Non-invasive in silico determination of ventricular wall pre-straining and characteristic cavity pressures

TL;DR

This paper presents a novel non-invasive computational method to determine ventricular wall pre-straining and cavity pressures in patient-specific heart models, enhancing the accuracy of cardiac mechanics simulations.

Contribution

It introduces an iterative inverse parameter optimization framework that estimates key cardiac parameters without invasive measurements.

Findings

Successfully estimates ventricular pre-straining and cavity pressures

Enhances accuracy of patient-specific heart modeling

Provides a non-invasive approach for cardiac parameter determination

Abstract

The clinical application of patient-specific modelling of the heart can provide valuable insights in supplementing and advancing methods of diagnosis as well as helping to devise the best possible therapeutic approach for each individual pathological heart condition. The potential of computational cardiac mechanics, however, has not yet been fully leveraged due to the heart's complex physiology and limitations in the non-invasive in vivo characterisation of heart properties necessary required for accurate patient-specific modelling such as the heart anatomy in an unloaded state, ventricular pressure, the elastic constitutive parameters and the myocardial muscle fibre orientation distribution. From a solid mechanics point of view without prior knowledge of the unloaded heart configuration and the cavity pressure-volume evolution, in particular, the constitutive parameters cannot be accurately estimated to describe the highly nonlinear elastic material behaviour of myocardial tissue. Here, knowledge of the volume-normalized end-diastolic pressure relation for larger mammals is exploited in combination with a novel iterative inverse parameter optimisation framework to determine end-systolic and end diastolic pressures, ventricular wall pre-straining and pre-stressing due the residual end-systolic cavity pressure as well as myocardial tissue stiffness parameters for biventricular heart models.