Hindawi Publishing Corporation Journal of Biomedicine and Biotechnology Volume 2012, Article ID 504037, 10 pages doi:10.1155/2012/504037 Research Article Long-Term Left Ventricular Remodelling in Rat Model of Nonreperfused Myocardial Infarction: Sequential MR Imaging Using a 3T Clinical Scanner Muhammad G. Saleh, 1 Sarah-Kate Sharp, 2 Alkathafi Alhamud, 1 Bruce S. Spottiswoode, 1, 3 Andre J. W. van der Kouwe, 4, 5 Neil H. Davies, 2 Thomas Franz, 2, 6, 7 and Ernesta M. Meintjes 1 1 MRC/UCT Medical Imaging Research Unit, Department of Human Biology, University of Cape Town, Observatory 7925, South Africa 2 Cardiovascular Research Unit, Chris Barnard Division of Cardiothoracic Surgery, University of Cape Town, Observatory 7925, South Africa 3 Division of Radiodiagnosis, Stellenbosch University, Matieland 7602, South Africa 4 Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA 02129, USA 5 Department of Radiology, Harvard Medical School, Boston, MA 02115, USA 6 Centre for Research in Computational and Applied Mechanics, University of Cape Town, Rondebosch 7701, South Africa 7 Centre for High Performance Computing, Rosebank 7700, South Africa Correspondence should be addressed to Muhammad G. Saleh, mgsaleh7@gmail.com Received 6 March 2012; Accepted 11 June 2012 Academic Editor: M. Piacentini Copyright © 2012 Muhammad G. Saleh et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Purpose. To evaluate whether 3T clinical MRI with a small-animal coil and gradient-echo (GE) sequence could be used to charac- terize long-term left ventricular remodelling (LVR) following nonreperfused myocardial infarction (MI) using semi-automatic seg- mentation software (SASS) in a rat model. Materials and Methods. 5 healthy rats were used to validate left ventricular mass (LVM) measured by MRI with postmortem values. 5 sham and 7 infarcted rats were scanned at 2 and 4 weeks after surgery to allow for functional and structural analysis of the heart. Measurements included ejection fraction (EF), end-diastolic volume (EDV), end- systolic volume (ESV), and LVM. Changes in different regions of the heart were quantified using wall thickness analyses. Results. LVM validation in healthy rats demonstrated high correlation between MR and postmortem values. Functional assessment at 4 weeks after MI revealed considerable reduction in EF, increases in ESV, EDV, and LVM, and contractile dysfunction in infarcted and noninfarcted regions. Conclusion. Clinical 3T MRI with a small animal coil and GE sequence generated images in a rat heart with adequate signal-to-noise ratio (SNR) for successful semiautomatic segmentation to accurately and rapidly evaluate long-term LVR after MI. 1. Introduction Assessment of ventricular function and mass is an important guide for predicting survival in patients suffering from dif- ferent cardiovascular diseases, such as ischemic heart disease [1]. In addition, the efficacy of long-term drug therapy of compounds such as angiotensin-converting enzyme (ACE) inhibitor and beta-adrenergic blocking agents are evaluated by assessment of left ventricular (LV) mass and function [2]. Rat models have been widely used to study LV performance and remodelling after induction of myocardial infarction (MI) [3, 4]. In addition, the effects of ACE inhibitors and captopril have been examined in this way [1, 5]. Hence, non- invasive methods to accurately quantify ventricular mass and function are invaluable to clinical and preclinical research. Cardiac magnetic resonance imaging has been consid- ered the optimal tool for noninvasive evaluation of LV func- tion and mass due to its ability to acquire images with high spatial resolution and superb soft tissue contrast without risk of radiation [6–8]. Also, it allows for noninvasive imaging on