Purpose: We evaluated four potential gallium-68 (68Ga)-labeled tracers for positron emission tomography (PET) imaging of myocardial perfusion in comparison with oxygen-15-labeled water ([15O]water) in healthy pigs. Four hexadentate salicylaldimine ligands derived from bis(3-aminopropyl)ethylenediamine (BAPEN) that showed promise in previous rat experiments were selected for this study.
Methods: Following an evaluation of myocardial blood flow with [15O]water PET, the pigs (total n=14) underwent a dynamic 90-min PET study with one of four 68Ga-labeled BAPEN derivatives (n=3-5 per tracer) either at rest or under adenosine stress. Serial arterial blood samples were collected during the imaging for the measurements of total radioactivity, radiometabolites, plasma protein binding and blood-to-plasma ratio for the 68Ga chelates. Time-activity curves of the left ventricular blood pool and myocardium were derived from PET images, and metabolite-corrected arterial input function was used for kinetic modeling. Also, ex vivo biodistribution of 68Ga radioactivity was analyzed.
Results: All four 68Ga tracers showed undesirably slow myocardial accumulation over time, but their in vivo stability, clearance from blood and the kinetics of the myocardium uptake varied. [68Ga][Ga-(sal)2BAPDMEN]1+ showed the highest myocardial uptake in PET images and tissue samples (myocardium-to-blood ratio 7.63±1.89, myocardium-to-lung ratio 3.03±0.33 and myocardium-to-liver ratio 1.80±0.82). However, there was no correlation between the myocardial perfusion measured with [15O]water and the net uptake rates or K1 values of the 68Ga chelates.
Conclusion: Our results revealed that myocardial accumulation of the 68Ga chelates proposed for myocardial perfusion imaging with PET was slow and not determined by myocardial perfusion in a large animal model. These findings suggest that the studied tracers are not suitable for clinical imaging of myocardial perfusion.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.nucmedbio.2011.11.007 | DOI Listing |
Cureus
November 2024
Cardiovascular Surgery, Sapporo Medical University, Sapporo, JPN.
The patient an 85-year-old female resided in a care facility where she maintained an independent daily activity level. She was discovered hunched over a table in her room, displaying reduced responsiveness and prompting an emergency call. Initially, her blood pressure was within 60 mmHg, and she was transported by ambulance to our hospital.
View Article and Find Full Text PDFClin Radiol
December 2024
Department of Radiology, Mie University Graduate School of Medicine, Tsu, Japan.
Aim: To investigate the relationship between each CTP parameter and that between CTP parameters and patient characteristics in patients without obstructive coronary artery disease (CAD).
Materials And Methods: Seventy-seven (28 female; 65.0±10.
Sci Rep
December 2024
Department of Cardiac Surgery, Boston Children's Hospital, 300 Longwood Ave, Boston, MA, 02115, USA.
Heart transplantation remains the ultimate treatment strategy for neonates and children with medically refractory end-stage heart failure and utilization of donors after circulatory death (DCD) can expand th donor pool. We have previously shown that mitochondrial transplantation preserves myocardial function and viability in neonatal swine DCD hearts to levels similar to that observed in donation after brain death (DBD). Herein, we sought to investigate the transcriptomic and proteomic pathways implicated in these phenotypic changes using ex situ perfused swine hearts.
View Article and Find Full Text PDFInt Immunopharmacol
December 2024
Department of Critical Care Medicine, the First Affiliated Hospital of Jinan University, Guangzhou 510632, Guangdong, China. Electronic address:
Previous studies demonstrated that dexmedetomidine (Dex) posttreatment aggravated myocardial dysfunction and reduced survival in septic mice. Yet, whether Dex elicits similar effects in septic patients as defined by Sepsis-3 remains unknown. This study sought to assess the effects of Dex-based sedation on mortality and cardiac dysfunction in septic patients defined by Sepsis-3 and to further reveal the mechanisms in septic rats.
View Article and Find Full Text PDFJ Biomed Phys Eng
December 2024
Department of Medical Physics and Engineering, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
Background: Coronary heart disease the most prevalent form of cardiovascular disease, results from the blockage of blood flow through arteries. The Myocardial Perfusion Scan (MPS) is considered a non-invasive method to assess the heart condition and provides valuable information, such as End Diastolic Volume (EDV), End Systolic Volume (ESV), Ejection Fraction (EF), Lung to Heart Ratio (LHR), and Transient Ischemic Dilatation (TID).
Objective: This study aimed to investigate changes in gated heart scan parameters to diagnose patients, who are candidates for heart surgery.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!