An isolated beating pig heart platform for a comprehensive evaluation of intracardiac blood flow with 4D flow MRI: a feasibility study

Figures

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  Fig. 1. Experimental setup of the MRI-compatible beating pig heart platform. a Experimental setup of the MRI-compatible PhysioHeartTM platform (LifeTec, Eindhoven, The Netherlands). The heart was connected to a preload and afterload system. The venous blood (purple) was heated and oxygenated outside the MRI room and pumped back to the experiment afterwards (red). The dotted lines indicate (1) coronary perfusion during the Langendorff mode and (2) the cross clamping of the aorta and the pulmonary vein. Ao Aorta, LA Left atrium, LV Left ventricle, PA Pulmonary artery, PV Pulmonary vein, RV Right ventricle. b The heart during Langendorff perfusion, attached to the aortic cannula and the pulmonary vein cannula. c The resuscitated, beating pig heart installed in the platform between the two coils on the patient bed before scanning. d The heating device and oxygenator outside the MRI room. e Setup during the scan, with two tubes leading to the MRI operator room

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  Fig. 2. Velocity vector plots of one representative heart and aortic flow curves for all five hearts. a Anatomical reference of the heart before the experiment. b Vector plots of intracardiac flow in the ejection phase. c Vortex formation and coronary filling in the aortic root of the heart during diastole. For better visualisation of intracardiac flow, d shows the vector plots of the segmented LV at end-systole and e at end-diastole, where vortex formation can be observed. f Net flow downstream to the aortic valve for all five experiments, measured in an ROI indicated in e. Ao Aorta, LA Left atrium, LAD Left anterior descending artery, LCX Left circumflex artery, LV Left ventricle, PA Pulmonary artery, PV Pulmonary vein, ROI Region of interst, RV Right ventricle

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  Fig. 3. Velocity vector plots of all five experiments at three time points in the cardiac cycle. Vector plots for the segmented left ventricle (LV) of all five experiments during (a) systole and (b) diastole. During end-diastole (c), vortex formation could be observed in all five hearts

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  Fig. 4. Linear regression and Bland-Altman plots for stroke volume and cardiac output calculated from flow and from volumetric measurements. Comparison of the two techniques used for cardiac output (CO) and stroke volume (SV) estimation using Bland-Altman analysis. a Linear regression and Bland-Altman plots for SV calculated from aortic flow data (SVflow) and from left ventricle (LV) volume (SVvolume). b Linear regression and Bland-Altman plots for CO calculated from aortic flow data (COflow) and from LV volume (COvolume)