The long term goal of this project is to assess the regional diastolic elastic properties of the left ventricular (LV) myocardium in normal and diseased states. The analysis will be performed on the three-dimensional (3D) reconstructed geometry of the LV from rapid acquisition computed tomographic images (cine CT) using the finite element technique.
The specific aims for the three years of requested funding are (i) Validation of the geometric LV reconstruction using; (a) shape analysis of the reconstruction from the cine CT images of in vitro dog heart specimens; (b) computed LV mass, volume and ejection fractions with those obtained from Simpson's rule on images obtained in patients undergoing diagnostic cine CT scans. (ii) Studies on regional elastic modulus of the LV in vivo: (a) the finite element analysis will be extended to include the nonlinear diastolic material properties of the myocardium during diastolic expansion of reconstructed 3D geometry from cine CT images of the LV dogs; (b) Global and regional elastic moduli will be determined in normal subjects and in patients who will undergo cine CT scanning within 72 hours of a first (clinical) myocardial infarction. The location and extent of detected abnormalities in elastic moduli will be correlated with the location of the infarct as determined from ECG and radioisotopic or cineangiographic criteria.
