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Background: Angiogenesis has increasingly been a target for imaging and treatment over the last decade. The integrin αvβ3 is highly expressed in cells during angiogenesis and are therefore a promising target for imaging. In this study, we aimed to investigate the PET tracer [68Ga]Ga-RGD as a marker of angiogenesis following MI and its ability to predict cardiac functional parameters. Methods: First, the real-time interaction between [68Ga]Ga-RGD and integrin αvβ3 was investigated using surface plasmon resonance (SPR). Second, an animal study was performed to investigate the [68Ga]Ga-RGD uptake in the infarcted area after one and four weeks following MI in a rat model (MI = 68, sham surgery = 36). Finally, the specificity of the [68Ga]Ga-RGD tracer was evaluated ex vivo using histology, autoradiography, gamma counting and flow cytometry. Results: SPR showed that [68Ga]Ga-RGD has a high affinity for integrin αvβ3, forming a strong and stable binding. PET/CT showed a significantly higher uptake of [68Ga]Ga-RGD in the infarcted area compared to sham one week (p < 0.001) and four weeks (p < 0.001) after MI. The uptake of [68Ga]Ga-RGD after one week correlated to end diastolic volume (r = 0.74, p < 0.001) and ejection fraction (r = − 0.71, p < 0.001) after four weeks. Conclusion: This study demonstrates that [68Ga]Ga-RGD has a high affinity for integrin αvβ3, which enables the evaluation of angiogenesis and remodeling. The [68Ga]Ga-RGD uptake after one week indicates that [68Ga]Ga-RGD may be used as an early predictor of cardiac functional parameters and possible development of heart failure after MI. These encouraging data supports the clinical translation and future use in MI patients. [ABSTRACT FROM AUTHOR]

Hybrid PET/MR imaging is an emerging imaging modality combining positron emission tomography (PET) and magnetic resonance imaging (MRI) in the same system. Since the introduction of clinical PET/MRI in 2011, it has had some impact (e.g., imaging the components of inflammation in myocardial infarction), but its role could be much greater. Many opportunities remain unexplored and will be highlighted in this review. The inflammatory process post-myocardial infarction has many facets at a cellular level which may affect the outcome of the patient, specifically the effects on adverse left ventricular remodeling, and ultimately prognosis. The goal of inflammation imaging is to track the process non-invasively and quantitatively to determine the best therapeutic options for intervention and to monitor those therapies. While PET and MRI, acquired separately, can image aspects of inflammation, hybrid PET/MRI has the potential to advance imaging of myocardial inflammation. This review contains a description of hybrid PET/MRI, its application to inflammation imaging in myocardial infarction and the challenges, constraints, and opportunities in designing data collection protocols. Finally, this review explores opportunities in PET/MRI: improved registration, partial volume correction, machine learning, new approaches in the development of PET and MRI pulse sequences, and the use of novel injection strategies. [ABSTRACT FROM AUTHOR]

Background: Depressed left ventricular ejection fraction (LVEF), LV mechanical dyssynchrony (LVMD), and prolonged QTc interval predict poor outcomes in end-stage renal disease (ESRD). Renal transplantation improves mortality in ESRD patients but the effects of transplantation on these indices remain undefined.Methods: We identified patients with myocardial perfusion imaging (MPI) before and after renal transplantation. A control group consisted of ESRD patients who underwent 2 MPIs but did not receive a transplant. Changes in LVEF, LVMD indices [phase standard deviation (SD) and bandwidth (BW)] by MPI, and electrocardiogram (ECG) indices were determined.Results: The study population consisted of 32 ESRD patients (53% male, 50 ± 11 years, 59% African American, 65% diabetic). The second MPI was performed 31 months (13-59 months) after renal transplantation. LVEF (72 ± 10% vs. 67 ± 10%, P < 0.001) but not SD (22 ± 15° vs. 22 ± 11°, P = 0.9) or BW (58 ± 35° vs. 57 ± 29°, P = 0.9) improved after transplantation. There were no changes in these indices in the control group. QTc (425 ± 30 ms vs. 447 ± 32 ms, P = <0.001) but not QRS (90 ± 21 ms vs. 90 ± 21 ms, P = 0.9) improved significantly after renal transplantation.Conclusions: LVEF and QTc improved after renal transplantation but LVMD indices and QRS did not change, which suggests that LVMD and electrical dyssynchrony may be irreversible in ESRD. [ABSTRACT FROM AUTHOR]

Current cancer therapy has led to tremendous improvements in outcomes. These therapies rely both on established therapies, such as anthracyclines and radiation, and molecularly-targeted therapies, such as tyrosine kinase inhibitors and immune modulators. Integrative care for patients with cancer must consider the potential effects of these therapies on a variety of organ systems, including the cardiovascular system. As a result, specialties such as cardio-oncology have developed to identify these effects, determine how to best monitor for these effects, and how to treat and ultimately prevent these effects while allowing the patient to receive the therapy they require for their cancer. This review provides a basis for understanding the cardiovascular effects of cancer therapies so that the most appropriate imaging modality may be selected to prevent and treat these effects. [ABSTRACT FROM AUTHOR]