Christopher Macgowan

Research Synopsis

Over the last 20 years, I have developed novel, non-invasive imaging methods to evaluate cardiovascular physiology in children, with a focus on translating these methods into clinical application. This experience has included the theoretical development, experimental validation and practical implementation of advanced magnetic resonance and ultrasound imaging methods to improve quantification of blood flow, blood oxygen saturation, tissue perfusion and vascular mechanics. Furthermore, my translation of these methods into useful clinical tools has helped to advance studies of heart disease, multiple sclerosis and at-risk pregnancies.

My recent research has focused on measurement of fetal cardiovascular anatomy and physiology. My group was the first to quantify human fetal blood flow, blood oxygenation, hematocrit and cardiac dynamics using MRI. In collaboration with clinical investigators locally and internationally, I have translated these methods to studies of human pathology including fetal congenital heart disease, fetal anemia and placental insufficiency.

In parallel to these human studies, I have collaborated with fetal physiologists to study the fetal circulation in a preclinical sheep model. Using anesthetized sheep and a volumetric, velocity-sensitive MRI method (4D Flow), we have obtained the first visualization of the complex streaming of oxygenated blood as it leaves the umbilical cord and preferentially passes through the fetal heart to supply the fetal myocardium and brain. Using this same approach, we have also visualized and quantified the fetal hepatic circulation. Understanding how the fetal circulation is disrupted in preclinical models of diseases of the placenta or fetal cardiovascular system will improve our understanding and management of at-risk human pregnancies.

Recent Publications

1. Goolaub DS, Xu J, Schrauben EM, Marini D, Kingdom J, Sled GJ, Seed M, Macgowan CK. Volumetric Fetal Flow Imaging with Magnetic Resonance Imaging IEEE Trans. Med. Imag. 41(10): 2941-2952 (2022) doi: 10.1109/TMI.2022.3176814
2. Goolaub DS, Xu J, Schrauben EM, Sun L, Roy CW, Marini D, Seed M, Macgowan CK. Fetal Flow Quantification in Great Vessels Using Motion‐Corrected Radial Phase Contrast MRI: Comparison With Cartesian J. Magn. Reson. Imag. 53(2):540-551 (2021) doi: 10.1002/jmri.27334
3. Sun L, van Amerom JFP, Marini D, Portnoy S, Lee FT, Saini BS, Lim J, Aguet J, Jaeggi E, Kingdom J, Macgowan CK, Miller S, Huang G, Seed M. Characterization of hemodynamic patterns in human fetuses with cyanotic congenital heart disease using MRI  Ultrasound Obstet. Gynecol. 58(6):824-836 (2021) doi: 10.1002/uog.23707
4. Schrauben EM, Darby JRT, Saini B, Holman SL, Lock MC, Perumal SR, Seed M, *Morrison JL, *Macgowan CK. Technique for Comprehensive Fetal Hepatic Blood Flow Assessment in Sheep using 4D flow MRI J. Physiol. 598.17:3555-3567 (2020) doi: 10.1113/JP279631
5. Schrauben EM, Lim J, Goolaub D, Marini D, Seed M, Macgowan CK. Motion-robust 3D radial phase-contrast MRI: implementation in neonatal CHD Magn. Reson. Med.83(2):535–548 (2020) doi: 10.1002/mrm.27945
6. Roy CW, Marini D, Segars WP, Seed M, Macgowan CK. Fetal XCMR: A Numerical Phantom for Fetal Cardiovascular Magnetic Resonance Imaging J. Cardiov. Magn. Reson.21(1):29 (2019) doi:10.1186/s12968-019-0539-2
7. Roy CW, Macgowan CK. Dynamic MRI of a Large Fetal Cardiac Mass Radiology 290(2):288 (2019) doi: 10.1148/radiol.2018182025
8. Schrauben EM, Saini B, Darby JRT, Soo JY, Lock MC, Stirrat E, Stortz G, Sled JG, Morrison JL, Seed M, Macgowan CK. Fetal hemodynamics and cardiac streaming assessed by 4D flow cardiovascular magnetic resonance in fetal sheep J. Cardiov. Magn. Reson. 21(1):8 (2019) doi: 10.1186/s12968-018-0512-5
9. Roy CW, Marini D, Lloyd DFA, Mawad W, Yoo SJ, Seed M, Macgowan CK. Preliminary Experience Using Motion Compensated CINE MRI to Visualize Fetal Congenital Heart Disease: Comparison to Echocardiography Circ. Cardiovasc. Imaging. 11:12 (2018) doi: 10.1161/CIRCIMAGING.118.007745
10. Goolaub DS, Roy C, Schrauben EM, Sussman D, Marini D, Seed M, Macgowan CK. Multidimensional fetal flow imaging with cardiovascular magnetic resonance: a feasibility study J. Cardiov. Magn. Reson. 20(1):77 (2018) doi: 10.1186/s12968-018-0498-z
11. Portnoy S, Milligan N, Seed M, Sled JG, Macgowan CK. Human umbilical cord blood relaxation times and susceptibility at 3 T Magn. Reson. Med. 79(6): 3194-3206 (2018)  doi: 10.1002/mrm.26978
12. Portnoy S, Seed M, Sled JG, Macgowan CK. Non-invasive evaluation of blood oxygen saturation and hematocrit from T1 and T2 relaxation times: in-vitro validation in fetal blood Magn. Reson. Med. 78(6):2352-2359 (2017) doi:10.1002/mrm.26599
13. Roy CW, Seed M, Kingdom JC, Macgowan CK. Motion compensated cine CMR of the fetal heart using radial undersampling and compressed sensing J. Cardiov. Magn. Reson. 19:29 (2017) doi: 10.1186/s12968-017-0346-6
14. Portnoy S, Osmond M, Zhu MY, Seed M, Sled J, Macgowan CK.  Relaxation Properties of Human Umbilical Cord Blood at 1.5 Tesla Magn. Reson. Med. 77(4):1678–1690 (2017)  doi: 10.1002/mrm.26231

Grants

External Funding Sources

• Advanced Fetal MRI Methods to Evaluate Prenatal Organ Development and Predict Postnatal Outcome in Congenital Heart Disease
• Brain Treatment Effects in Childhood Leukaemia Patients Revealed by Motion-Compensated MRI -
• A New Approach to Vascular Reconstruction using Graphical 3D Printing and Flow Modelling to Create Personalised Precision Engineered Surgery
• Does exposure to micro- and nanoplastics impact pregnancy and fetal development?
• Opening and closing doors in the fetal circulation
• Hemodynamics of Pediatric Congenital Heart Disease Using Accelerated and Motion-Compensated MRI
• Accelerated Multi-Dimensional Flow Encoding by MRI

Graduate Students

Valérie Béland
Fatemeh Rastegar
Troy Umolac