106 Clinical Trials for Various Conditions
The goal of this clinical trial is to that Sodium-glucose cotransporter 2 inhibitors treatment will improve Coronary Microvascular Disease with anginal symptoms associated with non-obstructive coronary disease in women. The main questions it aims to answer are: Aim 1: Test the hypothesis that Sodium-glucose cotransporter 2 inhibitors treatment improves coronary microvascular disease in women with no evidence of epicardial obstructive coronary artery disease. Aim 2: Test the hypothesis that Sodium-glucose cotransporter 2 inhibitors treatment improves angina symptoms and other quality of life measurements associated with the improvement of CFR. AIM 3: Identify the effect of Sodium-glucose cotransporter 2 inhibition on inflammation pathways and markers of systemic Research will compare Dapagliflozin to placebo Participants will: * Take study drug or placebo for 12 weeks * Stress Cardiac magnetic resonance imaging * 12 lead electrocardiograms * Complete questionnaires
A single center, phase 0/1 clinical imaging study designed to assess the role of \[68Ga\]Galmydar PET/CT imaging in human subjects.
There is limited information on what causes injury to the heart in individuals with Sickle Cell Disease (SCD). Researchers in this study want to see if decreased blood flow to the heart during stress could be causing the heart damage seen in SCD patients. They also want to test people who don't have SCD to see if their hearts react the same way under stress. Primary Objective * To estimate the coronary flow reserve (CFR) (also referred to as myocardial perfusion reserve), as measured by PET stress-rest myocardial perfusion imaging, in SCD patients with and without diastolic dysfunction, and healthy controls. Secondary Objectives * To investigate the relationship between decreased CFR (quantified with PET stress- rest myocardial perfusion imaging) and presence of abnormal diastolic parameters
This study is a single center, early phase 1 clinical imaging study designed to assess the dosimetry of 68Ga-Galmydar for PET/CT imaging.
Background: Heart failure (HF) is a public health burden. Studies have shown a link between inflammation, myocardial dysfunction, and HF. Researchers want to use psoriasis as a disease model of chronic inflammation to further study the link between inflammation and myocardial dysfunction. Objective: To learn if chronic inflammation affects the heart and if taking a biological medicine for chronic inflammation helps improve how the heart works. Eligibility: Adults ages 18 and older who have moderate to severe psoriasis, and healthy adult volunteers. Design: Participants will be screened with a medical history. They may take a pregnancy test. Healthy volunteers will have 1 visit. Those with psoriasis will have a second visit 1 year later. Participants may give blood samples. They may have a heart function test. They may have a heart imaging test, and may get a contrast agent. If so, it will be injected into a vein. Participants may have positron emission tomography/computed tomography tests. They will lie on their back on a padded table with their arms straight overhead. They may get radioactive drugs through an intravenous (IV) catheter. They will get stress medicines through the IV. These drugs mimic exercise and increase blood flow through the heart. Participants may have cardiac magnetic resonance imaging. The scanner is a large tube. Participants will lie on a table that slides in and out of the tube. They will get gadolinium contrast in a vein to improve the pictures. They may get stress medicines. Coils will be used to help make the pictures. Participation for healthy volunteers will last 1-2 days. Participation for those with psoriasis will last 14 months. ...
This study is being done to find out the normal amount of blood within the heart muscle and the variations in this blood flow between a cardiac MRI and TTE.
The overall goal of this project is to compare the absolute quantification of myocardial perfusion done by using CT myocardial perfusion imaging (CT-MPI) and the coronary flow measured by using CT Fractional Flow Reserve analysis (CT-FFR) to the gold standard represented by PET myocardial perfusion imaging (PET-MPI).
The overall goal of this study is to investigate the signal intensity and relaxation rate characteristics of gadoterate meglumine (Dotarem, Guerbet, USA) enhanced myocardium during rest and stress perfusion cardiovascular magnetic resonance (CMR) compared to gadobutrol (Gadavist) to prove that Dotarem provides constantly high myocardial relaxation necessary for accurate quantitative perfusion evaluation. The purpose of this study is to compare two types of contrast that patients receive during cardiac MRI scans to visualize the blood flow in the cardiac muscle. Both contrasts are used in standard of care procedures, and the one administered for each patient will be randomly selected. The length of the MRI study all procedures are the same as the clinically indicated scan.
Coronary artery computed tomographic angiography (CTA) is a widely used, highly accurate technique for the detection of coronary artery disease (CAD), with sensitivity and negative predictive values of over 90% (1-4). Patients with normal CTA findings have an excellent prognosis and do not require further testing for CAD (5). However, like invasive coronary angiography (QCA), CTA is an anatomic test and, unless lesions are very severe (\>90% stenosis), cannot reliably predict the impairment of flow (functional significance) of intermediate grade stenoses. For this reason, in approximately 15-25% of patients, additional functional testing may be required after CTA, usually in the form of stress testing (6-8). Stress testing is commonly done by exercise or pharmacologic stress with electrocardiographic monitoring and often, imaging of myocardial perfusion by nuclear scintigraphy (MPI) or detection of abnormal contraction by echocardiography. This requires a separate procedure, entailing time, expense and limited risk. Furthermore, in patients with previously known CAD, CTA alone is not an adequate test, because in most cases there are multiple lesions that are possible sources of ischemia. Over the last 10 years, these investigators and others around the world have developed a method of imaging myocardial perfusion by CT (CTP). This test is an adjunct to the usual Cardiac Computed Tomography Angiography (CCTA) procedure and can be done immediately thereafter, using conventional pharmacologic stress agents. It has demonstrated accuracy in many single center trials, and in this large multicenter study, the CORE320 trial (9,10) which showed a high accuracy in predicting the combined results of QCA plus MPI testing and a second multicenter trial established non-inferiority of myocardial CTP compared with nuclear stress testing (11,12). Additionally, this investigator group has published a direct comparison of diagnostic performance of myocardial CTP imaging and SPECT myocardial perfusion imaging and demonstrated superior diagnostic performance of CTP imaging compared with SPECT for the diagnosis of significant disease on invasive angiography (13). CTP images can be acquired with two different approaches: static or dynamic. In the CORE320 study, the CTP protocol used static acquisition method. The static CTP method, samples a snapshot of the iodine distribution in the blood pool and the myocardium over a short period of time, targeting either the upslope or the peak of contrast bolus. The notion behind this is that, at the upslope of the contrast, the difference in attenuation value of the ischemic and remote myocardium is at the maximum which enables for qualitative and semi-quantitative assessment of myocardial perfusion defects. The static CTP, however, does not allow for direct quantification of the myocardial blood flow (MBF). One of the drawbacks of static CTP lies in the acquirement of only one sample of data and the possibility of mistiming of the contrast bolus that results in poor contrast-to-tissue ratios by missing the peak attenuation (14). Output and flow rate of the contrast material may affect bolus timing. In addition, the acquisition of data from sequential heartbeats affects the attenuation gradient and may result in a heterogeneous iodine distribution, mimicking perfusion defects (15). Furthermore, the static CTP is limited in detection of balanced ischemia, where the perfusion of the entire myocardium is impaired and therefore there is no reference remote myocardium for comparison for semi-quantitative or qualitative static methods of CTP interpretation. Dynamic CT perfusion imaging uses serial imaging over time to record the kinetics of iodinated contrast in the arterial blood pool and myocardium. This technique allows for multiple sampling of the myocardium and the blood pool and creating time attenuation curves (TAC) by measuring the change in CT attenuation over time. Mathematical modelling of TACs permits for direct quantification of MBF. Despite its advantages, the use of dynamic CTP were limited in the past. A high temporal resolution and high number of detectors are required for dynamic CTP to allow for entire myocardial coverage, and in order to obtain multiple consecutive images at high heart rates(16,17). But the main challenge of dynamic CTP acquisition was the high radiation dose associated with this technique. Nevertheless, with the introduction of the cutting-edge 320 detector CT scanning systems with fast gantry rotation the issue of the cardiac coverage is eliminated(17). The second-generation 320-row scanners also permit the quantification of the MBF with dynamic CTP acquisition with relatively low-dose of radiation(18,19). In this study the investigators aim to evaluate the feasibility, safety and accuracy of the low-radiation dose dynamic myocardial CT perfusion compared to static CTP approach to detect hemodynamically significant coronary artery disease.
We propose a single-scan two-injection myocardial perfusion imaging protocol using ammonia. Subjects will undergo single-scan two-injection imaging as well as regular stress single-scan single-injection protocol and the myocardial blood flow of both techniques will be compared.
This is a cross-sectional pilot study. The investigators seek to obtain early information pertaining to the relationship between measurements of myocardial perfusion reserve and myocardial fibrosis after receipt of Anthracycline-based chemotherapy (≥2 years prior).
This study is being done to find out if and how much the use of RTMPE improves a provider's confidence in the diagnosis they assign. This is important because the use of RTMPE may decrease the need for any additional invasive testing.
Is real-time myocardial perfusion echocardiography (RTMPE) a feasible and effective non-invasive method to detect significant Coronary Allograft Vasculopathy in pediatric and adult cardiac transplant recipients? Will perfusion deficits correlate with significant coronary artery stenosis identified by standard stress echocardiography and Invasive Coronary Angiography (ICA), and identify diffuse small vessel disease more effectively than current non-invasive techniques?
This is a study of the perfusion of the myocardium in adults with specific forms of repaired congenital heart disease using established cardiac MRI techniques and correlating perfusion with clinical outcomes.
The aim of this study is to assess whether myocardial perfusion reserve, measured during routine clinically ordered regadenoson stress cardiac magnetic resonance (CMR) has prognostic value in predicting adverse cardiovascular events. Myocardial perfusion reserve will be measured with CMR by assessing blood flow through the coronary-sinus - the primary vein in the heart.
This study will test the hypothesis that the anti-gravity treadmill can be safely used in stress nuclear myocardial perfusion imaging in patients unable to perform conventional treadmill exercise. This will be foundational evidence on which to consider a larger clinical trial to show that the anti-gravity treadmill improves diagnostic specificity across all cardiovascular stress testing modalities including treadmill-alone, exercise stress echocardiogram, exercise SPECT as well as having implications for cardiac PET and MRI in the future.
E-cigarettes deliver nicotine by creating an aerosol of ultrafine particles. Many questions remain about the size and composition and especially about the potential toxicity of these particles. Thus, a key unanswered question-and the research question proposed-is whether e-cigarette aerosol triggers the same acute impairment in coronary microvessel function as does conventional cigarette smoke, which delivers a very well-defined exposure to fine particles and many fold greater exposure to toxic (combustion) products including volatile organic compounds (such as acrolein) that have been implicated in the pathogenesis of tobacco-related coronary disease. Because the effects of nicotine on the human coronary microcirculation remain incompletely defined-with multiple potential vasodilator and vasoconstrictor actions each of which may vary by dose-we will determine the comparative effects of conventional cigarette smoke against e-cigarette aerosol with no nicotine, with low-dose nicotine, and with high-dose nicotine.
Unlike heart failure with reduced ejection fraction (HFrEF) where several medicines and devices have been demonstrated to reduce mortality, no such therapies have been identified in HFpEF. This may be in part due to incomplete understanding of the underlying mechanisms of HFpEF. Recently, impaired myocardial blood flow, reduced myocardial energy utilization, and increased myocardial fibrosis have been postulated to play important pathophysiologic roles in HFpEF. The investigators and others have demonstrated that HFrEF may be associated with altered myocardial energy utilization and "energy starvation." However, there are limited data regarding "energy starvation" in HFpEF and the relationships between myocardial blood flow, energy utilization, and fibrosis in HFpEF are largely unknown. Therefore, the purposes of this study are to use non-invasive cardiac imaging techniques to describe cardiac structure, function, blood flow, energetics, and fibrosis, and the relationships between these in order to better understand underlying mechanisms in HFpEF.
The primary objective of this proposal is to show the efficacy of contrast enhanced ultrasonography in detecting heart transplant rejection in humans. The secondary objective is to demonstrate the efficacy of this technique in generating data which allow for the assessment of short and long term outcomes.
BFPET will be evaluated as a diagnostic PET agent for assessing myocardial perfusion in subjects with known or suspected coronary artery disease (CAD) as compared to standard nuclear myocardial perfusion imaging (MPI). The safety of BFPET will be evaluated in known or suspected CAD subjects.
This is a pilot study in a patient population with suspected coronary artery disease (CAD) as defined by the presence of a prior abnormal nuclear (PET/SPECT) myocardial perfusion scan. In this study design, PET/SPECT will serve as the comparative standard for presence of myocardial ischemia. We intend to determine the accuracy of an improved magnetic resonance imaging (MRI) technique for detection of myocardial ischemia in subjects with suspected CAD. This is not a study to specifically evaluate the efficacy or safety of the drugs but rather the diagnostic performance of the improved cardiac MRI procedure.
The purpose of this study is to evaluate the consistency of quantitative peak stress myocardial blood flow and myocardial blood flow reserve following a 10 second, 1 minute, 2 minute or 4 minute delay in beginning the rubidium-82 infusion post-Lexiscan (regadenoson) injection. It is anticipated that there will be no or minimal difference between the four delay times.
The objective for this pilot study is to develop an optimized, clinically usable myocardial PET-MR perfusion protocol and to determine which of all data potentially available should be acquired for a clinical myocardial perfusion examination. Hypothesis: The hypothesis is that high resolution, high sensitivity DCE MRI could replace the rest PET myocardial perfusion imaging, significantly decreasing examination time and patient radiation dose while maintaining the comprehensive reference-quality PET myocardial stress perfusion coverage. The primary outcome will be comparison of diagnostic accuracy of each combination of imaging to detect clinically significant coronary artery stenosis (≥70% diameter stenosis).
The goal of this study is to use MCE (myocardial contrast/perfusion echocardiography) to study and compare short/long term change of myocardial perfusion abnormality and cardiac outcome in diabetic patients after nonfatal MI (heart attack), who are treated with different glucose control agents.
The current protocol for myocardial perfusion imaging (MPI) entails imaging within 30-45 minutes after radiotracer injection, for both rest and stress studies. We hypothesize that early imaging 10 minutes after radiotracer injection provides high image quality and diagnostic accuracy comparable to 30-45 minutes MPI.
The investigators developed a modified regadenoson nuclear stress test of the heart that incorporates an aminophylline injection following regadenoson (The ASSUAGE protocol). The modified (ASSUAGE) protocol has been associated with fewer side effects and was better tolerated by patients. This study will investigate whether the modified regadenoson stress protocol (ASSUAGE) produces blood flow pattern to the heart similar to that of a standard regadenoson stress protocol. In proven to be the case, the ASSUAGE protocol has the potential to be used on a wide scale instead of the current standard protocol.
Background: - People with congenital heart disease may develop heart failure earlier that those who do not have the disease. One theory to explain this is that the heart s own blood supply may be different in people with congenital heart disease. Problems with this blood supply can severely damage the heart. This damage can be studied with a heart imaging test called a cardiac magnetic resonance imaging (MRI) scan. Researchers want to use this type of scan to look at the blood supply to the heart in people with congenital heart disease. Objectives: - To learn more about the blood supply to the heart in people with congenital heart disease. Eligibility: - Individuals at least 18 years of age who have heart defects caused by congenital heart disease. Design: * Participants will be screened with a physical exam and medical history. Blood and urine samples will be collected. * Participants will have a cardiac MRI scan to look at the blood flow to the heart. * Participants will also have a heart stress test to measure heart function during exercise. * Other imaging studies of the heart may be performed to collect more information on heart function.
The purpose of this study is to demonstrate that the strength of agreement between single photon emission computed tomography (SPECT) imaging with regadenoson following inadequate exercise stress testing and SPECT imaging with regadenoson alone is not inferior to the strength of agreement between two sequential regadenoson SPECT images without exercise.
The physician would like to see if nuclear cardiac stress tests can predict cardiac health. For example, if a patient has an abnormal stress test, is he or she more likely to have cardiac problems in the future?
The routine administration of 75 mg of intravenous aminophylline in patients with severe chronic kidney disease undergoing a nuclear stress test with regadenoson (Lexiscan®) can reduce or eliminate the incidence of diarrhea and other side effects related to regadenoson.