Related Experiment Video
Updated: Oct 22, 2025
Assessment of Cardiac Morphological and Functional Changes in Mouse Model of Transverse Aortic Constriction by Echocardiographic Imaging
Published on: June 21, 2016
Effect of Loading Changes on the Intraventricular Pressure Measured by Color M-Mode Echocardiography in Rats
Akira Yairo1, Ahmed S Mandour1,2, Katsuhiro Matsuura1
1Laboratory of Veterinary Surgery, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, Tokyo 183-0054, Japan.
Color M-mode echocardiography (CMME) provides novel intraventricular pressure difference (IVPD) and gradient (IVPG) indices for assessing rat cardiac diastolic function. These CMME-derived measures effectively reflect changes in cardiac loading conditions, aiding heart failure diagnosis.
Area of Science:
- Cardiovascular Physiology
- Echocardiography
- Heart Failure Research
Background:
- Evaluating diastolic function in rats is challenging due to rapid heart rates and conventional echocardiography limitations.
- Intraventricular pressure difference (IVPD) and gradient (IVPG) derived from color M-mode echocardiography (CMME) show promise for early heart failure diagnosis.
- Previous studies have not investigated IVPD and IVPG responses to altered loading conditions in rats.
Purpose of the Study:
- To evaluate changes in CMME-derived IVPD and IVPG in rats under varying hemodynamic loading conditions.
- To assess the utility of CMME-derived IVPD and IVPG as indicators of altered cardiac relaxation and volume status.
Main Methods:
- Twenty rats underwent jugular vein catheterization and conventional echocardiography, CMME, and 2D speckle tracking.
- Measurements were taken at baseline, after milrinone (MIL) infusion (vasodilator/inotropic agent), and after hydroxyethyl starch (HES) infusion (volume expansion).
- Left ventricular IVPD and IVPG were calculated from CMME images and analyzed in different segments.
Main Results:
- Milrinone administration significantly increased ejection fraction and mid-to-apical/mid/apical IVPG and IVPD, indicating improved relaxation.
- Hydroxyethyl starch infusion significantly increased end-diastolic volume, E-wave velocity, total IVPD, and basal IVPD, reflecting volume overload.
- CMME-derived IVPD and IVPG successfully differentiated responses to inotropic/vasodilator and volume loading conditions.
Conclusions:
- CMME-derived IVPD and IVPG are valuable tools for assessing diverse loading conditions in rat models.
- This approach enables continuous data acquisition in chronic cardiac disease models without necessitating drug interventions.
- The study establishes CMME-derived IVPD and IVPG as sensitive indices for evaluating diastolic function and hemodynamic changes in rats.
