How does coagulative necrosis usually occur?

Coagulative necrosis typically occurs due to a sudden cutoff of blood supply to a tissue, leading to ischemia. This type of necrosis is characterized by the preservation of the basic outline of the affected tissue, even though the cells within it have died. The lack of blood supply results in a deprivation of oxygen and nutrients, which prompts metabolic changes and ultimately leads to cellular death.

The localized tissue injury is often seen in conditions such as myocardial infarction, where the heart muscle suffers due to the interruption of blood flow through the coronary arteries.

In contrast, inflammation, infection, or toxic exposure can lead to other forms of necrosis or tissue damage, but they do not primarily trigger coagulative necrosis in the same manner that ischemia does. Inflammation can accompany necrosis, while infection typically leads to liquefactive necrosis or caseous necrosis. Toxic exposure may cause cell damage or death but not specifically coagulative necrosis as a direct result of blood supply interruption.