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v1.0.0
ICD-10 Guide
ICD-10 CodesQ21.10

Q21.10

Billable

Atrial septal defect, unspecified

BILLABLE STATUSYes
IMPLEMENTATION DATEOctober 1, 2015
LAST UPDATED09/11/2025

Code Description

ICD-10 Q21.10 is a billable code used to indicate a diagnosis of atrial septal defect, unspecified.

Key Diagnostic Point:

An atrial septal defect (ASD) is a congenital heart defect characterized by an opening in the septum that divides the two upper chambers of the heart (the atria). This defect allows blood to flow from the left atrium to the right atrium, leading to increased blood flow to the lungs and potential complications such as pulmonary hypertension and heart failure. The severity of an ASD can vary, with some individuals experiencing minimal symptoms while others may require surgical intervention. ASDs can be classified into several types, including ostium primum, ostium secundum, and sinus venosus defects, but when unspecified, it indicates that the specific type has not been determined. Early diagnosis is crucial, often made through echocardiography, and management may involve monitoring, medication, or surgical repair depending on the size of the defect and the presence of symptoms. Understanding the implications of ASDs is essential for pediatric care, as they can impact growth, development, and overall health.

Code Complexity Analysis

Complexity Rating: Medium

Medium Complexity

Complexity Factors

  • Variability in clinical presentation and severity of symptoms
  • Need for precise documentation of defect type and size
  • Potential for associated congenital anomalies
  • Differentiation from other congenital heart defects

Audit Risk Factors

  • Inadequate documentation of the defect type
  • Failure to document associated conditions
  • Incorrect coding of severity or symptoms
  • Lack of follow-up documentation post-surgery

Specialty Focus

Medical Specialties

Pediatrics

Documentation Requirements

Detailed clinical history, physical examination findings, and results from diagnostic imaging such as echocardiograms.

Common Clinical Scenarios

Routine check-ups for children with known ASDs, pre-operative assessments, and post-operative follow-ups.

Billing Considerations

Consideration of growth and developmental milestones in children with ASDs, as well as the psychosocial impact on families.

Genetics

Documentation Requirements

Family history of congenital heart defects, genetic testing results, and counseling notes.

Common Clinical Scenarios

Assessment of genetic syndromes associated with congenital heart defects, such as Down syndrome.

Billing Considerations

Understanding the genetic implications of ASDs and their association with chromosomal abnormalities.

Coding Guidelines

Inclusion Criteria

Use Q21.10 When
  • Follow the official ICD
  • CM guidelines for coding congenital malformations, ensuring that the documentation supports the diagnosis and any associated conditions

Exclusion Criteria

Do NOT use Q21.10 When
No specific exclusions found.

Related ICD-10 Codes

Related CPT Codes

93306CPT Code

Echocardiography, transthoracic, real-time with interpretation

Clinical Scenario

Used for initial diagnosis and follow-up of ASD.

Documentation Requirements

Echocardiogram report detailing findings related to ASD.

Specialty Considerations

Pediatric cardiology may require specific echocardiographic views.

ICD-10 Impact

Diagnostic & Documentation Impact

Enhanced Specificity

ICD-10 Improvements

The transition to ICD-10 has allowed for more specific coding of congenital heart defects, improving the accuracy of data collection and reimbursement processes.

ICD-9 vs ICD-10

The transition to ICD-10 has allowed for more specific coding of congenital heart defects, improving the accuracy of data collection and reimbursement processes.

Reimbursement & Billing Impact

reimbursement processes.

Resources

Clinical References

  • •
    American Academy of Pediatrics - Congenital Heart Disease

Coding & Billing References

  • •
    American Academy of Pediatrics - Congenital Heart Disease

Frequently Asked Questions

What is the difference between Q21.10 and Q21.1?

Q21.10 refers to an unspecified atrial septal defect, while Q21.1 specifies an ostium secundum atrial septal defect, which is a common type of ASD. Accurate coding requires documentation of the specific type when known.