Abstract:
Diastolic vortex ring (VR) plays a key role in the blood-pumping function exerted by the left ventricle (LV), with altered VR structures being associated with LV dysfunction. Herein, we sought to characterize the VR diastolic alterations in ischemic cardiomyopathy (ICM) patients with systo-diastolic LV dysfunction, as compared to healthy controls, in order to provide a more comprehensive understanding of LV diastolic function. 4D Flow MRI data were acquired in ICM patients (n = 15) and healthy controls (n = 15). The λ2 method was used to extract VRs during early and late diastolic filling. Geometrical VR features, e.g., circularity index (CI), orientation (α), and inclination with respect to the LV outflow tract (ß), were extracted. Kinetic energy (KE), rate of viscous energy loss ( EL ˙ ), vorticity (W), and volume (V) were computed for each VR; the ratios with the respective quantities computed for the entire LV were derived. At peak E-wave, the VR was less circular (p = 0.032), formed a smaller α with the LV long-axis (p = 0.003) and a greater ß (p = 0.002) in ICM patients as compared to controls. At peak A-wave, CI was significantly increased (p = 0.034), while α was significantly smaller (p = 0.016) and β was significantly increased (p = 0.036) in ICM as compared to controls. At both peak E-wave and peak A-wave, EL ˙ VR / EL ˙ LV , WVR/WLV, and VVR/VLV significantly decreased in ICM patients vs. healthy controls. KEVR/VVR showed a significant decrease in ICM patients with respect to controls at peak E-wave, while VVR remained comparable between normal and pathologic conditions. In the analyzed ICM patients, the diastolic VRs showed alterations in terms of geometry and energetics. These derangements might be attributed to both structural and functional alterations affecting the infarcted wall region and the remote myocardium.
摘要:
舒张涡流环(VR)在左心室(LV)的抽血功能中起关键作用,VR结构改变与LV功能障碍相关。在这里,我们试图描述缺血性心肌病(ICM)患者的VR舒张改变与systo-舒张功能不全,与健康对照相比,以期对左室舒张功能有更全面的认识。在ICM患者(n=15)和健康对照(n=15)中获得4DFlowMRI数据。λ2方法用于在舒张早期和晚期充盈期间提取VRs。几何VR功能,例如,圆形指数(CI),取向(α),和相对于左心室流出道的倾斜度(β),被提取。动能(KE),粘性能损失率(EL•),涡度(W),计算每个VR的体积(V);得出整个LV的相应数量的比率。在峰值E波,VR的圆形较小(p=0.032),与对照组相比,ICM患者的LV长轴形成较小的α(p=0.003)和较大的β(p=0.002)。在峰值A波,CI显著增加(p=0.034),与对照组相比,ICM中的α显着减小(p=0.016),β显着增加(p=0.036)。在峰值E波和峰值A波时,EL•VR/EL•LV,WVR/WLV,与ICM患者相比,VVR/VLV显着降低健康的控制。KEVR/VVR显示ICM患者在E波峰值时相对于对照组有显著下降,而VVR在正常和病理状况之间保持可比性。在分析的ICM患者中,舒张期VRs在几何学和能量学方面显示出变化。这些紊乱可能归因于影响梗塞壁区域和远端心肌的结构和功能改变。