Haemorrhagic Infarction and Transformation

Learning objectives

Haemorrhagic Infarction (HI)/Transformation

• Following an Ischaemic stroke there can be a form of secondary haemorrhage into the infarcted tissue and this is often termed haemorrhagic infarction or transformation.
• It is more common in embolic strokes, larger stroke and following spontaneous or therapeutically driven recanalisation with thrombolysis (especially intraarterial) and/or thrombectomy.
• Thrombectomy seems to have an increase of asymptomatic HI but symptomatic HI is unaffected. The rate seems to be higher with delayed recanalisation e.g. Alteplase after 3 hours.
• Poorly controlled hypertension is a risk and is one of the reasons to control blood pressure after thrombolysis. Severe hyperglycaemia may also be a risk.
• It tends to happen early within the first few days, but it can be as late as 2 weeks. It is often clinically silent especially as at this time there is rarely any need to do brain imaging.
• Blood is more clearly seen on MRI GRE and T2 star. Often the response is to omit antiplatelets for several days.
• If the patient presents late it can be difficult to distinguish haemorrhagic transformation from a primary intracerebral haemorrhage.
• HT is possibly due to the reopening of occluded blood vessels with flow into tissues with a damaged capillary bed due to local ischaemic necrosis.
• It is always a worry in re-establishing flow that haemorrhage will occur. However, there is a distinct difference between mild to moderate haemorrhage into already damaged brain and de novo haemorrhage into undamaged brain adding to the overall stroke burden.

REferences

• There is a radiological classification and an excellent review article .