Abstract
(1) Background: The accuracy of the left ventricular volume (LVV) and contractility measurements with cardiac magnetic resonance imaging (CMRI) is decreased if the papillary muscles are abnormally enlarged, such as in hypertrophic cardiomyopathy in human patients or in pig models of human diseases. The purpose of this work was to establish the best method of LVV quantification with CMRI in pigs. (2) Methods: The LVV in 29 Yucatan minipig hearts was measured using two different techniques: the “standard method”, which uses smooth contouring along the endocardial surface and adds the papillary volume to the ventricular cavity volume, and the “detailed method”, which traces the papillary muscles and trabeculations and adds them to the ventricular mass. (3) Results: Papillary muscles add 21% to the LV mass in normal and infarcted hearts of Yucatan minipigs. The inclusion or exclusion of these from the CMRI analysis significantly affected the study results. In the normal pig hearts, the biggest differences were found in measurements of the LVV, ejection fraction (EF), LV mass and indices derived from the LV mass (p < 0.001). The EF measurement in the normal pig heart was 11% higher with the detailed method, and 19% higher in the infarcted pig hearts (p < 0.0001). The detailed method of endocardium tracing with CMRI closely represented the LV mass measured ex vivo. (4) Conclusions: The detailed method, which accounts for the large volume of the papillary muscles in the pig heart, provides better accuracy and interobserver consistency in the assessment of LV mass and ejection fraction, and might therefore be preferable for these analyses.
Highlights
Cardiac magnetic resonance imaging (CMRI), with its high spatial and contrast resolution, especially in soft tissues is considered the gold standard for the non-invasive assessment of the heart structure and contractility
Except for the stroke volume, a very high statistically significant difference was shown for all measured parameters, including LV mass, the left ventricle volume (LVV), the ejection fraction as well as all indices derived from LV mass (p < 0.001, Table 1)
The ejection fraction measurement in the pig heart was 11% higher in the detailed method (p = 2.28 × 10−9)
Summary
Cardiac magnetic resonance imaging (CMRI), with its high spatial and contrast resolution, especially in soft tissues is considered the gold standard for the non-invasive assessment of the heart structure and contractility. CMRI has a high accuracy in the evaluation of the left ventricle volume (LVV) and mass (LV mass) in humans as well as in various experimental animal models [1,2,3,4,5]. Assessment of the LVV is typically done using multiple 2-dimensional short axis slices spanning the heart acquired at the cine mode. Due to the superior image resolution and high contrast between the blood pool and myocardial tissue, the papillary muscles and even the trabeculae of the left ventricle are identified in cine MRI. The normal papillary muscle mass in humans has been reported to be
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
