title: Vorticity is a marker of diastolic ventricular interdependency in pulmonary hypertension.
abstract: Our objective was to determine whether left ventricular (LV) vorticity (ω), the local spinning motion of a fluid element, correlated with markers of ventricular interdependency in pulmonary hypertension (PH). Maladaptive ventricular interdependency is associated with interventricular septal shift, impaired LV performance, and poor outcomes in PH patients, yet the pathophysiologic mechanisms underlying fluid-structure interactions in ventricular interdependency are incompletely understood. Because conformational changes in chamber geometry affect blood flow formations and dynamics, LV ω may be a marker of LV-RV (right ventricular) interactions in PH. Echocardiography was performed for 13 PH patients and 10 controls for assessment of interdependency markers, including eccentricity index (EI), and biventricular diastolic dysfunction, including mitral valve (MV) and tricuspid valve (TV) early and late velocities (E and A, respectively) as well as MV septal and lateral early tissue Doppler velocities (e'). Same-day 4-dimensional cardiac magnetic resonance was performed for LV E (early)-wave ω measurement. LV E-wave ω was significantly decreased in PH patients (P = 0.008) and correlated with diastolic EI (Rho = -0.53, P = 0.009) as well as with markers of LV diastolic dysfunction, including MV E(Rho = 0.53, P = 0.011), E/A (Rho = 0.56, P = 0.007), septal e' (Rho = 0.63, P = 0.001), and lateral e' (Rho = 0.57, P = 0.007). Furthermore, LV E-wave ω was associated with indices of RV diastolic dysfunction, including TV e' (Rho = 0.52, P = 0.012) and TV E/A (Rho = 0.53, P = 0.009). LV E-wave ω is decreased in PH and correlated with multiple echocardiographic markers of ventricular interdependency. LV ω may be a novel marker for fluid-tissue biomechanical interactions in LV-RV interdependency.
authors.affiliation: Department of Cardiology, National Jewish Health, University of Colorado, Denver, Colorado, USA; Department of Bioengineering, University of Colorado, Anschutz Medical Campus, Denver, Colorado, USA.
authors.forename: Michal
authors.initials: M
authors.lastname: Schäfer
authors.affiliation: Department of Mechanical Engineering, University of Colorado, Boulder, Colorado, USA.
authors.forename: James
authors.initials: J
authors.lastname: Browning
authors.affiliation: Department of Radiology, National Jewish Health, University of Colorado, Denver, Colorado, USA.
authors.forename: Joyce D
authors.initials: JD
authors.lastname: Schroeder
authors.affiliation: Department of Bioengineering, University of Colorado, Anschutz Medical Campus, Denver, Colorado, USA.
authors.forename: Robin
authors.initials: R
authors.lastname: Shandas
authors.affiliation: Department of Bioengineering, University of Colorado, Anschutz Medical Campus, Denver, Colorado, USA.
authors.forename: Vitaly O
authors.initials: VO
authors.lastname: Kheyfets
authors.affiliation: Department of Cardiology, National Jewish Health, University of Colorado, Denver, Colorado, USA.
authors.forename: J Kern
authors.initials: JK
authors.lastname: Buckner
authors.affiliation: Department of Bioengineering, University of Colorado, Anschutz Medical Campus, Denver, Colorado, USA.
authors.forename: Kendall S
authors.initials: KS
authors.lastname: Hunter
authors.affiliation: Department of Mechanical Engineering, University of Colorado, Boulder, Colorado, USA.
authors.forename: Jean R
authors.initials: JR
authors.lastname: Hertzberg
authors.affiliation: Department of Cardiology, National Jewish Health, University of Colorado, Denver, Colorado, USA.
authors.forename: Brett E
authors.initials: BE
authors.lastname: Fenster
keywords: cardiac magnetic resonance imaging; pulmonary hypertension; vorticity