Predictive Performance of the International Takotsubo Registry Score in the Diagnosis of Takotsubo Syndrome Among Women with Non-ST Segment Elevation Myocardial Infarction

The International Takotsubo Registry (InterTAK) score was developed to assess the probability of takotsubo syndrome (TTS) and to distinguish it from acute coronary syndrome, which has a similar clinical presentation. A European Society of Cardiology (ESC) consensus statement suggests invasive coronary angiography may be deferred in patients with non-ST segment elevation myocardial infarction (NSTEMI) and high probability of TTS. We aimed to determine the predictive performance of the InterTAK score in a real-world population of NSTEMIs. The InterTAK score was retrospectively calculated for consecutive female patients with NSTEMI who underwent invasive coronary angiography at two academic medical centers in New York City from March 2016 to August 2018. Among 375 women with NSTEMI, 15 (4%) had InterTAK score >70, indicating high probability of TTS. Ten (67%) met ESC TTS criteria for a noninvasive strategy, among whom seven had TTS, two had spontaneous coronary artery dissection (SCAD), and one had coronary artery disease requiring revascularization. A total of 48 women (13% of cohort) had a final diagnosis of TTS. The InterTAK score had an area under the receiver operating characteristics curve (AUC) of 0.82 (95% confidence interval, 0.75-0.88) for TTS, with 21% sensitivity and 98% specificity at score >70. In this real-world sample of consecutive female NSTEMI patients, the InterTAK score was predictive of TTS but a high score was rare, and use of the score to obviate invasive angiography could have resulted in delay of revascularization and missed diagnosis of SCAD for a small number of patients. The InterTAK score should be used in conjunction with other clinical variables for angiographic referral.