Left coronary artery biomechanics: a characterization study using fluid structure interaction simulations

Patient-specific coronary artery biomechanics studies often have limited sample size. The goals of this study were: (1) To develop more patient-specific FSI models to expand current research effort in characterizing hemodynamic and biomechanical conditions within the coronary arteries; (2) to compare some of our model outputs, especially FSI model-generated vFFR values, to those provided by HeartFlow, to evaluate the clinical relevance of our model results. Ten healthy LCA geometries were used to develop patient-specific FSI models using COMSOL Multiphysics. The hemodynamic and biomechanical environment in the arterial wall were assessed, along the proximal, mid, and distal portions of the left anterior descending coronary artery (LAD). The FSI model-calculated vFFR was compared to the matched HeartFlow reports. All FSI models indicated healthy perfusion. There was a good agreement with the HeartFlow calculation in the proximal LAD. The FSI model results indicated that the wall stresses were below the rupture thresholds. However, variations were observed along the arterial length in the von-Mises stress and strains. The FSI models offered improved physiological relevance for LCA simulation by including a large field of view. The biomechanical parameters were minimally related to geometric features, necessitating this procedure. This FSI modeling approach presented a few limitations. More work is needed to address these limitations and improve the physiological relevance of FSI modeling, so it can serve as a non-invasive method to assess the biomechanics of the coronary arteries, to support clinician's decision making.