The Quantitative Evaluation On Left Ventricular Energy Loss During Diastole In Patients With Left Ventricular Non-compaction Using Ultrasonic Vector Flow Mapping

Objective: To assess left intraventricular blood flow patterns in patients with left ventricular non-compaction(LVNC), and diastolic left ventricular energy loss(EL) quantitatively, and to explore the application value of left ventricle energy loss for diastolic dysfunction using ultrasonic vector flow mapping(VFM).Method: Totally 62 patients with LVNC were employed as observation group and sub-divided into clinical group(LVNC1) of 37 cases and pre-clinical group(LVNC2) of 25 cases, 61 cases of healthy were selected as control group. Hitachi Aloka Prosound F75 color Doppler ultrasound diagnostic system is used to acquire standard dynamic apical 3 chamber and 4 chamber view color Doppler flow images and left ventricular long axis, short axis two-dimensional view images in 3 completed cardiac cycles for the measurement of general parameters of left ventricular function. A dedicated off-line workstation was used to acquire the EL、vortex area and circulation derived from the dynamic color Doppler flow images. The diastole of left ventricle was divided into the isovolumic relaxation phase(P1), early diastolic phase(P2), rapid filling phase(P3), slow filling phase(P4), atria contract period(P5), late diastolic phase(P6) and total diastolic phase(P0)based on time-flow curve(T-F curve). The differences of conventional functional parameters, noncompaction(NC) or compaction(C)myocardial thickness EL value were comparedand the correlation ships between EL and conventional diastolic functional parameters, vortex area and circulation above the groups were analyzed.Result:1. The qualitative observations: Compared between LVNC group and healthy control group, the blood flow velocity and direction of left ventricular changed in each diastolic phases, speed vector was unstable and there were more turbulent flow and vortex formation, the concentrated distribution of EL was getting larger and the color hue becoming brighter obviously near the turbulences and vortice during diastole in LVNC. Compared between LVNC1 group and healthy control group, speed vector was unstable, the number of vortex increased significantly, the concentrated distribution of EL was getting larger and more dispersal during diastole in LVNC1 group. Compared between LVNC2 group and healthy control group, the number of vortex was increased, and the distribution of EL is more dispersal during diastole in LVNC2 group. Compared between LVNC1 group and LVNC2 group, speed vector was unstable, the number of vortex increased, the concentrated distribution of EL was getting larger. Vortical number: Compared between LVNC group and healthy control group, the number of vortex was increased with statistical significance in P1, P3, P4 phases(p<0.05). Compared between LVNC1 group and healthy control group, the number of vortex was increased with statistical significance in P1, P2, P3, P4, P5 phases(p<0.05). Compared between LVNC2 group and healthy control group, the number of vortex was increased in P3, P4 phases,but the difference was not statistically significant(p>0.05). Compared between LVNC1 group and LVNC2 group, the number of vortex was increased with statistical significance in P3, P4, P5 phases(p<0.05).2.The quantitative analysis:(1) left ventricular conventional functional parameters: Compared between LVNC group and healthy control group, the LVEF, A, a, e/a were lower with statistical significance(p<0.05).(2) NC、C、NC/C value: Compared between LVNC1 group and LVNC2 group,the NC、NC/C value of LVNC1 group were higher and the C value were lower with statistical significance(p<0.05).(3) EL value: Compared between LVNC group and healthy control group, the EL of all periods of LVNC group was higher with statistical significance in P2, P3, P0 phases(p<0.05). Compared between LVNC 1group and healthy control group, the EL of all periods of LVNC 1group was higher with statistical significance in P1,P2, P3, P4, P0 phases(p<0.05). Compared between LVNC2 group and healthy control group, the EL of all periods of LVNC2 group was higher without statistically significant(p>0.05). Compared between LVNC1 group and LVNC2 group, the EL of all periods of LVNC1 group was higher with statistical significance in P3, P5, P0 phases(p<0.05).3、Correlation analysis: In healthy control group, there were positive correlations between P3-EL and E, E/A, e, e/a(p<0.05), and negative correlation between P3-EL and A(p<0.05), and positive correlations between P5-EL and A, a, E/e(p<0.05) and negative correlations between P5-EL and E/A, e, e/a(p<0.05). In LVNC group, there were positive correlations existed between P3-EL and E, E/A, e, e/a(p<0.05) and positive correlations between P5-EL and A, a, E/e(p<0.05) and negative correlations between P5-EL and E/A, e, e/a(p<0.05). In healthy control group, there was a positive correlation between P0-EL value and vortex circulation(p<0.05). In LVNC group, there was a positive correlation between P0-EL value and vortex circulation(p<0.05) and negative correlation between P0-EL value and vortex area.Conclusion: The abnormal vorticity could be induced by LVNC, which related to the left ventricular high EL in most phases of diastole, and there is a difference of EL in the severity LVNC. The EL value and vortex circulation is positive correlation. The left ventricular EL might be used as a new quantitative index for evaluating the left ventricular dysfunction of LVNC.