What are the implications and recommended course of action for a pediatric or adult patient with a congenital heart defect where the pulmonic valve is positioned above the aortic valve, as indicated by an echocardiogram (echo)?

Pulmonic Valve Above Aortic Valve on Echocardiogram

Immediate Interpretation

This echocardiographic finding represents the normal anatomic position of the pulmonary valve, which is always located anterior and superior to the aortic valve in standard cardiac anatomy. 1 This is not a pathologic finding but rather confirms normal spatial relationships between the great vessels.

Normal Cardiac Anatomy and Echocardiographic Views

The pulmonary valve is visualized from the parasternal short-axis view at the level of the aortic valve, where it appears anterior and leftward (superior) to the aortic valve 1. This spatial relationship is consistent across all patients with normal cardiac anatomy:

• In the parasternal short-axis view, the pulmonary valve sits at approximately the 11 o'clock position relative to the aortic valve, which occupies the center of the image 1
• The right ventricular outflow tract courses anteriorly and superiorly from the right ventricle to reach the pulmonary artery, naturally positioning the pulmonary valve above the aortic valve 1
• Visualization is typically limited to one or two leaflets of the pulmonary valve simultaneously on 2D echocardiography, which is normal and expected 1

When This Finding Requires Further Evaluation

While the superior position of the pulmonary valve is normal, the echocardiogram should be carefully reviewed for actual pathology:

Assess for Pulmonary Valve Abnormalities

• Evaluate valve structure for bicuspid or quadricuspid morphology, doming, prolapse, hypoplasia, or dysplasia 1
• Measure pulmonary stenosis severity using peak instantaneous Doppler gradient (mild <30 mmHg, moderate 30-60 mmHg, severe >60 mmHg) 1
• Assess pulmonary regurgitation by color Doppler jet width occupying >50-65% of RVOT width, which suggests severe PR 1

Evaluate Right Ventricular Outflow Tract

• Measure RVOT dimensions at the pulmonary annulus level in parasternal short-axis or subcostal views 1, 2
• Identify subvalvular or supravalvular stenosis that may accompany valvular abnormalities 1
• Assess for infundibular hypertrophy in patients with long-standing pulmonary stenosis 1

Screen for Associated Congenital Heart Disease

• Tetralogy of Fallot (repaired or unrepaired) commonly involves pulmonary valve pathology and requires specialized follow-up 1
• Transposition of the great arteries where the spatial relationship between great vessels is abnormal 1
• Pulmonary atresia or other complex lesions affecting the RVOT 1

Clinical Management Algorithm

If Normal Pulmonary Valve Anatomy Confirmed

• No intervention required for the normal anatomic position 1
• Routine follow-up based on any other cardiac findings present on the echocardiogram 1

If Pulmonary Stenosis Detected

• Peak gradient <30 mmHg: Follow-up echocardiography every 5 years 1
• Peak gradient 30-60 mmHg: Follow-up echocardiography every 2-5 years 1
• Peak gradient >60 mmHg in asymptomatic patients: Balloon valvotomy recommended 1
• Peak gradient >50 mmHg with symptoms: Balloon valvotomy recommended 1

If Pulmonary Regurgitation Detected

• Mild PR: Clinical follow-up with serial echocardiography 1
• Severe PR with RV dilation: Consider pulmonary valve replacement, particularly in post-tetralogy of Fallot patients 1, 3

Common Pitfalls to Avoid

• Do not misinterpret normal anatomy as pathology - the pulmonary valve's superior position relative to the aortic valve is expected 1
• Do not rely solely on 2D echocardiography for complex RVOT assessment; 3D echocardiography provides superior spatial delineation 3, 2
• Do not overlook associated lesions when pulmonary valve abnormalities are present, as they frequently occur with other congenital defects 1
• Do not use transesophageal echocardiography as first-line for pulmonary valve assessment, as the valve is far from the probe and poorly visualized 1