BACKGROUND Aortic regurgitation (AR) and subclinical left ventricular (LV) dysfunction expressed by myocardial deformation imaging are common in patients with transposition of the great arteries after the arterial switch operation (ASO). Echocardiographic evaluation is often hampered by reduced acoustic window settings. Cardiovascular magnetic resonance (CMR) imaging provides a robust alternative as it allows for comprehensive assessment of degree of AR and LV function. The purpose of this study is to validate CMR based 4-dimensional flow quantification (4D flow) for degree of AR and feature tracking strain measurements for LV deformation assessment in ASO patients. METHODS A total of 81 ASO patients (median 20.6 years, IQR 13.5-28.4) underwent CMR for 4D and 2D flow analysis. CMR global longitudinal strain (GLS) feature tracking was compared to echocardiographic (echo) speckle tracking. Agreements between and within tests were expressed as intra-class correlation coefficients (ICC). RESULTS Eleven ASO patients (13.6%) showed AR > 5% by 4D flow, with good correlation to 2D flow assessment (ICC = 0.85). 4D flow stroke volume of the aortic valve demonstrated good agreement to 2D stroke volume over the mitral valve (internal validation, ICC = 0.85) and multi-slice planimetric LV stroke volume (external validation, ICC = 0.95). 2D flow stroke volume showed slightly less, though still good agreement with 4D flow (ICC = 0.78) and planimetric LV stroke volume (ICC = 0.87). GLS by CMR was normal (- 18.8 ± 4.4%) and demonstrated good agreement with GLS and segmental analysis by echocardiographic speckle tracking (GLS = - 17.3 ± 3.1%, ICC of 0.80). CONCLUSIONS Aortic 4D flow and CMR feature tracking GLS analysis demonstrate good to excellent agreement with 2D flow assessment and echocardiographic speckle tracking, respectively, and can therefore reliably be used for an integrated and comprehensive CMR analysis of aortic valve competence and LV deformation analysis in ASO patients.

中文翻译：

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动脉切换手术后患者的主动脉瓣4D流量分析和由心血管磁共振引起的心肌变形的验证。

背景技术由心肌变形成像表达的主动脉瓣关闭不全（AR）和亚临床左心室（LV）功能障碍在动脉转换手术（ASO）后发生大动脉移位的患者中很常见。超声心动图评估通常受到声音窗口设置降低的困扰。心血管磁共振（CMR）成像提供了一种强大的替代方法，因为它可以全面评估AR和LV功能的程度。这项研究的目的是验证ASO患者基于AR程度的CMR 4维流定量（4D流）和特征跟踪应变测量，以评估LV变形。方法总共81例ASO患者（中位数20.6岁，IQR 13.5-28.4）接受了CMR进行4D和2D血流分析。将CMR总纵向应变（GLS）特征跟踪与超声心动图（回声）斑点跟踪进行了比较。测试之间和测试内部的一致性表示为类内相关系数（ICC）。结果11例ASO患者（13.6％）通过4D血流显示AR> 5％，与2D血流评估具有良好的相关性（ICC = 0.85）。主动脉瓣的4D流量冲程体积与二尖瓣的2D冲程体积（内部验证，ICC = 0.85）和多层平面LV冲程体积（外部验证，ICC = 0.95）显示出良好的一致性。尽管与4D流量（ICC = 0.78）和平面LV行程量（ICC = 0.87）仍然很吻合，但2D流量的冲程量略有减少。CMR的GLS正常（-18.8±4.4％），与GLS和通过超声心动图斑点跟踪进行的分段分析显示出良好的一致性（GLS =-17。3±3.1％，ICC为0.80）。结论主动脉4D血流和CMR特征跟踪GLS分析分别与2D血流评估和超声心动图斑点跟踪具有良好的一致性，因此可以可靠地用于ASO患者的主动脉瓣功能和LV变形分析的综合和综合CMR分析。