Clinical Trials

In April 2008, a coronary catheter based imaging system, LipiScan, was cleared by the FDA for use in detecting lipid core containing containing plaques of interest (LCP). These plaques are rich in cholesterol. The way that cholesterol and other lipids deposit with the coronary artery is unique to each patient. This study is an organized attempt to observe the LCP and the variety of ways that it presents in patients as detected by this recently approved device. This information will be used for physician training and to observe the behavior of the LCP in response to no therapy and currently approved therapies. The purpose of this project is further medical knowledge of the LCP and its treatment.

Pilot study, investigates the effects of "acute" exercise on PGE levels as measured by CORUS CAD score.

Stress perfusion imaging has primarily been done with radionuclide scintigraphy or single photon emission computed tomography (SPECT) and has not reached its full clinical potential because of the poor spatial resolution of SPECT, increased expense of this procedure, patient exposure to ionizing radiation, and lack of availability. The A2A receptor agonist Regadenoson has been utilized to detect myocardial perfusion abnormalities during SPECT myocardial perfusion imaging. A 100 patient pilot study (Regadenoson Real Time Perfusion Imaging Trial, IRB #566-08-FB) demonstrated the feasibility and accuracy of real-time perfusion echocardiography (RTPE) in detecting coronary artery disease following Regadenoson bolus injection and Definity as an ultrasound contrast agent. The aim of this study is to determine whether similar feasibility and accuracy can be achieved with Optison (a Food and Drug Administration approved ultrasound contrast agent that differs slightly in microbubble size and composition) in detecting coronary artery disease (CAD) following Regadenoson bolus injection. As with the original study, sensitivity, specificity, and accuracy of perfusion and wall motion analysis to identify a coronary stenosis >50% in diameter by quantitative angiography will be analyzed.

Cardiac allograft vasculopathy (CAV) is a progressive disease of the coronary arteries in transplanted hearts which is a significant cause of morbidity and mortality. The broad objective of this research study is to advance our ability to diagnose as early as possible the presence of CAV and to non-invasively predict those patients at increased risk of CAV with novel techniques. Optical coherence tomography (OCT) is a novel intracoronary imaging technique using an optical analog of ultrasound with a resolution 10 times greater resolution than intravascular ultrasound (IVUS). Endothelial progenitor cells (EPCs) in peripheral blood have been shown to play a role in the pathogenesis of atherosclerosis and peripheral arterial tonometry is a clinical tool used to predict endothelial dysfunction (a precursor of atherosclerosis) which has been validated in non-transplant patients. Patients scheduled for routine cardiac catheterization with IVUS at the Mayo Clinic Rochester, MN that reach inclusion and exclusion criteria for the study will be approached on the day to get informed consent to perform OCT, blood sampling and peripheral endothelial function testing. The investigators aim to 1) compare the frequency and plaque type of CAV as defined with OCT versus IVUS-Virtual Histology (IVUS-VH), 2) predict the presence and severity of CAV with absolute counts of EPCs and 3) with peripheral endothelial function scores.