Q40-Q48
Medium Complexity

Congenital malformations of the circulatory system

Primary Specialty: Pediatrics
Last Updated: 2025-09-10

ICD-10 Codes (43)

40 billable
0 category headers
Q41
Congenital absence, atresia and stenosis of small intestine
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Q41.0
Billable
Congenital absence, atresia and stenosis of duodenum
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Q41.1
Billable
Congenital absence, atresia and stenosis of jejunum
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Q41.2
Billable
Congenital absence, atresia and stenosis of ileum
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Q41.8
Billable
Congenital absence, atresia and stenosis of other specified parts of small intestine
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Q41.9
Billable
Congenital absence, atresia and stenosis of small intestine, part unspecified
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Q42
Billable
Congenital absence, atresia and stenosis of large intestine
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Q42.0
Billable
Congenital absence, atresia and stenosis of rectum with fistula
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Q42.1
Billable
Congenital absence, atresia and stenosis of rectum without fistula
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Q42.2
Billable
Congenital absence, atresia and stenosis of anus with fistula
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Q42.3
Billable
Congenital absence, atresia and stenosis of anus without fistula
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Q42.8
Billable
Congenital absence, atresia and stenosis of other parts of large intestine
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Q42.9
Billable
Congenital absence, atresia and stenosis of large intestine, part unspecified
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Q43
Billable
Other congenital malformations of intestine
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Q43.0
Billable
Meckel's diverticulum (displaced) (hypertrophic)
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Q43.1
Billable
Hirschsprung's disease
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Q43.2
Billable
Other congenital functional disorders of colon
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Q43.3
Billable
Congenital malformations of intestinal fixation
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Q43.4
Billable
Duplication of intestine
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Q43.5
Billable
Ectopic anus
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Q43.6
Billable
Congenital fistula of rectum and anus
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Q43.7
Billable
Persistent cloaca
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Q43.8
Billable
Other specified congenital malformations of intestine
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Q43.9
Billable
Congenital malformation of intestine, unspecified
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Q44
Congenital malformations of gallbladder, bile ducts and liver
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Q44.0
Billable
Agenesis, aplasia and hypoplasia of gallbladder
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Q44.1
Billable
Other congenital malformations of gallbladder
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Q44.2
Billable
Atresia of bile ducts
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Q44.3
Billable
Congenital stenosis and stricture of bile ducts
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Q44.4
Billable
Choledochal cyst
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Q44.5
Billable
Other congenital malformations of bile ducts
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Q44.6
Billable
Cystic disease of liver
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Q44.7
Billable
Other congenital malformations of liver
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Q44.70
Billable
Other congenital malformation of liver, unspecified
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Q44.71
Billable
Alagille syndrome
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Q44.79
Billable
Other congenital malformations of liver
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Q45
Other congenital malformations of digestive system
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Q45.0
Billable
Agenesis, aplasia and hypoplasia of pancreas
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Q45.1
Billable
Annular pancreas
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Q45.2
Billable
Congenital pancreatic cyst
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Q45.3
Billable
Other congenital malformations of pancreas and pancreatic duct
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Q45.8
Billable
Other specified congenital malformations of digestive system
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Q45.9
Billable
Congenital malformation of digestive system, unspecified
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Updates & Changes

FY 2026 Updates

Current Year

New Codes (1)

Q23.4
Hypoplastic left heart syndrome with mitral atresia

Revised Codes (1)

Q21.0
Ventricular septal defect - updated to include hemodynamic significance when known

Deleted Codes

No codes deleted in this range for FY 2026

Historical Changes

  • •FY 2025: Routine maintenance updates with minor terminology clarifications
  • •FY 2024: Enhanced specificity requirements for certain code ranges
  • •FY 2023: Updated documentation guidelines for improved clarity

Upcoming Changes

  • •Proposed updates pending review by Coordination and Maintenance Committee
  • •Under consideration: Enhanced digital health integration codes

Implementation Guidance

  • •Review all FY 2026 updates for Q40-Q48 codes before implementation
  • •Always verify the most current codes in the ICD-10-CM manual
  • •Ensure clinical documentation supports the selected diagnosis codes
  • +3 more guidance items...

Range Overview

high priority

The ICD-10 category Q40-Q48 pertains to congenital malformations of the circulatory system. These codes are used to document congenital anomalies such as septal defects, coarctation of the aorta, and congenital anomalies of pulmonary and systemic vessels. The codes in this range are crucial for accurate medical documentation and billing, as well as for epidemiological studies and health management.

Key Usage Points:

  • •Always code to the highest level of specificity.
  • •Use additional codes to identify any associated conditions or complications.
  • •Use additional code to identify any history of tobacco use or exposure.
  • •For newborns, also code any condition classifiable to P29.3.
  • •Use additional code from category Z87.74 if applicable.

Coding Guidelines

When to Use:

  • ✓When a patient has a congenital malformation of the circulatory system.
  • ✓When a patient's congenital circulatory system malformation has caused complications.
  • ✓When a patient's congenital circulatory system malformation is relevant to their current health status.
  • ✓When a patient's congenital circulatory system malformation affects their treatment plan.

When NOT to Use:

  • ✗When a patient has an acquired circulatory system disorder.
  • ✗When a patient's congenital circulatory system malformation has been corrected and is no longer relevant to their health status.
  • ✗When a patient's circulatory system disorder is not confirmed to be congenital.
  • ✗When a patient's circulatory system disorder is not the focus of the current medical encounter.

Code Exclusions

Always verify that the condition is congenital and not acquired before using a code from this range.

Documentation Requirements

Documentation for codes in this range should include a detailed description of the congenital malformation, any associated conditions or complications, and the impact of the malformation on the patient's health status and treatment plan.

Clinical Information:

  • •Detailed description of the congenital malformation.
  • •Any associated conditions or complications.
  • •Impact of the malformation on the patient's health status.
  • •Impact of the malformation on the patient's treatment plan.

Supporting Evidence:

  • •Medical history.
  • •Physical examination findings.
  • •Diagnostic test results.
  • •Operative reports if applicable.
Good Documentation Example:

Patient has a congenital ventricular septal defect, which is causing increased pulmonary blood flow and symptoms of heart failure. The defect is being managed medically at this time.

Poor Documentation Example:

Patient has a heart defect.

Common Documentation Errors:

  • âš Not coding to the highest level of specificity.
  • âš Not documenting associated conditions or complications.
  • âš Not documenting the impact of the malformation on the patient's health status and treatment plan.

Range Statistics

9
Total Codes
40
Billable
Complexity:
Medium
Primary Use:Clinical Documentation
Chapter:17

Coding Complexity

Medium
Complexity Rating

Coding for congenital malformations of the circulatory system can be complex due to the need to determine whether a condition is congenital or acquired, code to the highest level of specificity, and identify and code associated conditions or complications. Additionally, understanding the impact of the malformation on the patient's health status and treatment plan is crucial for accurate coding.

Key Factors:
  • â–¸Determining whether a condition is congenital or acquired.
  • â–¸Coding to the highest level of specificity.
  • â–¸Identifying and coding associated conditions or complications.
  • â–¸Understanding the impact of the malformation on the patient's health status and treatment plan.

Specialty Focus

Codes in this range are primarily used by pediatricians, cardiologists, and cardiothoracic surgeons. They may also be used by other specialists who manage patients with congenital circulatory system malformations.

Primary Specialties:
Pediatrics
40%
Cardiology
30%
Cardiothoracic Surgery
30%
Clinical Scenarios:
  • • Newborn with cyanosis and a murmur found to have tetralogy of Fallot.
  • • Infant with failure to thrive found to have a large ventricular septal defect.
  • • Adult with a history of congenital heart disease presenting for evaluation of heart failure symptoms.
  • • Patient undergoing surgical correction of a congenital heart defect.

Resources & References

Resources for coding congenital malformations of the circulatory system include the ICD-10-CM Official Guidelines for Coding and Reporting, the American Heart Association's Coding Clinic, and various medical textbooks and journals.

Official Guidelines:

  • ICD-10-CM Official Guidelines for Coding and Reporting
  • American Heart Association Coding Clinic
  • American Academy of Pediatrics Guidelines

Clinical References:

  • Nelson Textbook of Pediatrics
  • Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine

Educational Materials:

  • American Academy of Professional Coders (AAPC) Training
  • American Health Information Management Association (AHIMA) Training

Frequently Asked Questions

How do I code a congenital heart defect that has been surgically corrected?

If the defect has been surgically corrected and is no longer affecting the patient's health status, it should be coded as a personal history of the defect (Z87.74). If the defect is still affecting the patient's health status, it should be coded as a current condition (Q20-Q28).