Simbios Talk by Julius Guccione, University of California San Francisco, December 13, 2005

Title: Effect of heart chamber size and patch stiffness in surgical ventricular restoration: a physics-based simulation

Surgical ventricular restoration (SVR) has been proposed for dilated hearts with oronary artery disease. We tested the hypothesis that SVR increases cardiac output, reduces load or stress on the cardiac muscle fibers and achieves optimal results without a patch. A mathematical (finite element) model of the left ventricle (LV) with an akinetic but contractile anteroapical LV wall segment was used. Separate versions of the model with normal and dilated LV sizes were developed and used to simulate the SVR operation with and without a patch of varying stiffness. The SVR operation was more beneficial in dilated ventricles, and the reduction in cardiac output after SVR without patch was minimal. The effect of patch stiffness was mixed as stiffer material causes a greater reduction in stress yet has the greatest negative effect on cardiac output. Thus, these simulations support the use of SVR in dilated hearts without a patch.