Pericardial Echo-Free Space: Epicardial Fat vs. Pericardial Effusion ■ Epicardial adipose tissue often appears as echo-free space mimicking pericardial effusion in echo. • Most adipose tissue distributes in atrio-ventricular or interventricular groove. • Excessive fatty infiltration tends to occur in old, obese, and diabetic patients, particularly in women. ■ differentiation of adipose tissue from fluid is based on echogenicity, texture, mobility, and location. With exception of loculated effusion, free pericardial fluid accumulates on dependent region, usually posterior of left in supine position. • Anteriorly located echo-free space is likely to be epicardial fat deposition rather than pericardial effusion. The mobility of adjacent tissue is a clue to differentiation. As adipose tissue is less mobile than pericardial fluid, the surrounding epicardial and pericardial layers move less freely in case of fatty infiltration. ■ adipose tissue is more echogenic and lobulated than fluid with homogenous echogenicity. ■CT imaging can definitely differentiate epicardial adipose tissue from fluid collection in complicated case.
NORMAL ANATOMIC VARIANTS IN THE LEFT ATRIUM ■ Dilated coronary sinus (persistent L superior vena cava) Coumadin Ridge-Raphe between L superior pulmonary vein and LAA ■ Atrial suture line (transplant) . Beam-width artifact from calcified aortic valve, AV prosthesis, etc.
