Partial anomalous pulmonary venous connection

This code describes a congenital heart defect where some, but not all, of the pulmonary veins drain abnormally into the systemic venous circulation (e.g., superior vena cava, right atrium) instead of the left atrium. This results in a left-to-right shunt, increasing blood flow to the right side of the heart and lungs. The severity depends on the number of veins involved and the size of the shunt.

Use this code when documentation clearly indicates a partial anomalous pulmonary venous connection (PAPVC) identified through diagnostic imaging such as echocardiography, CT angiography, or cardiac catheterization. This diagnosis is often made in pediatric cardiology or adult congenital heart disease settings.

• Differentiate from total anomalous pulmonary venous connection (TAPVC), where all pulmonary veins drain abnormally.
• Look for associated congenital heart defects, such as atrial septal defect (ASD), which often co-occurs with PAPVC.
• Ensure the documentation specifies "partial" to avoid miscoding with more severe forms of anomalous pulmonary venous return.