Modeling the macro-structure of the heart: healthy and diseased.

In a common heart pathology, dilated cardiomyopathy, the ventricular chamber undergoes a complex remodeling that changes the shape of the ventricle and the architecture of the fibers in the myocardium. In order to effectively surgically reconstruct the heart it is necessary to understand the relative impact of these changes on heart function. Here we present a series of simulations that model different pathological changes separately. We use the sensitive relationship between twist of the ventricle and its ejection fraction to judge the functional impact of the different damage types. We show that the anomalies found in the relation between torsion and ejection fraction for dilated cardiomyopathy are predominantly caused by the damage to the architecture of the myofibrils of the heart, rather than gross geometry.