Necrosis is tissue dying, from any cause. Infarction is tissue dying specifically because its blood supply was cut off. Infarction is therefore one cause of necrosis — the dead area it leaves behind is called an infarct.
The core difference
- necrosis — the death of tissue. Says nothing about why.
- infarction — tissue death caused by obstruction of the blood supply. A specific mechanism.
Process and result
Three related words are easily muddled:
- Ischaemia — blood supply reduced but not yet fatal to the tissue. Potentially reversible.
- Infarction — the process of tissue dying because that supply was cut off.
- Infarct — the dead area itself, the noun for the resulting lesion.
Ischaemia that persists becomes infarction, which leaves an infarct. Restoring flow in time is the whole basis of emergency treatment for heart attack and stroke.
Where the terms are used
- Myocardial infarction — heart muscle. The clinical name for a heart attack.
- Cerebral infarction — brain tissue. The commoner type of stroke, as distinct from a haemorrhagic stroke, which is bleeding rather than blockage.
- Pulmonary infarction — lung tissue, usually following an embolism.
Why the distinction matters in treatment
Because the two kinds of stroke need opposite interventions. An infarction is treated by breaking up or removing a clot; a haemorrhage is treated by controlling bleeding. Giving clot-busting drugs to a haemorrhagic stroke would be actively harmful, which is why imaging comes before treatment.
Where the word comes from
Infarction is from Latin infarcire, to stuff into — the same root as farce, which originally meant stuffing, both in cookery and in the sense of comic material stuffed into a play. The medical image is of a vessel stuffed shut.
Necrosis is Greek nekros, a corpse.
This page explains the words, not your symptoms. Anything of concern is a matter for a doctor.
Frequently asked questions
What is the difference between infarction and necrosis?
Necrosis is tissue dying from any cause. Infarction is tissue dying specifically because the blood supply was obstructed.
What is an infarct?
The dead area of tissue left behind by an infarction. Infarction is the process; the infarct is the result.
Does infarction really share a root with farce?
Yes. Both come from Latin infarcire, to stuff into. Farce originally meant stuffing, in cookery and then in theatre.