Assessment of factors affecting left ventricular end-diastolic vortex by vector flow mapping

  AIM  To assess the factors affecting the left ventricular (LV) end-diastolic vortex and the relationships between the vortex and mitral inflow patterns by vector flow mapping (VFM).

  METHODS  Forty-eight healthy volunteers, 51 patients with coronary artery disease and 51 patients with dilated cardiomyopathy were divided into 4 groups according to their transmitral flow patterns: 29 with normal filling, 85 with E/A ratio <1, 22 with pseudonormal filling, and 14 with restrictive filling. Color Doppler data in LV were recorded in apical long axis view and area and flux of the end-diastolic vortex were measured by VFM.

  RESULTS  In the cohort of all the subjects, the area of the end-diastolic vortex was significantly correlated with heart rate, transmitral A velocity, mitral annulus a’ velocity and LV size. Transmitral A velocity, heart rate and LV end-diastolic long diameter were the independent predictors of vortex area (adjusted R²=0.181, P<0.01). Flux of the vortex was significantly correlated with age, heart rate, transmitral A velocity, LV size and parameters of LV function. Transmitral A velocity, heart rate, and LV end-systolic short and end-diastolic long diameters were the independent predictors of vortex flux (adjusted R²=0.575, P<0.01). There were significant differences between the 4 groups in area and flux of the vortex. The group with E/A ratio <1 had a larger vortex area than the group with restrictive filling, and the groups with normal filling and E/A ratio <1 had a larger vortex flux than the groups with pseudonormal and restrictive filling (all P<0.05).

  CONCLUSION  The formation of the end-diastolic vortex is associated with transmitral A velocity, heart rate, and LV size. The difference in the vortex of different LV filling patterns suggests that the end-diastolic vortex can be used to distinguish between a normal and pseudonormal LV filling pattern.