Thin Walled Microvessels In Human Coronary Atherosclerotic Plaques Show Incomplete Endothelial Junctions Relevance Of Compromised Structural Integrity For Intraplaque Microvascular Leakage

This study examined the microscopic structure of tiny blood vessels (microvessels) found within atherosclerotic plaques - the fatty buildups that narrow coronary arteries and can cause heart attacks. Using advanced imaging techniques, researchers analyzed 28 coronary arteries to understand how these small vessels contribute to plaque instability.

The researchers discovered that as plaques progress from early to advanced stages, they develop more of these microvessels. However, these vessels have serious structural problems. Unlike healthy blood vessels, the microvessels in plaques have incomplete connections between their lining cells (endothelial cells), abnormal cellular features, and compromised barriers that normally prevent leakage. This poor structural integrity allows blood components, inflammatory cells, and other substances to leak into the plaque itself.

This leakage is significant because it can cause bleeding within plaques (intraplaque hemorrhage), increased inflammation, and accumulation of cholesterol - all factors that make plaques more likely to rupture. When a plaque ruptures, it can trigger the formation of a blood clot that blocks the artery, causing a heart attack.

From a metabolic health perspective, this research helps explain one mechanism by which chronic inflammation and metabolic dysfunction contribute to cardiovascular events. In clinical practice, this knowledge supports the importance of comprehensive cardiovascular risk management, including control of inflammation, blood pressure, and metabolic factors that influence plaque development and stability, rather than focusing solely on cholesterol levels.