Measuring myocardial blood flow with 82 rubidium using Gjedde-Patlak-Rutland graphical analysis.

Autor: Gregg S; Department of Nuclear Medicine, Royal Brompton and Harefield NHS Foundation Trust, London, UK., Keramida G; Department of Nuclear Medicine, Royal Brompton and Harefield NHS Foundation Trust, London, UK., Peters AM; Department of Nuclear Medicine, King's College Hospital NHS Foundation Trust, Denmark Hill, Brixton, London, SE5 9RS, UK. adrien.peters@nhs.net.
Jazyk: angličtina
Zdroj: Annals of nuclear medicine [Ann Nucl Med] 2021 Jul; Vol. 35 (7), pp. 777-784. Date of Electronic Publication: 2021 Jun 02.
DOI: 10.1007/s12149-021-01591-x
Abstrakt: Objective: Myocardial blood flow (MBF) is measured with 82 Rb using non-linear, least-squares computerised modelling. The study aim was to explore the feasibility of Gjedde-Patlak-Rutland (GPR) graphical analysis as a simpler method for measuring MBF.
Methods: Patients had myocardial perfusion imaging using adenosine (n = 45) or regadenoson (n = 33) for stressing. Blood 82 Rb clearance into myocytes (K 1 ) was measured from Cedar-Sinai QPET software using the modified Crone-Renkin equation of Lortie et al. (K 1  = [1-0.77 × e -B/MBF ] × MBF) to convert K 1 to MBF (ml/min/100 ml), where B (63 ml/min/100 ml) is myocardial permeability-surface area product. Using aorta or left ventricular cavity (LV) to measure arterial blood 82 Rb concentration, blood 82 Rb clearance into myocardium (Z) was measured from GPR analysis based on data acquired between 1 and 3 min post-injection. As units of K 1 and Z are, respectively, ml/min/ml intracellular space and ml/min/ml total tissue including extracellular space, myocardial extracellular fluid volume (ECV) is 1 - [Z/K 1 ]. Using Z/K 1 (see Results) to modify its index, the Lortie equation was changed to Z = (1-0.77 × [Formula: see text]e -B Z /MBF Z )*MBF Z , following which MBF Z was calculated from Z. In GPR analysis, spillover of activity from LV to myocardium conveniently 'drops out' in the intercept of the plot.
Results: Both agents increased myocardial blood flow almost equally. ECV was ~ 35 ml/100 ml at rest, increasing to ~ 40 ml/100 ml after stress. Z/K 1 , averaged between stress, rest, stressing agents and arterial ROI, was 0.62, so B Z was taken as 39 (i.e. 0.62 × 63) ml/min/100 ml. Based on LV, MBF Z (y) correlated with MBF (x): y = 0.43x + 22 ml/min/100 ml; r = 0.84; n = 156). Their respective stress/rest ratios showed a moderate correlation (r = 0.64; n = 78).
Conclusions: GPR analysis offers promise as a valid and analytically simpler technique for measuring myocardial blood flow, which, as with any clearance measured from GPR analysis, has units of ml/min/ml total tissue volume, and merits development as a polar map display.
Databáze: MEDLINE
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