Q26.4 Anomalous pulmonary venous connection, unspecified

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis. Exempt from present-on-admission (POA) reporting.

Risk adjustment (HCC)

• RxHCC V08: HCC 191 — Ventricular Septal Defect and Major Congenital Heart Disorders

MS-DRG index

Defines the logic of DRG(s) 306-307 in MDC 05.

Approximate ICD-9-CM (GEMs)

• 747.42 Partial anomalous pulmonary venous connection (approximate)

Code annotations containing back-references to Q26.4

Back-references to Q26

• Code Also: I27.21 Secondary pulmonary arterial hypertension ("congenital heart disease (Q20-Q28)")
• Type 2 Excludes: P29 Cardiovascular disorders originating in the perinatal period ("congenital malformations of the circulatory system (Q20-Q28)")
• Code Also: Z71.87 Encounter for pediatric-to-adult transition counseling ("congenital malformations of the circulatory system (Q20-Q28)")

Diagnosis Index entries for Q26.4

• Anomaly, anomalous (congenital) (unspecified type) › connection › pulmonary venous
• Anomaly, anomalous (congenital) (unspecified type) › opening, pulmonary veins
• Anomaly, anomalous (congenital) (unspecified type) › pulmonary › venous connection
• Atresia, atretic › vein NEC › pulmonary
• Malformation (congenital) › great › vein › anomalous › pulmonary venous connection

Nearby codes

• Q26 Congenital malformations of great veins
• Q26.0 Congenital stenosis of vena cava
• Q26.1 Persistent left superior vena cava
• Q26.2 Total anomalous pulmonary venous connection
• Q26.3 Partial anomalous pulmonary venous connection
• Q26.4 Anomalous pulmonary venous connection, unspecified (this code)
• Q26.5 Anomalous portal venous connection
• Q26.6 Portal vein-hepatic artery fistula
• Q26.8 Other congenital malformations of great veins
• Q26.9 Congenital malformation of great vein, unspecified