Go With The Flow: Role of 4D Flow Imaging

Transcription

1 4D Flow Go With The Flow: Role of 4D Flow Imaging Niti R. Aggarwal, MD Associate Director of Cardiac MRI Assistant Professor of Medicine & Radiology University of Wisconsin Madison

2 Disclosures GE Healthcare provides research support to UW- Madison

3 1 Directional Flow MRI Magnitude z Flow, z x Phase ( ) 150 cm/s 0 cm/s 150 cm/s Physics

4 Common Clinical Applications Heart & Great Vessels (breath hold) Cardiac output Valular Regurgitation Stenoses Coarctation Shunt quantification Regurgitant volume Forward volume C. Francois, University of Wisconsin

5 3 directional Flow MRI 2D, 1 directional flow MRI 2D, 3 directional flow MRI Magnitude Magnitude Phase (L/R) Phase (S/I) Phase (S/I) Phase (A/P) Flow, z Flow, x z z Flow, z x x z z x x

6 Congenital Heart Disease Complex Glenn: 806ml/min LPA: 413ml/min RPA: 403ml/min Fontan(1): 509ml/min Fontan(2): 77mL/min 3 year old HLHS, Fontan Long labor intense scans C. Francois, University of Wisconsin

7 Congenital Heart Disease Complex SVC: 806ml/min LPA: 413ml/min RPA: 403ml/min 85% of Fontan Fontan: 509ml/min 3 year old HLHS, Fontan C. Francois, University of Wisconsin

8 2D vs 4D PC 2D PC 4D PC Coverage 2D slice 3D volume Flow sensitivity 1 directional 3 directional Scan time Short (seconds) Breath hold Free breathing Long (minutes) Free breathing Acquisition Prospective Retrospective Temporal resolution 2 TR 4 TR Image reconstruction Short Long Post processing Short Long Physics

9 4D PC MRI Source 4D Flow MR images Volumetric coverage 3 directional flow encoding: 4 acquisitions ECG gating Breathing motion in abdomen and chest Respiratory gating/triggering Mag Vy Vx Vz Flow, z SVC Aort a Velocity (m/s) 1 SVC z y x Flow, y Flow, x RPA IV C LP A Ventricl e 0 RPA IV C LPA Segmentation Visualization and Quantification

10 4D PC MRI 4D Flow MRI Data CD A/P S/I R/L Morphology Anatomy Vessel size (compliance) Cardiac anatomy Cardiac function Velocity Qualitative Velocity vectors Particle traces Streamlines 1.Put box over ROI 2.Scan Quantitative Flow PWV Shear stress Kinetic Energy P

11 SVC RPA IVC Neo aorta RV Qualitative Vector plots Streamlines Particle traces/ pathlines Velocity profiles

12 4D PC MRI 4D Flow MRI Data CD A/P S/I R/L Morphology Anatomy Vessel size (compliance) Cardiac anatomy Cardiac function Velocity Qualitative Velocity vectors Particle traces Streamlines 1.Put box over ROI 2.Scan Quantitative Flow PWV Shear stress Kinetic Energy P

13 Clinical Applications

14 Aortic Diseases 3D blood flow characteristics in aortic disease: Hemodynamics Jet flow patterns Wall sheer stress Pressure gradients Influence of valve morphology on disease progression Impact of surgical therapy on hemodynamics

15 Aortic Diseases Aneurysm M. Markl, et al. Clin Radiol. ;71(8):

16 Aortic Diseases Bicuspid AV

17 Christopher J. François, et al. J Thorac Cardiovasc Surg. ;145(5):

18 4D Flow: Wall Shear Stress Hope MD et al. Int J Cardiol. 2012;156(2):e40 42.

19 Aortic Diseases Dissection Christopher J. François, et al. J Thorac Cardiovasc Surg. ;145(5):

20 Aortic Regurgitation Aorta Forward flow: 46 ml/cycle Retrograde flow: 5 ml/cycle Net flow : 41 ml/cycle Regurg fraction: 11%

21 Mitral Valve 4ch 3ch A P

22 MPA net flow: 61 ml/cycle Aorta net flow: 56 ml/cycle Mitral regurg: 5 ml/cycle Mitral Regurgitation

23 Mitral Regurgitation

24 MPA net flow: 61 ml/cycle Aorta net flow: 56 ml/cycle Mitral regurg: 5 ml/cycle Mitral Regurgitation

25 Retrospective Valve Tracking 4ch 3ch Greater internal consistency with valve tracking than 2D PC JJM Westenberg et al. Radiology 2008;249:792. SD Roes, et al. Invest Radiol 2009;44:669. 4D Flow Images courtesy R van der Geest, PhD (Leiden)

26 Atrial Fibrillation LA stasis Mean peak vel Mean TTP Young healthy 25% 0.78 m/s 503 ms Afib 44% 0.35 m/s 422 ms Markl et al. Invest Radiol March; 51(3):

27 Ventricular Inflow and Outflow Component Direct flow Retained inflow Delayed ejection flow Residual volume Description Blood that enters and leaves the LV/RV within the analyzed cardiac cycle Blood that enters but does not leave the LV/RV within the analyzed cardiac cycle Blood that leaves but does not enter the LV/ RV within the analyzed cardiac cycle Blood that resides in the LV/RV at least two cardiac cycles Bolger et al., JCMR, 2007 Eriksson et al., JCMR, 2010 Eriksson et al., AJP, 2011 Fredriksson et al., AJP, 2011 Eriksson et al., EHJ CV Im, 2013 Images and animations courtesy: Petter Dyverfeldt and Carl Johann Carlhall, Linkoping, Sweden

28 Pulmonary Regurgitation

29 Tetralogy of Fallot SVC PA RA RV IVC C. Francois, University of Wisconsin

30 3 month old HLHS, Norwood 1 Swaddled, free breathing (no respiratory gating), 5 minute scan time

31 PAPVR with Sinus Venosus ASD C. Francois, University of Wisconsin

32 PAPVR with Sinus Venosus ASD C. Francois, University of Wisconsin

33 4D Flow: Pressure Gradients Cor triatriatum ΔP = 10mmHG C. Francois, University of Wisconsin

34 4D Flow: Kinetic Energy Healthy J Thorac Cardiovasc Surg 2015;149:1339. rtof Greater kinetic energy required to generate flow in great vessels C. Francois, University of Wisconsin

35 4D Flow in Congenital Heart Dz Simplify acquisition in complex CHD Better understanding of alterations in intracardiac flow in CHD Perform more complex hemodynamic assessments of the cardiovascular system

36 Thank you!