Which structure is primarily targeted by Tc sestamibi during imaging?

• A. Bone tissue
• B. Heart tissue
• C. Adrenal glands
• D. Brain tissue

Answer: (B)

Tc sestamibi is primarily used in imaging the heart, particularly in myocardial perfusion studies. It is a radiopharmaceutical that is taken up by myocardial cells, making it an effective agent for assessing heart function and identifying areas of reduced blood flow or ischemia. The compound accumulates in healthy myocardial tissue more than in areas with compromised blood supply, allowing for visualization of heart function through gamma cameras.

Other structures such as bone tissue, adrenal glands, and brain tissue do not have the same affinity for Tc sestamibi, which is optimized for cardiac imaging. This specificity for heart tissue is what makes Tc sestamibi particularly valuable in diagnosing conditions such as coronary artery disease and evaluating myocardial viability.