Abstract：
BACKGROUND: Differentiating Takotsubo cardiomyopathy (TTC) from acute coronary syndrome involving the left anterior descending coronary artery (LAD-ACS) is difficult due to left ventricular apical wall motion abnormality pattern in both and typically requires an invasive coronary angiography (ICA) study for diagnostic confirmation.
OBJECTIVE: To identify differences in the regional wall motion abnormality (RWMA) pattern using a comprehensive comparative analysis of the transthoracic echocardiographic (TTE) findings in patients with TTC versus LAD-ACS.
METHODS: This was a retrospective, randomized, blinded comparison study including a derivation cohort of 105 patients with TTC (N=52) or LAD-ACS (N=53) with concomitant TTE and ICA identified from our institutional database. A comprehensive echocardiographic wall motion analysis was performed (unblinded) to search for subtle differences in RWMA patterns by marking the exact locations of the end-systolic hinge points (HP) - defined as the intersection between the normal and abnormal regional myocardial thickening - in all apical views. The HP location relative to mitral annulus in each apical view was compared for symmetry and the apical 2-chamber (A2C) view was identified as having the most consistent, quantitative difference between TTC and LAD-ACS. This A2C quantitative model was then prospectively studied in a randomized, blinded, validation cohort of 30 subjects with either TTC or LAD-ACS by eight echocardiographic readers with all levels of clinical experience.
RESULTS: In the unblinded derivation cohort, the A2C view showed that the ratio (1.02) and the absolute distance between the anterior HP (3.57 cm) and the inferior HP (3.53 cm) in TTC was significantly different than the ratio (0.761) and the absolute differences between the AHP (4.5 cm) and the IHP (5.93 cm) in LAD-ACS. An AHP: IHP of 0.96 for men and 0.84 for women was able to correctly categorize 84.8% of male and 91.7% of female patients. When applied to the validation cohort, the model showed fairly accurate results with a 74% prediction rate in diagnosing TTC in female patients.
CONCLUSIONS: We propose a relatively simple 2-D TTE diagnostic tool emphasizing subtle differences in the RWMA pattern in the A2C view alone as a semi-quantitative imaging parameter to help differentiate TTC from LAD-ACS.
OBJECTIVE: To identify differences in the regional wall motion abnormality (RWMA) pattern using a comprehensive comparative analysis of the transthoracic echocardiographic (TTE) findings in patients with TTC versus LAD-ACS.
METHODS: This was a retrospective, randomized, blinded comparison study including a derivation cohort of 105 patients with TTC (N=52) or LAD-ACS (N=53) with concomitant TTE and ICA identified from our institutional database. A comprehensive echocardiographic wall motion analysis was performed (unblinded) to search for subtle differences in RWMA patterns by marking the exact locations of the end-systolic hinge points (HP) - defined as the intersection between the normal and abnormal regional myocardial thickening - in all apical views. The HP location relative to mitral annulus in each apical view was compared for symmetry and the apical 2-chamber (A2C) view was identified as having the most consistent, quantitative difference between TTC and LAD-ACS. This A2C quantitative model was then prospectively studied in a randomized, blinded, validation cohort of 30 subjects with either TTC or LAD-ACS by eight echocardiographic readers with all levels of clinical experience.
RESULTS: In the unblinded derivation cohort, the A2C view showed that the ratio (1.02) and the absolute distance between the anterior HP (3.57 cm) and the inferior HP (3.53 cm) in TTC was significantly different than the ratio (0.761) and the absolute differences between the AHP (4.5 cm) and the IHP (5.93 cm) in LAD-ACS. An AHP: IHP of 0.96 for men and 0.84 for women was able to correctly categorize 84.8% of male and 91.7% of female patients. When applied to the validation cohort, the model showed fairly accurate results with a 74% prediction rate in diagnosing TTC in female patients.
CONCLUSIONS: We propose a relatively simple 2-D TTE diagnostic tool emphasizing subtle differences in the RWMA pattern in the A2C view alone as a semi-quantitative imaging parameter to help differentiate TTC from LAD-ACS.
摘要：
背景：区分Takotsubo心肌病（TTC）和累及左前降支的急性冠脉综合征（LAD-ACS）是困难的，因为两者都存在左心室心尖壁运动异常模式，通常需要进行侵入性冠状动脉造影（ICA）研究以进行诊断确认。
目的：通过对TTC和LAD-ACS患者的经胸超声心动图（TTE）结果进行综合比较分析，确定局部室壁运动异常（RWMA）模式的差异。
方法：这是一个回顾性研究，随机化，盲性比较研究包括从我们的机构数据库中确定的105例TTC(N=52)或LAD-ACS(N=53)合并TTE和ICA患者的衍生队列.进行了全面的超声心动图壁运动分析（非盲），以通过标记收缩末期铰链点（HP）的确切位置来搜索RWMA模式的细微差异-定义为正常和异常区域心肌增厚之间的交点-在所有根尖视图中。比较了每个心尖视图中相对于二尖瓣环的HP位置的对称性，并且认为心尖2腔（A2C）视图具有最一致的，TTC和LAD-ACS之间的定量差异。然后在随机的情况下前瞻性地研究了A2C定量模型，失明,由8位具有所有临床经验水平的超声心动图阅读器对30位TTC或LAD-ACS受试者进行验证队列。
结果：在非盲派生队列中，A2C视图显示，TTC中前HP（3.57cm）和下HP（3.53cm）之间的比率（1.02）和绝对距离与LAD-ACS中的AHP（4.5cm）和IHP（5.93cm）之间的比率（0.761）和绝对差异显着。AHP：男性为0.96，女性为0.84，能够正确分类84.8％的男性患者和91.7％的女性患者。当应用于验证队列时，该模型显示了相当准确的结果,在女性患者中诊断TTC的预测率为74%.
结论：我们提出了一种相对简单的二维TTE诊断工具，强调仅A2C视图中RWMA模式的细微差异，作为半定量成像参数，以帮助区分TTC和LAD-ACS。
目的：通过对TTC和LAD-ACS患者的经胸超声心动图（TTE）结果进行综合比较分析，确定局部室壁运动异常（RWMA）模式的差异。
方法：这是一个回顾性研究，随机化，盲性比较研究包括从我们的机构数据库中确定的105例TTC(N=52)或LAD-ACS(N=53)合并TTE和ICA患者的衍生队列.进行了全面的超声心动图壁运动分析（非盲），以通过标记收缩末期铰链点（HP）的确切位置来搜索RWMA模式的细微差异-定义为正常和异常区域心肌增厚之间的交点-在所有根尖视图中。比较了每个心尖视图中相对于二尖瓣环的HP位置的对称性，并且认为心尖2腔（A2C）视图具有最一致的，TTC和LAD-ACS之间的定量差异。然后在随机的情况下前瞻性地研究了A2C定量模型，失明,由8位具有所有临床经验水平的超声心动图阅读器对30位TTC或LAD-ACS受试者进行验证队列。
结果：在非盲派生队列中，A2C视图显示，TTC中前HP（3.57cm）和下HP（3.53cm）之间的比率（1.02）和绝对距离与LAD-ACS中的AHP（4.5cm）和IHP（5.93cm）之间的比率（0.761）和绝对差异显着。AHP：男性为0.96，女性为0.84，能够正确分类84.8％的男性患者和91.7％的女性患者。当应用于验证队列时，该模型显示了相当准确的结果,在女性患者中诊断TTC的预测率为74%.
结论：我们提出了一种相对简单的二维TTE诊断工具，强调仅A2C视图中RWMA模式的细微差异，作为半定量成像参数，以帮助区分TTC和LAD-ACS。
