The impact of water exchange on estimates of myocardial extracellular volume calculated using contrast enhanced T 1 measurements: A preliminary analysis in patients with severe aortic stenosis.

Autor: Sharrack N; Biomedical Imaging, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK., Biglands JD; Biomedical Imaging, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK.; Department of Medical Physics & Engineering, Leeds Teaching Hospitals NHS Trust, Leeds, UK., Broadbent DA; Biomedical Imaging, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK.; Department of Medical Physics & Engineering, Leeds Teaching Hospitals NHS Trust, Leeds, UK., Kellman P; National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA., Chow K; Cardiovascular MR R&D, Siemens Medical Solutions USA, Inc., Chicago, Illinois, USA., Greenwood JP; Biomedical Imaging, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK., Levelt E; Biomedical Imaging, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK., Plein S; Biomedical Imaging, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK., Buckley DL; Biomedical Imaging, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK.
Jazyk: angličtina
Zdroj: Magnetic resonance in medicine [Magn Reson Med] 2024 Apr; Vol. 91 (4), pp. 1637-1644. Date of Electronic Publication: 2023 Dec 01.
DOI: 10.1002/mrm.29956
Abstrakt: Purpose: Guidelines recommend measuring myocardial extracellular volume (ECV) using T 1 -mapping before and 10-30 min after contrast agent administration. Data are then analyzed using a linear model (LM), which assumes fast water exchange (WX) between the ECV and cardiomyocytes. We investigated whether limited WX influences ECV measurements in patients with severe aortic stenosis (AS).
Methods: Twenty-five patients with severe AS and 5 healthy controls were recruited. T 1 measurements were made on a 3 T Siemens system using a multiparametric saturation-recovery single-shot acquisition (a) before contrast; (b) 4 min post 0.05 mmol/kg gadobutrol; and (c) 4 min, (d) 10 min, and (e) 30 min after an additional gadobutrol dose (0.1 mmol/kg). Three LM-based ECV estimates, made using paired T 1 measurements (a and b), (a and d), and (a and e), were compared to ECV estimates made using all 5 T 1 measurements and a two-site exchange model (2SXM) accounting for WX.
Results: Median (range) ECV estimated using the 2SXM model was 25% (21%-39%) for patients and 26% (22%-29%) for controls. ECV estimated in patients using the LM at 10 min following a cumulative contrast dose of 0.15 mmol/kg was 21% (17%-32%) and increased significantly to 22% (19%-35%) at 30 min (p = 0.0001). ECV estimated using the LM was highest following low dose gadobutrol, 25% (19%-38%).
Conclusion: Current guidelines on contrast agent dose for ECV measurements may lead to underestimated ECV in patients with severe AS because of limited WX. Use of a lower contrast agent dose may mitigate this effect.
(© 2023 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.)
Databáze: MEDLINE
Externí odkaz: