Performance of electrocardiographic criteria to differentiate Takotsubo cardiomyopathy from acute anterior ST elevation myocardial infarction.

The initial electrocardiogram (ECG) in Takotsubo cardiomyopathy (TC) can mimic an acute, anterior ST-segment elevation myocardial infarction (STEMI). Given the profound and immediate treatment differences between TC and STEMI, it would be clinically valuable to distinguish them using ECG criteria. Presenting ECGs for proven cases of TC and acute, anterior STEMI were retrospectively collected. QRS onset and J-point were manually identified using custom software to compute median ST deviation for each lead. Six published ECG criteria were examined for diagnostic accuracy using the clinical diagnosis as the gold standard. 33 TC and 263 acute, anterior STEMI cases were identified. ST-segment deviation differed significantly between groups for all leads except aVR, I, V5, and V6. All six published ECG criteria showed a marked reduction in diagnostic accuracy in our validation cohort, except for a combination of ST-elevation in leads V2<1.75 mm and V3<2.5 mm (sensitivity 79%, specificity 73% for TC). Our study demonstrates the limited diagnostic accuracy of published ECG rules to distinguish TC from acute, anterior STEMI. Given the rarity of TC and the clinical consequences of a "false positive" TC diagnosis based on ECG criteria alone, such rules should not be used in practice. TC remains a diagnosis of exclusion after emergent angiography in patients with an acute coronary syndrome and significant ST-segment elevation.

Johnson NP ，Chavez JF ，Mosley WJ 2nd ，Flaherty JD ，Fox JM ... -  《-》

Is it possible to differentiate between Takotsubo cardiomyopathy and acute anterior ST-elevation myocardial infarction?

Several studies have investigated the ability of the twelve-lead electrocardiogram (ECG) to reliably distinguish Takotsubo cardiomyopathy (TC) from an acute anterior ST-segment elevation myocardial infarction (STEMI). In these studies, only ECG changes were required - ST-segment deviation and/or T-wave inversion - in TC whereas in acute anterior STEMI, ECGs had to meet STEMI criteria. In the majority of these studies, patients of both genders were used even though TC predominantly occurs in women. The aim of this study is to see whether TC can be distinguished from acute anterior STEMI in a predominantly female study population where all patients meet STEMI-criteria. Retrospective analysis of the ST-segment changes was done on the triage ECGs of 37 patients with TC (34 female) and was compared to the triage ECGs of 103 female patients with acute anterior STEMI. The latter group was divided into the following subgroups: 46 patients with proximal, 47 with mid and 10 with distal LAD occlusion. Three ST-segment based ECG features were investigated: (1) Existing criterion for differentiating anterior STEMI from TC: ST-segment depression >0.5mm in lead aVR+ST-segment elevation ≤1mm in lead V1, (2) frontal plane ST-vector and (3) mean amplitude of ST-segment deviation in each lead. The existing ECG criterion was less accurate (76%) than in the original study (95%), with a large difference in sensitivity (26% vs. 91%). Only a frontal plane ST-vector of 60° could significantly distinguish TC from all acute anterior STEMI subgroups (p<0.01) with an overall diagnostic accuracy of 81%. The mean amplitude in inferior leads II and aVF was significantly higher for patients with TC compared to all patients with acute anterior STEMI (p<0.01 and p<0.05 respectively) and the mean amplitude in the precordial leads V1 and V2 was significantly lower compared to proximal and mid LAD occlusion (p<0.01). Given the consequences of missing the diagnosis of an acute anterior STEMI the diagnostic accuracy of the ECG criteria investigated in this retrospective study were insufficient to reliably distinguish patients with TC from patients with an acute anterior STEMI. To definitely exclude the diagnosis of an acute anterior STEMI coronary angiography, which remains the gold standard, will need to be performed.

Vervaat FE ，Christensen TE ，Smeijers L ，Holmvang L ，Hasbak P ，Szabó BM ，Widdershoven JW ，Wagner GS ，Bang LE ，Gorgels AP ... -  《-》

A new electrocardiographic criterion to differentiate between Takotsubo cardiomyopathy and anterior wall ST-segment elevation acute myocardial infarction.

Several studies have examined the ability of electrocardiography to differentiate between takotsubo cardiomyopathy (TC) and anterior wall acute ST-segment elevation myocardial infarction (AA-STEMI). In those studies, the magnitude of ST-segment elevation was not measured at the J point. The American Heart Association, American College of Cardiology Foundation, and Heart Rhythm Society guidelines recommend that the magnitude of ST-segment elevation should be measured at the J point. Accordingly, the aim of this study was to retrospectively examine whether electrocardiography, using the magnitude of ST-segment elevation measured at the J point, could differentiate 62 patients with TC from 280 with AA-STEMI. Patients with AA-STEMI were divided into following subgroups: 140 with left anterior descending coronary artery occlusions proximal to the first diagonal branch (AA-STEMI-P), 120 with left anterior descending occlusions distal to the first diagonal branch and proximal to the second diagonal branch (AA-STEMI-M), and 20 with left anterior descending occlusions distal to the second diagonal branch (AA-STEMI-D). TC had a much lower prevalence of ST-segment elevation ≥1 mm in lead V(1) (19.4%) compared to AA-STEMI (80.4%, p <0.01), AA-STEMI-P (80.7%, p <0.01), AA-STEMI-M (80%, p <0.01), and AA-STEMI-D (80%, p <0.01). ST-segment elevation ≥1 mm in ≥1 of leads V(3) to V(5) without ST-segment elevation ≥1 mm in lead V(1) identified TC with sensitivity of 74.2% and specificity of 80.6%. Furthermore, this criterion could differentiate TC from each AA-STEMI subgroup, with similar diagnostic values. In conclusion, using the magnitude of ST-segment elevation measured at the J point, a new electrocardiographic criterion is proposed with an acceptable ability to differentiate TC from AA-STEMI.

Tamura A ，Watanabe T ，Ishihara M ，Ando S ，Naono S ，Zaizen H ，Abe Y ，Yano S ，Shinozaki K ，Kotoku M ，Momii H ，Kadokami T ，Kadota J ... -  《-》

Electrocardiogram mimics of acute ST-segment elevation myocardial infarction: insights from cardiac magnetic resonance imaging in patients with tako-tsubo (stress) cardiomyopathy.

Sharkey SW 《-》

Differences in ST-elevation and T-wave amplitudes do not reliably differentiate takotsubo cardiomyopathy from acute anterior myocardial infarction.

Previous efforts to distinguish acute anterior ST-elevation myocardial infarction (anterior-STEMI) from various forms of takotsubo cardiomyopathy (TTC) by electrocardiography (ECG) have produced differing results. We performed a retrospective comparison of acute ECGs between 48 apical and 9 mid-ventricular TTC patients, with 96 anterior-STEMI patients. ECG was recorded in acute phase (<24h from onset of pain), and analyzed for ST-changes, negative T-waves, abnormal Q-waves and QT-interval duration. Time from onset of pain to ECG was gathered from patient records. Anterior-STEMI patients had ST-elevation in lead V1 more frequently than apical (70% vs 15%, p<0.0001) or mid-ventricular TTC patients (70% vs 0%, p<0.0001), and higher ST-elevation amplitudes in leads V2-V5 (p<0.02). Lack of ST-elevation in lead V1 and ST-elevation amplitude <2mm in lead V2 distinguished TTC from anterior-STEMI patients with 63% sensitivity and 93% specificity, with 79% predictive value. In patients with anterior ST-elevation and acute chest pain, lack of ST-elevation in lead V1 and ST-elevation amplitude <2mm in lead V2 suggests a TTC diagnosis. However, this criterion is not reliable enough in clinical practice to distinguish between TTC and anterior-STEMI patients.

Parkkonen O ，Allonen J ，Vaara S ，Viitasalo M ，Nieminen MS ，Sinisalo J ... -  《-》