Heart Attacks, the Brain and Bone Marrow

By Jane Farrell

People with recent heart attacks have significantly higher activity in the amygdala, the brain area involved in stress perception and emotional response, along with greater inflammation in arteries resulting from increased bone marrow activity, a hallmark of plaque build-up. But these levels are not permanent: In fact, they can all return to near-normal,  experts said.

These conclusions were contained in preliminary research presented at the American Heart Association’s Vascular Discovery: From Genes to Medicine Scientific Sessions 2020.

The meeting is a premier global exchange of the latest advances in new and emerging scientific research in arteriosclerosis, thrombosis, vascular biology, peripheral vascular disease, vascular surgery and functional genomics.

“The results of this study advance our understanding of the interconnections among the brain, bone marrow and blood vessels, with activity of the brain emotional center closely linked to heart disease activity and inflammation of blood vessels which are spurred by inflammatory immune cells produced by the bone marrow,” said Dong Oh Kang, M.D., lead study author and clinical instructor in the cardiovascular center of Korea University Guro Hospital in Seoul, Korea.

The researchers obtained simultaneous PET and CT scans to create 3-D images of the brain, major arteries and bone marrow of 62 study participants. The study included 45 people (84% male, average age 60 years) who had a heart attack within the previous 45 days and 17 people with no heart attack history (76% male, average age 59.6 years), the control group. All participants completed widely accepted standard screening questionnaires for depression and perceived stress.

Those who had a recent heart attack had significantly higher activity in the amygdala region of the brain, which is responsible for stress perception and emotional response.

The participants who had a recent heart attack also had increased inflammation in the aorta and carotid artery (neck), which supplies blood to the brain, and increased bone marrow activity, indicating active production of inflammatory cells.

In both groups, those who reported feeling more depressed or stressed on psychological questionnaires showed higher activity in the amygdala.

Butrain emotional activity and inflammation can change over time. After six months, the 10 heart attack patients who underwent follow-up imaging had near-normal PET and CT scans.

“Amygdala activity has previously been reported to be stable over time, however, the changes seen in our study suggest the possibility that stress reduction techniques may lower brain emotional activity and potentially reduce inflammation in arteries and the production of inflammatory cells, thus, potentially modifying the course of heart disease. This could become an additional strategy to prevent a second heart attack,” Kang said.

Although the study found significant links between amygdala activity and artery inflammation, intervention studies are needed to investigate the possible benefits of modifying brain emotional activity on atherosclerosis. Kang also noted more research is needed to identify the most effective stress relief treatments.