This new study, published today in Neurology®, the medical journal of the American Academy of Neurology, is the most comprehensive systematic review of “hidden” brain changes in people with various heart diseases to date.

Lead author Dr. Zien Zhou, from the George Institute for Global Health, said identifying these changes could play an important role in choosing treatments for these patients.

“People with heart disease are two to three times more likely than the general population to have changes in the brain’s vasculature, but unless they have had a stroke, these patients have “They are often missed because they don’t undergo brain imaging tests,” he said.

“However, they may be more susceptible to the risk of brain hemorrhage from drugs commonly used to treat or prevent blood clots. Intracranial hemorrhage is a life-threatening complication with no proven treatment. The survival rate is less than 50 percent.”

Changes in cerebral blood vessels that can only be detected through brain imaging tests, such as silent cerebral infarction (SBI) and cerebral small vessel disease (CSVD), are known to occur more often in elderly people and people with hypertension. Although not strong enough to cause overt neurological symptoms, it can cause subtle neurological damage and increase the long-term risk of stroke and dementia.

To determine the prevalence of these hidden cerebrovascular changes in adults with atrial fibrillation, coronary artery disease, heart failure or cardiomyopathy, valvular heart disease, and patent foramen ovale (hole in the heart), George Researchers at the institute conducted a meta-analysis. Of 221 observational studies published between 1988 and 2022.

The results showed that people with heart disease:

• Approximately one-third had some form of SBI
• One quarter had a hiatus (a small cavity where nerve tissue died after a previous blockage or leak from a small artery)
• Two-thirds had white matter lesions (damage to the protective coating around nerve fibers)
• One quarter had evidence of asymptomatic microbleeds in the brain tissue.
• More than half had brain atrophy (shrinkage of the brain due to loss of neurons or connections between neurons).

The prevalence of these brain changes was generally the same between those who had had a recent stroke and those who had not, and there were no obvious sex differences in the results.

Dr. Zhou said the study also confirmed that heart disease is one of the main causes of these changes, which reflect the “vulnerability” of the brain.

“Several potential mechanisms have been proposed for the association between heart disease and hidden cerebrovascular damage, including aging, hypertension, type 2 diabetes, hyperlipidemia, smoking, and smoking. “There are common risk factors such as,” Dr. Chou said.

“The gradual decline in cardiac output in some heart patients may affect the amount of blood reaching brain tissue, contributing to vascular changes and cognitive impairment in these patients.” “There is,” he added.

“Hidden brain changes and cognitive dysfunction may also be the result of small blood clots forming in the heart and then traveling to the brain through the arterial circulation.”

Dr. Zhou said further research is needed to examine the exact causes of these brain changes and the implications for the management of these patients.

“We need to know whether performing additional MRIs in patients who are candidates for anticoagulant therapy (which is required for most cardiac patients) is cost-effective in terms of preventing unwanted side effects,” he said. There is,” he said.

“However, if we can refine the risk of cerebral thrombosis and bleeding caused by anticoagulants and use that information to select the most appropriate treatment, it may improve the safety of treatment for heart disease patients.”