Background Right ventricular (RV) diastolic function has been associated with outcomes for patients with pulmonary hypertension; however, the relationship between biomechanics and hemodynamics in the right ventricle has not been studied. Methods and Results Rat models of RV pressure overload were obtained via pulmonary artery banding (PAB; control, n=7; PAB, n=5). At 3 weeks after banding, RV hemodynamics were measured using a conductance catheter. Biaxial mechanical properties of the RV free wall myocardium were obtained to extrapolate longitudinal and circumferential elastic modulus in low and high strain regions (E-1 and E-2, respectively). Hemodynamic analysis revealed significantly increased end-diastolic elastance (E-ed) in PAB (control: 55.1 mm Hg/mL [interquartile range: 44.785.4 mm Hg/mL]; PAB: 146.6 mm Hg/mL [interquartile range: 105.8155.0 mm Hg/mL]; P=0.010). Longitudinal E1 was increased in PAB (control: 7.2 kPa [interquartile range: 6.718.1 kPa]; PAB: 34.2 kPa [interquartile range: 18.144.6 kPa]; P=0.018), whereas there were no significant changes in longitudinal E-2 or circumferential E-1 and E-2. Last, wall stress was calculated from hemodynamic data by modeling the right ventricle as a sphere: (stress = Pressure x radius/2 x thickness Conclusions RV pressure overload in PAB rats resulted in an increase in diastolic myocardial stiffness reflected both hemodynamically, by an increase in E-ed, and biomechanically, by an increase in longitudinal E-1. Modest increases in tissue biomechanical stiffness are associated with large increases in E-ed. Hemodynamic measurements of RV diastolic function can be used to predict biomechanical changes in the myocardium.
| Identifer | oai:union.ndltd.org:arizona.edu/oai:arizona.openrepository.com:10150/626001 |
| Date | 12 September 2017 |
| Creators | Jang, Sae, Vanderpool, Rebecca R., Avazmohammadi, Reza, Lapshin, Eugene, Bachman, Timothy N., Sacks, Michael, Simon, Marc A. |
| Contributors | Univ Arizona, Dept Med |
| Publisher | WILEY |
| Source Sets | University of Arizona |
| Language | English |
| Detected Language | English |
| Type | Article |
| Rights | © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley. This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial‐NoDerivs License. |
| Relation | http://jaha.ahajournals.org/lookup/doi/10.1161/JAHA.117.006084 |
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