ECG Criteria to Differentiate Between Takotsubo (Stress) Cardiomyopathy and Myocardial Infarction

Abstract

Background: ECG criteria differentiating Takotsubo cardiomyopathy (TTC) from mainly anterior myocardial infarction (MI) have been suggested; however, this was in small patient populations.

Methods and results: Twelve-lead admission ECGs of consecutive 200 TTC and 200 MI patients were compared in dichotomized groups based on the presence or absence of ST-elevation MI (STEMI versus STE-TTC and non-ST elevation MI versus non ST-elevation-TTC). When comparing STEMI and STE-TTC, ST-elevation in -aVR was characteristic of STE-TTC with a sensitivity/specificity of 43% and 95%, positive predictive value (PPV) 91%, and a negative predictive value (NPV) 62% (P<0.001); when ST-elevation in -aVR is accompanied by ST-elevation in inferior leads, sensitivity/specificity were 14% and 98% (PPV was 89% and NPV 52%) (P=0.001), and 12% and 100% when associated with ST-elevation in anteroseptal leads (PPV 100%, NPV 52%) (P<0.001). On the other hand, STEMI was characterized by ST-elevation in aVR (sensitivity/specificity of 31% and 95% P<0.001, PPV 85% and NPV 59%) and ST-depression in V2-V3-V4 (sensitivity/specificity of 24% and 100% P<0.001, PPV 100% and NPV 76%). When comparing non-ST elevation MI and non ST-elevation-TTC, T-inversion in leads I-aVL-V5-V6 had a sensitivity/specificity of 17% and 97% for non ST-elevation-TTC (PPV 83% and NPV 55%) (P<0.001), and ST-elevation in -aVR with T-inversion in any lead was also specific for non ST-elevation-TTC (sensitivity/specificity of 8% and 100%, PPV 100% and NPV 53%) (P=0.006). In non-ST elevation MI patients, the presence of ST-depression in V2-V3 was specific (sensitivity/specificity of 11% and 99%, PPV 91% and NPV 51%) (P=0.01).

Conclusions: ECG on admission can differentiate between TTC and acute MI, with high specificity and positive predictive value.

Clinical trial registration: URL: https://www.clinicaltrials.gov/. Unique identifier: NCT01947621.

Keywords: Takotsubo cardiomyopathy; differential diagnosis; electrocardiogram; myocardial infarction; stress‐induced cardiomyopathy.

Figure 1

Comparison of 1—ST‐elevation, 2—ST‐depression, and 3—T‐wave inversion in 12‐lead ECG between Takotsubo cardiomyopathy and myocardial infarction in the setting of STEMI and NSTEMI presentation. ACS indicates acute coronary syndromes; MI, myocardial infarction; NSTEMI, non ST‐elevation MI; STEMI, ST‐elevation MI.

Figure 2

Algorithm favoring the diagnosis of Takotsubo based on highly specific admission ECG criteria in the setting of acute coronary syndrome (STEMI and NSTEMI). NSTEMI indicates non ST‐elevation myocardial infarction; STEMI, ST‐elevation myocardial infarction; STe, ST‐segment elevation; STd, ST‐segment depression; TTC, Takotsubo cardiomyopathy. *100% specificity and 100% positive predictive value; ^†More than 2 leads out of 3 in II‐III‐aVF; ^‡More than 4 leads out of 6 in (V1‐V2‐V3‐V4‐V5‐V6); ^xMore than 2 leads out of 3 in (V1‐V2‐V3).

Figure 3

ECG examples for the most specific combination of criteria in each group of patients. Group 1: Takotsubo with ST‐elevation (STE‐TTC): STe in –aVR and STe in anteroseptal lead; Group 2: ST‐elevation myocardial infarction (STEMI): STd in V2, V3 and V4 (among others); Group 3: Takotsubo without ST‐elevation (NSTE‐TTC): STe in –aVR and Tinv (any lead); Group 4: Non ST‐elevation myocardial infarction (NSTEMI): STd in V2, V3.