{Reference Type}: Journal Article {Title}: Simplified echocardiographic assessment of regional left ventricular wall motion pattern in patients with takotsubo and acute coronary syndrome: The Randomized Blinded Two-chamber Apical Kinesis Observation (TAKO) Study. {Author}: Ahmed T;Mangino AA;Lodhi SH;Gupta V;Leung SW;Sorrell VL; {Journal}: Curr Probl Cardiol {Volume}: 0 {Issue}: 0 {Year}: 2024 Jun 28 {Factor}: 16.464 {DOI}: 10.1016/j.cpcardiol.2024.102731 {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.