Looking a bit superficial to the pleura

Area of Science:

• Anatomy
• Medical Imaging
• Vascular Surgery

Background:

• The internal thoracic artery (ITA) originates from the subclavian artery, running bilaterally near the sternum with accompanying internal thoracic veins (ITV).
• Accurate identification of ITA and ITV is crucial for preventing iatrogenic injury during parasternal pericardiocentesis.
• Recognizing these vessels is also vital for evaluating the patency of ITA grafts in patients with coronary artery disease experiencing chest pain.

Purpose of the Study:

• To present a straightforward ultrasonographic method for identifying the internal thoracic artery and vein.
• To emphasize the clinical significance of recognizing these vessels in specific patient scenarios.

Main Methods:

• Utilized a linear probe along the parasternal line for grayscale imaging.
• Employed Color Doppler to differentiate pulsatile flow (ITA) from non-pulsatile flow (ITV).
• Applied Spectral Doppler to analyze flow velocity profiles, distinguishing between native and grafted arteries.

Main Results:

• Internal thoracic vessels appear as anechoic tubular structures anterior to the pleural line on grayscale ultrasound.
• Color Doppler clearly distinguishes the pulsatile arterial flow from the non-pulsatile venous flow.
• Spectral Doppler reveals characteristic high-resistance flow in native ITAs and biphasic low-resistance flow in patent ITA grafts.

Conclusions:

• The internal thoracic artery (non-grafted) and vein are routinely identifiable using parasternal ultrasonography.
• Sonographic identification is essential for guiding safe pericardiocentesis and assessing ITA graft permeability in relevant clinical contexts.