Cholesterol crystals may cause heart problems

Heart Attacks and Strokes often occur when plaques inside the blood vessels rupture and block blood flow. Now, new research sheds light on how cholesterol crystal build-up in the plaque contributes to this process.

The researchers are hopeful that this information will ultimately lead to new treatments for Heart Attack and Stroke, according to the report in the medical journal Clinical Cardiology.

"As the cholesterol crystallizes, two things can happen," lead author Dr. George S. Abela, from Michigan State University in East Lansing, said in a statement. "If it's a big pool of cholesterol, it will expand and just tear the cap off the deposit in the arterial wall. Or the crystals, which are sharp, needle-like structures, poke their way through the membrane covering the cholesterol deposit, like nails through wood."

Previous studies investigating how plaques rupture have only provided a static image, the report indicates. To capture the dynamic process, the researchers conducted two experiments to evaluate the transformation of cholesterol from a liquid state to a solid. In particular, they were interested in whether the cholesterol crystals that form injure and disrupt the plaque.

In the first experiment, the researchers measured cholesterol crystallization in large cylinders. In the second, the effect of crystal growth on blood vessel-like membranes was examined.

During the experiments, the crystals grew dramatically in size and eventually pierced the test membranes.

"So far, treatments (to prevent heart attacks and strokes) have not been focused" on cholesterol crystallization, Abela noted. "Now, we have a target to attack with the various approaches we have. In the past, we've treated the various stages that lead to this final stage, rather than preventing or treating this final stage of the condition."

SOURCE: Clinical Cardiology, September 2005.