An isolated perfused pig heart model for the development, validation and translation of novel cardiovascular magnetic resonance techniques.
BACKGROUND
Novel cardiovascular magnetic resonance (CMR) techniques and imaging biomarkers are often validated in small animal models or empirically in patients. Direct translation of small animal CMR protocols to humans is rarely possible, while validation in humans is often difficult, slow and occasionally not possible due to ethical considerations. The aim of this study is to overcome these limitations by introducing an MR-compatible, free beating, blood-perfused, isolated pig heart model for the development of novel CMR methodology.


METHODS
6 hearts were perfused outside of the MR environment to establish preparation stability. Coronary perfusion pressure (CPP), coronary blood flow (CBF), left ventricular pressure (LVP), arterial blood gas and electrolyte composition were monitored over 4 hours. Further hearts were perfused within 3T (n = 3) and 1.5T (n = 3) clinical MR scanners, and characterised using functional (CINE), perfusion and late gadolinium enhancement (LGE) imaging. Perfusion imaging was performed globally and selectively for the right (RCA) and left coronary artery (LCA). In one heart the RCA perfusion territory was determined and compared to infarct size after coronary occlusion.


RESULTS
All physiological parameters measured remained stable and within normal ranges. The model proved amenable to CMR at both field strengths using typical clinical acquisitions. There was good agreement between the RCA perfusion territory measured by selective first pass perfusion and LGE after coronary occlusion (37% versus 36% of the LV respectively).


CONCLUSIONS
This flexible model allows imaging of cardiac function in a controllable, beating, human-sized heart using clinical MR systems. It should aid further development, validation and clinical translation of novel CMR methodologies, and imaging sequences.
Schuster
Andreas
A
King's College London BHF Centre of Excellence, NIHR Biomedical Research Centre, Guy's and St, Thomas' NHS Foundation Trust, Division of Imaging Sciences, The Rayne Institute, London, UK.
Grünwald
Inga
I
Chiribiri
Amedeo
A
Southworth
Richard
R
Ishida
Masaki
M
Hay
Gunnar
G
Neumann
Nicole
N
Morton
Geraint
G
Perera
Divaka
D
Schaeffter
Tobias
T
Nagel
Eike
E
D000818:Animals; D003287:Contrast Media; D003326:Coronary Circulation; D054059:Coronary Occlusion / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D004195:Disease Models, Animal; D005240:Feasibility Studies; D019028:Magnetic Resonance Imaging, Cine; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D009206:Myocardium / Q000473:pathology*; D009942:Organometallic Compounds; D010477:Perfusion; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D013552:Swine; D057170:Translational Research, Biomedical; D016276:Ventricular Function; D017725:Ventricular Pressure
D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol