Acute coronary syndrome (“ACS”) is an umbrella term that describes any condition brought on by sudden, reduced blood flow to the heart. ACS is often caused by atherosclerosis, the accumulation of plaque that can clog arteries.
While there are a number of known hereditary and lifestyle risk factors for ACS, researchers are exploring the role inflammation may play in the development of both ACS and atherosclerosis. One potential cause of inflammation may be cytomegalovirus (“CMV”) infection.
The relationship between CMV and atherosclerosis has been a subject of interest for a number of years. In a 2006 study, coronary plaque specimens from 38 patients who underwent a heart catheterization procedure were divided into an ACS group and a non-ACS group. Using special stains designed to detect CMV, researchers found the ACS group had a higher number of CMV-infected cells. The investigators concluded that CMV in the coronary plaque may be linked to the development of artery blockages.
In a more recent study, researchers examined CMV infection in 105 patients with atherosclerosis who received coronary artery bypass grafts. After adjusting for other risk factors, researchers concluded that patients with a history of ACS were more likely to test positive for CMV. Finally, in a 2012 meta-analysis of 55 prior studies, investigators concluded that CMV infection is associated with the progression of atherosclerosis, especially in Asian populations.
While these studies show that CMV may be linked to the development of atherosclerosis and ACS, the exact mechanism by which CMV affects vascular health is less well understood. Some recent research suggests that CMV and platelets may interact in a way that leads to inflammatory and angiogenic responses, which may exacerbate tissue damage and contribute to the formation of plaque in the inner lining of arteries.
By age 40, between 50% and 80% of U.S. adults will have had a CMV infection. Following the primary infection, the CMV virus typically remains dormant, but it can periodically reactivate, especially in immunocompromised persons.