On estimating intraventricular hemodynamic forces from endocardial dynamics: A comparative study with 4D flow MRI

Research output: Contribution to journalArticle

Abstract

Intraventricular pressure gradients or hemodynamic forces, which are their global measure integrated over the left ventricular volume, have a fundamental importance in ventricular function. They may help revealing a sub-optimal cardiac function that is not evident in terms of tissue motion, which is naturally heterogeneous and variable, and can influence cardiac adaptation. However, hemodynamic forces are not utilized in clinical cardiology due to the unavailability of simple non-invasive measurement tools. Hemodynamic forces depend on the intraventricular flow; nevertheless, most of them are imputable to the dynamics of the endocardial flow boundary and to the exchange of momentum across the mitral and aortic orifices. In this study, we introduce a simplified model based on first principles of fluid dynamics that allows estimating hemodynamic forces without knowing the velocity field inside the LV. The model is validated with 3D phase-contrast MRI (known as 4D flow MRI) in 15 subjects, (5 healthy and 10 patients) using the endocardial surface reconstructed from the three standard long-axis projections. Results demonstrate that the model provides consistent estimates for the base-apex component (mean correlation coefficient r = 0.77 for instantaneous values and r = 0.88 for root mean square) and good estimates of the inferolateral-anteroseptal component (r = 0.50 and 0.84, respectively). The present method represents a potential integration to the existing ones quantifying endocardial deformation in MRI and echocardiography to add a physics-based estimation of the corresponding hemodynamic forces. These could help the clinician to early detect sub-clinical diseases and differentiate between different cardiac dysfunctional states.

Details

Authors
Organisations
External organisations
  • University of Trieste
  • Skåne University Hospital
  • University of Florence
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Medical Laboratory and Measurements Technologies

Keywords

  • 4D flow MRI, Cardiac fluid dynamics, Hemodynamic forces, Intraventricular pressure gradient
Original languageEnglish
Pages (from-to)203-210
Number of pages8
JournalJournal of Biomechanics
Volume60
Publication statusPublished - 2017 Jul 26
Publication categoryResearch
Peer-reviewedYes