A quantitative high resolution voxel-wise assessment of myocardial blood flow from contrast-enhanced first-pass magnetic resonance perfusion imaging: microsphere validation in a magnetic resonance compatible free beating explanted pig heart model.

Abstract

AIMS:

To assess the feasibility of high-resolution quantitative cardiovascular magnetic resonance (CMR) voxel-wise perfusion imaging using clinical 1.5 and 3 T sequences and to validate it using fluorescently labelled microspheres in combination with a state of the art imaging cryomicrotome in a novel, isolated blood-perfused MR-compatible free beating pig heart model without respiratory motion.

METHODS AND RESULTS:

MR perfusion imaging was performed in pig hearts at 1.5 (n = 4) and 3 T (n = 4). Images were acquired at physiological flow ('rest'), reduced flow ('ischaemia'), and during adenosine-induced hyperaemia ('stress') in control and coronary occlusion conditions. Fluorescently labelled microspheres and known coronary myocardial blood flow represented the reference standards for quantitative perfusion validation. For the comparison with microspheres, the LV was divided into 48 segments based on a subdivision of the 16 AHA segments into subendocardial, midmyocardial, and subepicardial subsegments. Perfusion quantification of the time-signal intensity curves was performed using a Fermi function deconvolution. High-resolution quantitative voxel-wise perfusion assessment was able to distinguish between occluded and remote myocardium (P < 0.001) and between rest, ischaemia, and stress perfusion conditions at 1.5 T (P < 0.001) and at 3 T (P < 0.001). CMR-MBF estimates correlated well with the microspheres at the AHA segmental level at 1.5 T (r = 0.94, P < 0.001) and at 3 T (r = 0.96, P < 0.001) and at the subendocardial, midmyocardial, and subepicardial level at 1.5 T (r = 0.93, r = 0.9, r = 0.88, P < 0.001, respectively) and at 3 T (r = 0.91, r = 0.95, r = 0.84, P < 0.001, respectively).

CONCLUSION:

CMR-derived voxel-wise quantitative blood flow assessment is feasible and very accurate compared with microspheres. This technique is suitable for both clinically used field strengths and may provide the tools to assess extent and severity of myocardial ischaemia.

• Authors: Andreas Schuster, Matthew Sinclair, Niloufar Zarinabad, Masaki Ishida, Jeroen P H M van den Wijngaard, Matthias Paul, Pepijn van Horssen, Shazia T Hussain, Divaka Perera, Tobias Schaeffter, Jos A E Spaan, Maria Siebes, Eike Nagel, Amedeo Chiribiri
• Journal: European heart journal. Cardiovascular Imaging (Eur Heart J Cardiovasc Imaging) Vol. 16 Issue 10 Pg. 1082-92 (Oct 2015) ISSN: 2047-2412 [Electronic] England
• PMID: 25812572 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Validation Study)
• Copyright: Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: [email protected].

Chemical References

• Contrast Media
• Organometallic Compounds
• gadobutrol

Topics

• Algorithms
• Animals
• Blood Flow Velocity
• Contrast Media
• Coronary Circulation (physiology)
• Feasibility Studies
• Hyperemia (physiopathology)
• Image Enhancement (methods)
• Image Processing, Computer-Assisted (methods)
• Magnetic Resonance Imaging (methods)
• Microspheres
• Models, Animal
• Organometallic Compounds
• Signal-To-Noise Ratio
• Swine