Grant: Project Grant

When looking at a heart, we can observe larger blood vessels that run on its surface and then further divide into smaller vessels as they dive into the heart wall itself, like branches on a tree. Coronary artery disease is a condition in which one of these larger vessels becomes partially obstructed. When this happens, medical doctors must decide whether to intervene. To do this, they use imaging technologies that can tell them how much smaller the artery has become. However, the important thing to look at here is not how obstructed the artery is, but rather, how much blood gets through and how far in the smaller branches it gets. However, the techniques available are limited because they cannot see the smaller branches located inside the heart wall. Ultrasound imaging uses sounds waves to make images. It is not expensive and very safe. We have developed a new way of making images that we call Myocardial Ultrasound Localization Angiography (MULA), with the objective of showing that we can image the smallest branches inside the heart wall. In order to make images using MULA, we first inject microbubbles in the bloodstream. These microbubbles stay in the blood vessels and oscillate differently than the rest of the body when subjected to an ultrasound wave, which allows us to identify them one by one in images. We acquire hundreds of thousands of images, each containing a few microbubbles, and record their exact positions for each image. We then combine all the positions obtained to generate one map containing all the blood vessels in the heart wall. MULA will provide a unique way to look at these blood vessels and better inform the medical doctor about the status of the heart perfusion.