title: E-wave generated intraventricular diastolic vortex to L-wave relation: model-based prediction with in vivo validation.
abstract: The Doppler echocardiographic E-wave is generated when the left ventricle's suction pump attribute initiates transmitral flow. In some subjects E-waves are accompanied by L-waves, the occurrence of which has been correlated with diastolic dysfunction. The mechanisms for L-wave generation have not been fully elucidated. We propose that the recirculating diastolic intraventricular vortex ring generates L-waves and based on this mechanism, we predict the presence of L-waves in the right ventricle (RV). We imaged intraventricular flow using Doppler echocardiography and phase-contrast magnetic resonance imaging (PC-MRI) in 10 healthy volunteers. L-waves were recorded in all subjects, with highest velocities measured typically 2 cm below the annulus. Fifty-five percent of cardiac cycles (189 of 345) had L-waves. Color M-mode images eliminated mid-diastolic transmitral flow as the cause of the observed L-waves. Three-dimensional intraventricular flow patterns were imaged via PC-MRI and independently validated our hypothesis. Additionally as predicted, L-waves were observed in the RV, by both echocardiography and PC-MRI. The re-entry of the E-wave-generated vortex ring flow through a suitably located echo sample volume can be imaged as the L-wave. These waves are a general feature and a direct consequence of LV and RV diastolic fluid mechanics.
authors.affiliation: Cardiovascular Biophysics Laboratory, Cardiovascular Division, Washington University, School of Medicine, St. Louis, Missouri; Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri; and.
authors.forename: Erina
authors.initials: E
authors.lastname: Ghosh
authors.affiliation: Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri; and Philips Healthcare, Cleveland, Ohio.
authors.forename: Shelton D
authors.initials: SD
authors.lastname: Caruthers
authors.affiliation: Cardiovascular Biophysics Laboratory, Cardiovascular Division, Washington University, School of Medicine, St. Louis, Missouri; Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri; and sjk@wuphys.wustl.edu.
authors.forename: Sándor J
authors.initials: SJ
authors.lastname: Kovács
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology; D003971:Diastole / Q000502:physiology*; D015150:Echocardiography, Doppler / Q000379:methods; D005260:Female; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D008297:Male; D016277:Ventricular Function, Left / Q000502:physiology*
keywords: cardiac magnetic resonance imaging; diastolic function; echocardiography; intraventricular vortex; ventricular suction