Can an old cortical infarct (cerebral infarction) cause seizures?

From the Guidelines

Yes, old cortical infarcts can cause seizures, and patients with a history of cortical infarction should be monitored for seizure activity and treated with antiepileptic medications if seizures occur. Post-stroke seizures are a recognized complication of cerebral infarction, particularly when the infarct involves the cerebral cortex, as noted in the Canadian Stroke Best Practice Recommendations 1. These seizures can develop months or even years after the initial stroke and are classified as post-stroke epilepsy when they occur more than one week after the infarct. The risk is highest with cortical involvement rather than subcortical or deep brain infarcts because the cerebral cortex contains highly epileptogenic tissue.

The mechanism involves the formation of gliotic scar tissue around the damaged brain area, which creates abnormal electrical activity that can trigger seizures. According to the American Heart Association 1, seizures are a possible complication of large cortical strokes and can be potentially life-threatening if not controlled. Treatment typically involves antiepileptic medications, with the specific choice depending on the patient's age, comorbidities, and potential drug interactions.

Some key points to consider in the management of post-stroke seizures include:

• New-onset seizures in admitted patients with acute stroke should be treated using appropriate short-acting medications, such as lorazepam IV, if they are not self-limiting 1.
• A single, self-limiting seizure occurring at the onset or within 24 h after an ischemic stroke should not be treated with long-term anticonvulsant medications 1.
• Patients with one or more seizures in the early or late post-stroke period should be treated as per treatment recommendations for seizures in other neurological conditions 1.
• Prophylactic use of anticonvulsant medications in patients with ischemic stroke is not recommended, as there is no evidence to support its use and some evidence to suggest possible harm 1.

Overall, the management of post-stroke seizures requires careful consideration of the individual patient's risk factors, medical history, and potential benefits and harms of treatment, with a focus on minimizing morbidity, mortality, and improving quality of life 1, 1.

From the Research

Relationship Between Old Cortical Infarct and Seizures

• An old cortical infarct, also known as a cerebral infarction, can potentially cause seizures, as evidenced by studies that have investigated the relationship between stroke and seizure occurrence 2, 3, 4, 5.
• Research has shown that the location and size of the infarct, as well as the patient's age and history of previous strokes, can influence the risk of developing seizures after a stroke 2, 3, 5.

Factors Influencing Seizure Risk

• A study published in 1996 found that patients with a large brain infarct involving the supramarginal or superior temporal gyrus had a five times increased risk of late-onset seizures 2.
• Another study published in 2012 found that a history of previous stroke was a significant risk factor for seizures in patients with a posterior circulation infarct 3.
• A 2020 study suggested that posterior circulation stroke, particularly brainstem infarction, may be an important risk factor for stroke-onset seizures 4.
• A 2023 study found that cortical involvement of a recent infarct contralateral to early focal seizures was observed in 43% of patients with early seizures, and that glucose and hemoglobin A1c levels were significantly higher in these patients 5.

Use of Antiepileptic Drugs

• A 2022 Cochrane review found that antiepileptic drugs (AEDs) were not effective in primary prophylaxis of post-stroke seizure, although there was some evidence to suggest that AEDs may be beneficial in specific subgroups of patients, such as those with anterior circulation cortical infarcts 6.
• The review concluded that there is insufficient evidence to support the routine use of AEDs for the primary and secondary prevention of seizures after stroke, and that further well-conducted studies are needed to address this important clinical problem 6.