The aorta is a large blood vessel through which blood flows from the heart to the rest of the circulatory system. And, for this delicate but vital process to happen normally, the aortic valve plays an essential role. This valve opens and closes both to allow blood to flow out and to prevent it from returning to the heart.
Calcific aortic valve disease (CAVD) is a pathology of the heart in which either the valve does not close and open well, or its narrowness prevents blood from flowing as it should. This process can lead to a more serious disease: stenosis, a severe narrowing of the aortic valve that reduces blood flow to body tissues and weakens the heart.
Today, the only treatment for stenosis is valve replacement, which generally requires risky and expensive open-heart surgery. But thanks to an investigation by the Arlington Agricultural Research Station of the University of Wisconsin-Madison, a possible treatment route has been opened that would prevent the disease and thus avoid such intervention.
The researchers analyzed, for the first time, the set of events that can trigger a stenosis.
“With a better understanding of how the disease progresses from early to later stages, we will eventually be able to stop CAVD and avoid valve replacement surgery, ” the researchers detail in the study, published in the journal Proceedings of the National Academy of Sciences .
The research was carried out in pig models , since the heart of animals as small as mice is very different from that of humans.
The pig hearts provided a snapshot of CAVD in its early stages, which is difficult to capture in humans, showing that the disease begins with the accumulation of certain sugar molecules called glycosaminoglycans (GAGs) in valve tissue.
By modifying the amount of GAG these valve cells were exposed to, they observed surprising results that defied previous assumptions.
The more glycosaminoglycans they received, the less inflammatory factors were produced in the cells. GAGs directly increased a chemical needed to grow new blood vessels. In addition, the GAGs trapped low-density lipoprotein (LDL) molecules.
A new treatment route
The next step would be to develop drugs that can prevent CAVD from progressing to stenosis by making glycosaminoglycans less likely to bind to these LDL lipoproteins.
By preventing stenosis from occurring, we would not only end this heart disease, but we could also avoid risky and complex heart surgery.
References: The study was funded by the National Institutes of Health and the American Heart Association.
