How does a blocked blood vessel burst cause a stroke?
When these blocks rupture, they can release material into the bloodstream that interferes with oxygen reaching the heart or brain. There is no way to determine exactly when a vascular mass will rupture.
Previous studies have relied on carotid artery samples obtained after a patient’s death or several months after a stroke or heart attack. This limits the information that can be obtained or misses events that occurred only at the time of rupture.
What Happens Inside a Blocked Blood Vessel During a Stroke?
For the first time, the present study has sequenced RNAs in vascular occlusion from patients who had experienced a stroke within two to five days. In doing so, the team created a picture of active RNAs closer to the time of break than was previously possible.
They found that the ruptured blockages increased inflammation combined with processes that can strip away part of the plaque that protects from rupture, known as the fibrous cap.
Surprisingly, the researchers found that the ruptured plaques increased markers of B-cells, a white blood cell whose role in plaque rupture was previously underappreciated.
Carotid artery occlusion is a common cause of some ischemic strokes, which occur when the blood supply to part of the brain is interrupted, preventing brain tissue from receiving the oxygen and nutrients it needs.
Because the mechanism underlying some strokes and most heart attacks is related to the same ruptured events, these findings also have implications for heart disease.
Identifying the genes that promote the thinning of these blood vessel blockages gives us new targets for treatments and diagnostics to prevent heart attacks and strokes.