Final answer:
Macrophages clear necrotic cells following a myocardial infarction to aid in healing and tissue repair.
Step-by-step explanation:
Macrophages play a crucial role in the immune response following a myocardial infarction (M.I), also known as a heart attack. They are responsible for clearing necrotic (dead) cells that result from the damage to heart tissue. Macrophages are recruited to the site of the M.I and begin the process of phagocytosis, where they engulf and remove the dead cells. This clearance of necrotic cells by macrophages typically occurs in the days and weeks following the M.I, as part of the healing and tissue repair process.