Evaluation of changes of left ventricle energy loss in 4 patients with obstructive hypertrophic cardiomyopathy after modified morrow procedure using vector flow mapping
XU Lei, LIU Li-wen, ZHU Xiao-li, ZHOU Meng-yao
Department of Ultrasound, the First Hospital Affiliated to Air Force Military Medical University, Xi’an 710032, China
Abstract:Objective: To evaluate the changes of left ventricle(LV) energy loss(EL) in patients with obstructive hypertrophic cardiomyopathy(HOCM) after modified morrow procedure by vector flow mapping(VFM), and to analyze the rate of energy dissipation due to blood viscosity from a hemodynamic perspective, and to explore its clinical value in evaluating the operation effect. Methods: The data of four patients with HOCM treated by modified morrow procedure from March 2015 to December 2015 were retrospectively analyzed. Routine echocardiographic parameters were measured before and after surgery, respectively. The standard apical three-chamber dynamic color Doppler images were collected under the VFM mode, and the DSA-RS1 workstation was used for offline analysis, and the EL of LV was calculated frame by frame. The EL mean values of isovolumetric contraction phase, ejection phase, isovolumetric relaxation phase and filling phase were calculated, and the results were the mean values of three cardiac cycles, and the differences were compared before and after the operation. Results: Compared with preoperative condition, echocardiographic parameters: the left ventricular outflow tract(LVOT) diameter and left ventricular end-systolic volume were obviously increased, the LVOT gradient and the thickness of ventricular septum and the proportion of SAM were significantly decreased, the differences were obviously significant(P<0.05). EL value changes: During isovolumetric contraction phase and filling phase, EL mean values were markedly increased in patient 1 and patient 2, markedly decreased in patient 4, and slightly increased in patient 3. During isovolumetric relaxation phase and ejection phase, EL mean values were markedly increased in patient 1 and patient 2 and markedly decreased in patient 3 and patient 4. As a whole the variation trend was that the EL values in patient 1 and patient 2 increased significantly, but decreased significantly in patient 3 and patient 4. Conculsions: After modified morrow procedure, even the normal conditions and echocardiographic parameters were significantly improved in HOCM patients, an increased EL may lead to worse outcomes, EL might be an new index for precise and quantitative assessment of intracardiac blood flow dynamics under different pathophysiology conditions.
徐 磊,刘丽文,朱晓丽,周梦垚. VFM技术评价4例梗阻性肥厚型心肌病患者行改良Morrow术后左室能量损耗变化[J]. 中国临床医学影像杂志, 2018, 29(4): 254-257.
XU Lei, LIU Li-wen, ZHU Xiao-li, ZHOU Meng-yao. Evaluation of changes of left ventricle energy loss in 4 patients with obstructive hypertrophic cardiomyopathy after modified morrow procedure using vector flow mapping. JOURNAL OF CHINA MEDICAL IMAGING, 2018, 29(4): 254-257.
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