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v1.0.0
ICD-10 Guide
ICD-10 CodesB33.21

B33.21

Viral endocarditis

BILLABLE STATUSYes
IMPLEMENTATION DATEOctober 1, 2015
LAST UPDATED09/05/2025

Code Description

ICD-10 B33.21 is a billable code used to indicate a diagnosis of viral endocarditis.

Key Diagnostic Point:

Viral endocarditis is an inflammation of the inner lining of the heart chambers and valves caused by viral infections. Unlike bacterial endocarditis, which is more common and often associated with pre-existing heart conditions, viral endocarditis can occur in healthy individuals. Common viral pathogens include Coxsackievirus, Cytomegalovirus (CMV), and Epstein-Barr virus (EBV). The clinical presentation may vary widely, ranging from mild symptoms such as fever and fatigue to severe manifestations like heart failure or embolic events. Diagnosis typically involves a combination of clinical evaluation, echocardiography, and serological tests to identify the specific viral agent. Antiviral treatments may be indicated depending on the underlying viral infection, although management often focuses on supportive care and monitoring. The condition can be challenging to diagnose due to its nonspecific symptoms and the overlap with other forms of endocarditis, necessitating a thorough clinical assessment and appropriate laboratory investigations.

Code Complexity Analysis

Complexity Rating: Medium

Medium Complexity

Complexity Factors

  • Differentiation from bacterial endocarditis
  • Variety of viral pathogens involved
  • Need for specific diagnostic tests
  • Potential for overlapping symptoms with other conditions

Audit Risk Factors

  • Inadequate documentation of viral etiology
  • Failure to document clinical symptoms clearly
  • Lack of supporting diagnostic test results
  • Misclassification with bacterial endocarditis

Specialty Focus

Medical Specialties

Cardiology

Documentation Requirements

Detailed clinical notes on symptoms, diagnostic tests performed, and treatment plans.

Common Clinical Scenarios

Patients presenting with fever, heart murmurs, and echocardiographic findings suggestive of endocarditis.

Billing Considerations

Ensure clear documentation of viral testing and differentiation from bacterial causes.

Infectious Disease

Documentation Requirements

Comprehensive history of viral infections, laboratory results, and treatment responses.

Common Clinical Scenarios

Patients with a known viral infection presenting with cardiac symptoms.

Billing Considerations

Document the specific viral pathogen identified and the rationale for antiviral therapy.

Coding Guidelines

Inclusion Criteria

Use B33.21 When
  • Follow the official ICD
  • CM coding guidelines, ensuring accurate documentation of the viral etiology and clinical manifestations
  • Include any relevant laboratory findings and diagnostic imaging results

Exclusion Criteria

Do NOT use B33.21 When
No specific exclusions found.

Related CPT Codes

93306CPT Code

Echocardiography, transthoracic, real-time with interpretation

Clinical Scenario

Used to assess cardiac function and structure in suspected endocarditis cases.

Documentation Requirements

Document the indication for the echocardiogram and findings.

Specialty Considerations

Cardiology specialists should ensure comprehensive reporting of echocardiographic findings.

ICD-10 Impact

Diagnostic & Documentation Impact

Enhanced Specificity

ICD-10 Improvements

The transition to ICD-10 has allowed for more specific coding of viral endocarditis, improving the accuracy of data collection and reimbursement processes. It enables better tracking of viral infections and their impact on cardiac health.

ICD-9 vs ICD-10

The transition to ICD-10 has allowed for more specific coding of viral endocarditis, improving the accuracy of data collection and reimbursement processes. It enables better tracking of viral infections and their impact on cardiac health.

Reimbursement & Billing Impact

reimbursement processes. It enables better tracking of viral infections and their impact on cardiac health.

Resources

Clinical References

  • •
    CDC Viral Endocarditis Guidelines

Coding & Billing References

  • •
    CDC Viral Endocarditis Guidelines

Frequently Asked Questions

What are the common viral pathogens associated with viral endocarditis?

Common viral pathogens include Coxsackievirus, Cytomegalovirus (CMV), and Epstein-Barr virus (EBV).

How is viral endocarditis diagnosed?

Diagnosis involves clinical evaluation, echocardiography, and serological tests to identify the specific viral agent.

What treatments are available for viral endocarditis?

Treatment may include antiviral medications depending on the viral infection, but often focuses on supportive care.