Heart

PET can measure blood flow to the heart muscle, helping detect areas with reduced blood flow due to coronary artery disease (CAD). It can also assess whether heart muscle areas affected by previous heart attacks are still alive and could benefit from procedures like angioplasty or bypass surgery.

Rubidium-82 (82Rb) is a radioactive isotope widely used for cardiac PET imaging. It is used to measure myocardial perfusion, helping to detect areas of reduced blood flow (ischemia) due to CAD. However, it is limited by a short half-life (75 seconds) and high-energy positrons, resulting in noisy, low-resolution dynamic frames, and thus inaccurate and biased quantification. We are working on noise-aware dynamic image denoising positron range correction for ⁸²Rb cardiac PET imaging.

Investigator: Chi Liu

Heart moves due to breathing and beating, causing image blurring and degraded diagnosis. Motion induced cardiac perfusion defect often result in unnecessary invasive procedures of cardiac catheterization. We have developed advanced motion correction strategies to tackle the motion challenge and successfully made clinical impact for each individual patient.

Investigator: Chi Liu

Single Photon Emission Computed Tomography (SPECT) also plays a critical role in the diagnosis and management of CAD. We are developing various deep-learning methods and investigating approaches to generate CT-like attenuation maps without CT to improve quantification without additional radiation dose, improve image resolution by increasing angular sampling, and reduce injection dose while maintaining image quality.

Investigator: Chi Liu

We have developed an approach for non-invasive mitochondrial membrane potential mapping in the heart with ¹⁸F-TPP⁺ PET. Mitochondrial dysfunction plays a key role in several cardiac diseases, such as heart failure, ischemia-reperfusion injury, or chemotherapy-induced cardiotoxicity. Our approach allows for the first time the non-invasive assessment of mitochondrial membrane potential, which can enable earlier detection of those diseases, being essential for timely intervention, as well as evaluation of treatment. The method was first assessed in preclinical studies and has more recently been translated into first-in-human studies.

Investigators: Georges El Fakhri, Felicitas Bijari

Cardiac sarcoidosis (CS) is a systematic inflammatory disorder, making it an excellent target for ¹⁸F-FDG PET imaging. Typically, standardized uptake value (SUV), a semiquantitative measure, is used to interpret the FDG PET images. However, its accuracy suffers from sensitivity to postinjection scan time and the tracer concentration in plasma. The net uptake rate constant (K_i) obtained from dynamic imaging is considered the gold standard for quantifying FDG PET images but requires a long imaging time. We are developing an approach to generate parametric K_i images for FDG PET using two 5-min scans with a population-based input function.

Investigator: Chi Liu

We are investigating the narrowing of blood vessels in peripheral artery disease (PAD) and its associated risks, such as amputation, cardiac arrest, and mortality. By focusing on the role of microvasculature health in PAD development and outcomes, we aim to improve understanding and management of the disease. Our research includes employing imaging modalities such as ultrasound, MRI, CT, PET, and SPECT for detecting microvasculature disease.

Investigator: Albert Sinusas

Myocardial infarction (MI) remains a leading cause of morbidity and mortality in the Western world and often leads to left ventricular remodeling and heart failure. The local intramyocardial delivery of biomaterials to the MI region and/or peri-infarct border zone has been shown to reduce post-MI remodeling in animal models. We have demonstrated in porcine models of reperfused and non-reperfused MI that local delivery of hydrogels to the MI region by minimally invasive surgery with and without the local release of inhibitors of matrix metalloproteinases (MMPs) stabilizes hemodynamics, reduces wall stress and results in sustained improvement in regional and global function reducing post-MI remodeling in association with decrease in MMP activity and increases in integrin activation. We developed a percutaneous transthoracic approach for multi-modality image-guided intramyocardial delivery of hydrogel that alters regional mechanics by modulation of fibroblast transformation. We utilize X-ray fluoroscopy, multi-detector computed tomography (MDCT), cone beam CT (CBCT), transesophageal echocardiography (TEE), and intracardiac echocardiography (ICE).

Investigator: Albert Sinusas

Technetium pyrophosphate (^99mTc-PYP) is a bone imaging tracer used to diagnose acute cardiac injury and transthyretin amyloidosis. Using multi-modality imaging, we have demonstrated that CT enhancement following myocardial infarction correlates with patterns of ^99mTc-PYP uptake and calcific deposits within the infarcted region.

Investigator: Albert Sinusas

Abnormal heart metabolism is often seen in cardiovascular diseases and can be detected using Deuterium Metabolic Imaging (DMI). DMI tracks the intake of a special type of glucose and its conversion into water, lactate, and glutamate in the body. We have adapted a multi-echo bSSFP method to 3T and were able to successfully differentiate three target substances and showed higher SNR than other methods.

Magn Reson Med. 2021 Nov;86(5):2604-2617. doi: 10.1002/mrm.28906

Investigator: Dana Peters

We developed a two-dimensional phase contrast (PC) acquisition with balanced steady-state free precession termed bSSFP-PC. This method has many useful applications in the heart.

J Cardiovasc Magn Reson. 2024 Winter;26(2):101098. doi: 10.1016/j.jocmr.2024.101098

Investigator: Dana Peters

We develop novel tracers and molecular imaging approaches for detecting tissue remodeling, fibrosis, and inflammation, focusing on cardiovascular and pulmonary diseases such as aortic aneurysms, atherosclerosis, calcific aortic valve disease, lung fibrosis, and granulomatous lung disease. Our portfolio of tracers includes several matrix metalloproteinase (MMP)-targeting tracers to image tissue remodeling and a family of collagen hybridizing tracers to image collagen remodeling in fibrosis. Clinical translation is a primary goal of our research, exemplified by our lead pan-MMP tracer, 64Cu-RYM2, which, following preclinical studies in murine models of aortic aneurysm, is undergoing first-in-human studies. In parallel, we use molecular imaging to advance mechanistic vascular and valvular biology studies and identify new therapies.

Investigator: Mehran Sadeghi

Uncontrolled blood pressure is a major risk factor for heart disease and stroke, leading causes of death. Many emergencies arise from adverse health behaviors or uncontrolled risk factors, and underinsured patients often lack access to care outside the Emergency Department (ED). Emergency care offers a chance to positively impact public health. We are exploring the use of point-of-care ultrasound (POCUS) in the ED to detect left ventricular hypertrophy (LVH), as a marker of chronic hypertension-related organ damage. This initiative aims to distinguish true hypertension from temporary blood pressure spikes due to stress or pain. By identifying undiagnosed LVH in ED patients with persistently high blood pressure, the study evaluates whether targeted counseling and quick referrals improve follow-up care and early treatment. Additionally, the project investigates the potential of artificial intelligence to enhance automated LVH detection and guide future public health efforts to reduce cardiovascular risk.

Investigator: Cristiana Baloescu