‘GET QT’: Clinical Criteria to Differentiate Takotsubo Cardiomyopathy from STEMI

• Main Authors: Gaurang Nandkishor Vaidya, Abhishek Jaiswal, Bhaskara Madhira
• Format: Article
• Language: English
• Published: Barcaray International 2016-01-01
• Series: International Cardiovascular Forum Journal
• Subjects: Myocardial infarction; Takotsubo cardiomyopathy; ST-elevation; EKG; cardiac biomarkers; echocardiography
• Online Access: http://icfjournal.org/index.php/icfj/article/view/324/pdf-2
• ISSN: 2410-2636; 2409-3424

Background: Introduction: Presentation of Takotsubo cardiomyopathy (TCM) may closely mimic ST-elevation myocardial infarction (STEMI) and clinicians are often faced with a dilemma when cardiac catheterization is unavailable or contraindicated. Methods Age-matched 42 TCM and 55 STEMI patients admitted in SUNY Upstate Hospital, Syracuse, NY were retrospectively compared for characteristics at presentation. Results Results: 12 TCM patients (26%) had ST elevation in the initial EKG. Mean QTc interval was significantly prolonged in TCM (469ms vs 443ms,p=0.001). The peak Troponin T (TnTp) level in TCM was significantly less (1.15ng/ml vs 6.04ng/ml; p=0.001) and the time to peak troponin T (Tp) was lower (3.7 hours versus 12.4 hours,p=0.001). Mean LV ejection fraction (EF) was 36% in TCM versus 47.4% in STEMI (p=0.001). Significance (p<0.05) was noted for 5 predictors on multiple regression namely: Gender, EF, TnTp, QTc interval and Tp. A prediction model was then developed, giving a score of one for each positive finding: female gender, EF< 40%, TnTp< 2ng/ ml, QTc> 470ms in the initial EKG and Tp< 6 hours (GET QT criteria). The presence of 3 or more predictors had a sensitivity of 88.8%, specificity of 95.1% and negative predictive value of 90.9% to diagnose TCM. Though there have been recent publications proposing various criteria to distinguish the two diseases, this is the first proposing highly specific and all-inclusive combined laboratory, EKG and echocardiography criteria. Conclusions Females with early and low peaking troponins prolonged QTc; low EF were likely to have TCM. With the proposed prediction modelpresence of 3 or more factors is highly specific to diagnose TCM.