Assessment of Translesional Markers and Metabolomics

Blockages in the blood vessels of the heart are the main cause of chest pain, heart attacks, and sudden death. A cardiac catheterization, or injecting x-ray dye into the blood vessels of the heart and taking pictures, is currently the best way of assessing these blockages. This procedure, however, does not allow us to know what is happening inside the blockages. Some blockages have a higher risk of "rupturing" and completely blocking of the blood vessel while others are at low risk for doing this. Blood levels of different substances produced by the body have been shown to be associated with a higher risk of having chest pain, a heart attack, or sudden death. There is also evidence from studies in animals and tissues taken from humans during surgery that some of these substances are made in the blockages themselves. We would like to investigate whether a number of these substances are made in the blockages and released into the bloodstream. We will do this by taking one tablespoon samples of blood upstream and downstream of the blockages in the blood vessels of the heart. The samples will be obtained by using a very thin catheter, or plastic tubing, that is about 1/3 the size of the blood vessels of the heart. We will take samples from the tightest blockage found as well as another, less tight, blockage and compare the two. We will also sample blood from the tightest blockage after it is opened by doing an angioplasty. Finally, we will also take pictures of the blockages studied using a very small ultrasound camera inserted into the blood vessel. We will compare the levels of the substances measured with the features we see on the pictures. We hope to learn if some or all of the substances measured can identify which blockages are more at risk for rupturing and causing heart attacks and sudden death. All patients who are entered into this study will already be having an angioplasty done. The procedures needed for the study (sampling of blood and taking pictures with an ultrasound) are already often, though not always, used in patients undergoing an angioplasty.