Turbulent kinetic energy in normal and myopathic left ventricles.
OBJECTIVE
To assess turbulent kinetic energy (TKE) within the left ventricle (LV) of healthy subjects using novel 4D flow magnetic resonance imaging (MRI) methods and to compare TKE values to those from a limited group of patients with a spectrum of dilated cardiomyopathy (DCM).


METHODS
4D flow and morphological MRI data were acquired in 11 healthy subjects and 9 patients with different degrees of diastolic dysfunction. TKELV was calculated within the LV at each diastolic timeframe. At peak early (E) and late (A) diastolic filling, the TKELV was compared to transmitral peak velocity, LV diameter, and mitral annular diameter.


RESULTS
In the majority of subjects, TKELV peaks were observed at E and A. Peak TKELV at E was not different between the groups (P = 0.33), and correlated with mitral annular dimensions (r(2) = 0.32, P = 0.01). Peak TKELV at A was higher in DCM patients compared to healthy subjects (3.0 ± 1.8 vs. 1.5 ± 0.8 mJ, P = 0.02), and correlated with LV diameter and transmitral velocity (r(2) = 0.36, P = 0.01 and r(2) = 0.47, P < 0.01, respectively).


CONCLUSIONS
In LVs of healthy subjects, TKE values are low. Values are highest during early diastole, and diminish with increasing LV size. In a heterogeneous group of DCM patients, late diastolic TKE values are higher than in healthy subjects.
Division of Cardiovascular Medicine, Department of Medical and Health Sciences, Linköping University, Linköping, Sweden; Center for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden; Department of Clinical Physiology, UHL, County Council of Östergötland, Linköping, Sweden.
Jakub
J
Zajac
Jonatan
J
Eriksson
Petter
P
Dyverfeldt
Ann F
AF
Bolger
Tino
T
Ebbers
Carl-Johan
CJ
Carlhäll
D000328:Adult; D001783:Blood Flow Velocity; D002311:Cardiomyopathy, Dilated / Q000150:complications / Q000503:physiopathology*; D003326:Coronary Circulation; D005260:Female; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D017711:Nonlinear Dynamics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000209:etiology / Q000503:physiopathology*
blood flow; cardiac function; diastolic dysfunction; heart failure; magnetic resonance imaging; turbulent flow