A note printed at a category, block or chapter applies to every code under it.
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
Notes
General instructions on how these codes are used.
- Codes from this chapter are not for use on maternal records
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name Q24.6, its category, or a range that includes it.
Use Additional Code 1
These codes say to use an additional code from the note, and Q24.6 is one of the codes named.
- Q87.88 CTNNB1 syndrome
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Arrhythmia
An arrhythmia is a problem with the rate or rhythm of your heartbeat. Your heart beats too quickly, too slowly, or with an irregular pattern. Changes in the electrical signals that control your heartbeat cause arrhythmias.
The full article covers:
- What is an arrhythmia?
- What causes an arrhythmia?
- What are the symptoms of an arrhythmia?
- How is an arrhythmia diagnosed?
- What are the treatments for an arrhythmia?
- Can arrhythmias be prevented?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert Q24.6 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About Q24.6Overview
What is the ICD-10 code for congenital heart block?
The ICD-10-CM code for congenital heart block is Q24.6 (sometimes written as Q246). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is Q24.6 (Other congenital malformations of heart) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report congenital heart block on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does Q24.6 group to?
When congenital heart block is the principal diagnosis on an inpatient stay, it groups to MS-DRG 309, 310, 308, with relative weights from 0.5686 to 1.1809 depending on complications. Higher weights mean higher Medicare reimbursement.
Is Q24.6 a CC or MCC?
CMS lists Q24.6 as an MCC (major complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 59 closely related codes in its exclusion list.
Is Q24.6 exempt from POA reporting?
Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for congenital heart block on inpatient claims. The code appears in the Congenital malformations of the circulatory system (Q20-Q28) range of the CMS exempt list.
