Purpose: To determine how injection rate, cardiac function, and breathhold influence the arterial input function (AIF), in order to optimize the AIF in the clinical setting for quantitative myocardial perfusion cardiovascular magnetic resonance (CMR).
Materials And Methods: Gd (0.1 mmol/kg) bolus was injected at 3, 5, or 7 mL/second in 35 patients. In each cardiac cycle during the first-pass, a series of saturation recovery (SR) fast low-angle shot (FLASH) low resolution images with exponentially increasing SR delay times were acquired. Signal intensity (SI) time measurements were made from a region of interest (ROI) drawn in the ascending aorta (AA). The calculation of short T1s and thus peak Gd concentration [Gd] was performed by fitting the mean ROI SI against SR delay times.
Results: The mean peak [Gd] in the AA increased as injection rate increased from 3 mL/second (5.0 mM), to 5 mL/second (7.1 mM), to 7 mL/second (4 mM) (P < 0.0001). The peak [Gd] increased as the left ventricular stroke volume (LV SV) increased (P = 0.01). Breath holding was not found to influence peak [Gd].
Conclusion: In this study, we found that a high injection rate has advantages over lower injection speeds, although the duration of the AIF was apparently not significantly shortened by faster injection. The choice of expiration or inspiration as breathhold did not have a significant influence upon the AIF. Poor cardiac function was associated with a lower peak [Gd], indicating that first pass perfusion measurements in these patients will be suboptimal.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/jmri.20294 | DOI Listing |
N Engl J Med
January 2025
From the TIMI Study Group, Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston (C.T.R., S.M.P., R.P.G., D.A.M., J.F.K., E.L.G., S.A.M., S.D.W., M.S.S.); Anthos Therapeutics, Cambridge, MA (B.H., S.P., D.B.); the Heart Rhythm Center, Taipei Veterans General Hospital and Cardiovascular Center, Taipei, Taiwan (S.-A.C.); Taichung Veterans Hospital, Taichung, Taiwan (S.-A.C.); National Yang Ming Chiao Tung University, Hsinchu, Taiwan (S.-A.C.); National Chung Hsing University, Taichung, Taiwan (S.-A.C.); St. Michael's Hospital, Unity Health Toronto, Peter Munk Cardiac Centre, University Health Network, University of Toronto, Toronto (S.G.G.); Canadian VIGOUR Centre, University of Alberta, Edmonton, Canada (S.G.G.); the Division of Cardiology, Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea (B.J.); the Department of Cardiology, Central Hospital of Northern Pest-Military Hospital, Budapest, Hungary (R.G.K.); the Heart and Vascular Center, Semmelweis University, Budapest, Hungary (R.G.K.); the Internal Cardiology Department, St. Ann University Hospital and Masaryk University, Brno, Czech Republic (J.S.); the Department of Cardiology and Structural Heart Diseases, Medical University of Silesia, Katowice, Poland (W.W.); the Departments of Medicine and of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, Canada (J.W.); and the Thrombosis and Atherosclerosis Research Institute, Hamilton, ON, Canada (J.W.).
Background: Abelacimab is a fully human monoclonal antibody that binds to the inactive form of factor XI and blocks its activation. The safety of abelacimab as compared with a direct oral anticoagulant in patients with atrial fibrillation is unknown.
Methods: Patients with atrial fibrillation and a moderate-to-high risk of stroke were randomly assigned, in a 1:1:1 ratio, to receive subcutaneous injection of abelacimab (150 mg or 90 mg once monthly) administered in a blinded fashion or oral rivaroxaban (20 mg once daily) administered in an open-label fashion.
J Am Chem Soc
January 2025
Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States.
Li-rich cation-disordered rocksalt (DRX) materials introduce new paradigms in the design of high-capacity Li-ion battery cathode materials. However, DRX materials show strikingly sluggish kinetics due to random Li percolation with poor rate performance. Here, we demonstrate that Li stuffing into the tetrahedral sites of the Mn-based rocksalt skeleton injects a novel tetrahedron-octahedron-tetrahedron diffusion path, which acts as a low-energy-barrier hub to facilitate high-speed Li transport.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill 27599, United States.
Architecturally hindered crystallization of bottlebrush graft copolymers offers a reaction- and solvent-free pathway for creating injectable elastomers with tissue-mimetic softness. Currently, injectable materials involve solvents and chemical reactions, leading to uncontrolled swelling, leaching of unreacted moieties, and side reactions with tissue. To address this issue, bottlebrush copolymers with a poly(ethylene glycol) (PEG) amorphous block and crystallizable poly(lactic acid) (PLA) grafted chains (A--B) were synthesized, with grafted chains of controlled length arranged along the backbone at controlled spacing.
View Article and Find Full Text PDFAntib Ther
January 2025
Biologics Innovation Institute, Shanghai Jemincare Pharmaceutical Co., Ltd., Lane 535, Huanqiao Road, Pudong New Area, Shanghai 201315, China.
Background: Therapeutic antibody drugs targeting the PD-1 pathway are generally characterized by relatively low response rates and susceptibility to drug resistance during clinical application. Therefore, there is an urgent need for alternative therapeutic strategies to increase the immune response rate. Bispecific antibodies co-targeting PD-1 and PD-L1 may have greater potential to improve the efficacy of the immune checkpoint pathway.
View Article and Find Full Text PDFAm J Clin Exp Urol
December 2024
Department of Urology, People's Hospital of Tibet Autonomous Region Lhasa 850000, Tibet Autonomous Region, PR China.
Ureteral stent must be removed within a certain period, usually performed under the cystoscope. However, cystoscopic operations procedures carry risks such as urethral injury, hemorrhage, and infection. This study aimed to implement a cystoscope-free method for ureteral stent removal during the COVID-19 pandemic to mitigate the complications associated with cystoscopy, reduce the risk of cross-infection, and conserve medical resources and time.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!