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This research aims to investigate whether symptoms of chest pain or shortness of breath among the study population are arising due to a heart problem, particularly any reduction of blood flow to the heart muscle from blockages in the coronary blood vessels or inflammation of the heart using cardiac magnetic resonance imaging that measures the amount of blood flow during a stress state meant to simulate vigorous exercise. At present, doctors use standard magnetic resonance imaging pictures of blood flow patterns to treat heart disease. The investigators want to study if detailed blood flow measurements, in addition to the standard blood flow pattern, could diagnose heart disease more accurately and allow more doctors to understand the severity of heart disease. Early research has demonstrated that detailed blood flow measurements may be more accurate in diagnosing heart disease in some patients, but doctors need more information to know how to use these measurements.
Brain Cavernous Angiomas with Symptomatic Hemorrhage (CASH) are rare, but they exact a heavy burden of neurologic disability from recurrent bleeding, for which there is no proven therapy. This trial readiness project aims to address current critical obstacles in identifying cases at multiple sites, characterizing their relevant features, and measuring their outcome. The timing cannot be more opportune, with therapeutic targets already identified, exceptional collaboration among researchers and with the patient community, and several drugs ready to benefit from a track to clinical testing in the next five years.
This purpose of this research project is to test the diagnostic accuracy (i.e., sensitivity, specificity, positive and negative predictive value, and receiver operator curve area under the curve) of cardiac computed tomography (CT) perfusion as compared to the best non-invasive test of blood flow -- cardiac positron emission transmission (PET) perfusion imaging. The primary outcome of the study is to determine the CT perfusion technique with the highest overall diagnostic accuracy measured by the highest area under the receiver operator curve. The investigators will test 4 different CT perfusion techniques. (A) Qualitative, visual inspection of the contrast-enhanced CT images (B) Enhanced voxel distribution analysis (C) Rate of myocardial contrast enhancement analysis (D) Quantitative heart blood flow using a distributed 2-region analysis A second aim is to reduce the radiation dose needed to maintain CT perfusion diagnostic accuracy. Using the CT perfusion data, the investigators will model the minimal number of cardiac cycle radiation exposures needed to keep the diagnostic accuracy similar to the full data set. A third aim is to test the incremental diagnostic accuracy of CT angiography plus CT perfusion to identify regions of low blood flow as compared to PET perfusion alone.
This work seeks to develop, evaluate and use new MRI methods for non-invasive quantitative assessment of myocardial perfusion and perfusion reserve (MPR), and to compare with quantitative PET imaging.
This study enrolled participants with documented exercise-induced myocardial ischemia in order to evaluate whether ranolazine, when taken prior to exercise, can improve blood flow to the heart (myocardial perfusion), as assessed by exercise-induced myocardial perfusion defect size (PDS) and total perfusion deficit (TPD), using gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). This was a 2-period crossover study. The last dose of each period must have been taken 3-4 hours prior to conduct of the exercise SPECT MPI. After the research exercise SPECT MPI was performed at the end of Period 1, participants discontinued the treatment they were randomized to for that period and began the other treatment in Period 2.