Systemic transit time correlates with renal cortical perfusion: a preliminary study

Abstract Funding Acknowledgements Type of funding sources: None. Introduction We sought to measure systemic transit time (STT) on MRI dynamic sequences images in patients based the recirculation time. In a subset patients, using same images, when abdominal aorta and at least part one kidney was available, we used 2-compartment filtration model approximate renal cortical plasma perfusion (RCPF). Methods This is retrospective study single site MR unit. 218 underwent standard myocardial imaging protocol 1.5 Tesla system including pulse-gated, free breathing, first-pass scan 100 phases saturation recovery turbo-FLASH pulse sequence (TR = 172 ms / TE 1.1 flip angle 5°). Motion correction applied. All were injected intravenously with bolus dose gadoteratemeglumine followed by 20 ml saline flush. On studied, excluded due shunts:n=5, inadequate first pass signal:n=8, fitting script did not converge solution:n=7. Circular ROIs placed RV (Right Ventricle) LV (Left Ventricle)cavities. The curves for each cavity’s signals fitted time-sliding 3 component-LogNormal function an in-house python lmfit package (Levenberg-Marquardt method) determine pulmonary times (PTT). 61 attempt RCPF undertaken. An elliptic ROI drawn follow arterial input. A spline polygon visible tissue. 14 sets rejected analysis different reasons (absence suitable image, absence motion artifact, …). Plasma measurements made model. Results studied 198 images. Our population consists 65,7% men aged 53,0±16,9 (mean± SD) 34,3% women 55,9 ± 14,1 (mean SD). Fitting experimental data very good most cases R² RV:0.981, max:0.997, min: 0.907, SD:0.014) LV: 0.994, max:0.999, 0.975, SD: 0.004). example can be seen fig. 1. STT values as follows: mean 14.3 s, SD 3.0s, max 27.1 min 8.7 s. Measures highly correlated side (Pearson’s R =0,975; p < 0,001). found significant correlation between PTT 0,521; 47 where could calculated, negative -0,578; 0,001) (fig. 2). Conclusions Systemic accurately measured scans negatively perfusion. Assessing heart usable surrogate end-organ