1Department of Medicine and Biological Science, Gunma University Graduate School of Medicine, 2Department of Hemodynamic Analysis, Kitasato University School of Medicine, 3Department of Cardiovascular Medicine, The University of Tokyo Hospital, 4Department of Clinical Laboratory, The Cancer Institute Hospital of JFCR, 5Menzies Research Institute Tasmania, 6Department of Computational Diagnostic Radiology and Preventive Medicine, The University of Tokyo Hospital, 7Department of Cardiovascular Surgery, Kitasato University School of Medicine, 8Department of Cardiovascular Medicine, Nihon University of Medicine, Itabashi Hospital
vortex, VFM (vector flow mapping), color Doppler, speckle tracking, impaired cardiac function
Purpose: Vortex formation in the left ventricle(LV) can be visualized by novel vector flow mapping (VFM) based on color Doppler and speckle tracking data. The aim of this study was to evaluate the impact of a vortex during the ejection period using VFM. Subjects and methods: Color Doppler images were obtained to produce VFM images in 80 subjects (20 normal, 29 with dilated cardiomyopathy, and 31 with old myocardial infarction). The duration of the LV vortex was measured and expressed as the ratio to the ejection time (VTRe). Results: The VTRe showed significant correlations with EDV (ρ= 0.672, p < 0.001), ESV (ρ= 0.772, p < 0.001), EF (ρ=-0.783, p < 0.001), left atrium diameter (LAd) (ρ= 0.302, p = 0.007), stroke volume (ρ=-0.600, p < 0.001), e’ (ρ=-0.389, p < 0.001), a’ (ρ=-0.314, p = 0.005), s’ (ρ=-0.512, p < 0.001), and E/e’ (ρ= 0.330, p = 0.003). The diastolic parameters (e’, a’, E/e’, LAd) were not correlated when they were adjusted by EF. Conclusions: In the normal LV, a vortex existed for only a limited time during the early ejection period. In contrast, the lower the EF was, the longer the vortex remained during systole. Evaluation of vortices by VFM may noninvasively provide novel insights into the pathophysiology of impaired cardiac function.