Assessment of myocardial viscoelasticity with Brillouin spectroscopy in myocardial infarction and aortic stenosis models

• Published in: Scientific reports 2021-11, Vol.11 (1), p.21369-21369, Article 21369
• Main Authors: Villalba-Orero, María, Jiménez-Riobóo, Rafael J., Gontán, Nuria, Sanderson, Daniel, López-Olañeta, Marina, García-Pavía, Pablo, Desco, Manuel, Lara-Pezzi, Enrique, Gómez-Gaviro, Maria Victoria
• Format: Article
• Language: English
• Subjects: 631/1647; 631/57; 692/4019; Animals; Aortic stenosis; Aortic Valve Stenosis - diagnosis; Aortic Valve Stenosis - pathology; Biological samples; Cardiovascular diseases; Coronary artery disease; Disease Models, Animal; Echocardiography; Elasticity; Elasticity Imaging Techniques; Heart; Heart diseases; Humanities and Social Sciences; Male; Mechanical properties; Mice; Mice, Inbred C57BL; multidisciplinary; Myocardial infarction; Myocardial Infarction - diagnosis; Myocardial Infarction - pathology; Myocardium; Myocardium - pathology; Science; Science (multidisciplinary); Spectroscopy; Spectrum Analysis; Ventricle; Viscoelasticity
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-021-00661-4

Heart diseases are associated with changes in the biomechanical properties of the myocardial wall. However, there is no modality available to assess myocardial stiffness directly. Brillouin microspectroscopy (mBS) is a consolidated mechanical characterization technique, applied to the study of the viscoelastic and elastic behavior of biological samples and may be a valuable tool for assessing the viscoelastic properties of the cardiac tissue. In this work, viscosity and elasticity were assessed using mBS in heart samples obtained from healthy and unhealthy mice (n = 6 per group). Speckle-tracking echocardiography (STE) was performed to evaluate heart deformation. We found that mBS was able to detect changes in stiffness in the ventricles in healthy myocardium. The right ventricle showed reduced stiffness, in agreement with its increased compliance. mBS measurements correlated strongly with STE data, highlighting the association between displacement and stiffness in myocardial regions. This correlation was lost in pathological conditions studied. The scar region in the infarcted heart presented changes in stiffness when compared to the rest of the heart, and the hypertrophied left ventricle showed increased stiffness following aortic stenosis, compared to the right ventricle. We demonstrate that mBS can be applied to determine myocardial stiffness, that measurements correlate with functional parameters and that they change with disease.