Persistent Left Superior Vena Cava Demonstrated by First-Pass Radionuclide Angiography

Area of Science:

• Cardiology
• Radiology
• Embryology

Background:

• Persistent left superior vena cava (PLSVC) represents a common congenital anomaly of the thoracic venous system, potentially isolated or linked with congenital heart defects.
• While various imaging modalities have documented PLSVC, its specific presentation in first-pass radionuclide angiography remains less explored.

Observation:

• A case of incidental PLSVC discovery during first-pass radionuclide angiography using left jugular vein tracer injection.
• The study observed an underestimation of the right ventricular ejection fraction due to the anomalous venous pathway.

Findings:

• First-pass radionuclide angiography can reveal PLSVC, an uncommon developmental variation.
• Tracer injection via the left jugular vein in PLSVC cases without shunting can lead to inaccurate right ventricular ejection fraction measurements.

Implications:

• Accurate assessment of right ventricular ejection fraction is crucial for managing cardiac conditions.
• Recommendations are provided for optimal tracer injection sites (right jugular or right cubital vein) to ensure precise ejection fraction calculations in patients with PLSVC.
• This finding underscores the importance of considering venous anomalies in interpreting radionuclide angiography results.