title: Diagnostic utility of cardiac biomarkers in discriminating Takotsubo cardiomyopathy from acute myocardial infarction.
abstract: Background: Takotsubo cardiomyopathy (TC) mimics acute myocardial infarction (AMI). We postulated that ventricular dysfunction in TC in the absence of significant myocardial necrosis would produce higher B-type natriuretic peptide (BNP)/troponin T (TnT) and BNP/creatine kinase MB fraction (CKMB) ratios than in AMI.Methods and Results: We studied 58 consecutive TC (age 65.8 +/- 12.9) and 97 AMI patients (age 59.8 +/-13.4). The ratios of BNP/TnT and BNP/CKMB were calculated with the use of first simultaneously drawn laboratory values. Receiver operating characteristic curves were used to distinguish TC from AMI with 95% specificity based on cardiac biomarker ratios. Median BNP/TnT and BNP/CKMB ratios were, respectively,1,292 [interquartile range 443.4-2,657.9] and 28.44 [13.7-94.8] in the TC group and 226.9[69.91-426.32] and 3.63 [1.07-10.02] in the AMI group (P <.001). TC can be distinguished from AMI with 95% specificity with the use of BNP/TnT ratio ≥1,272 (sensitivity 52%) and BNP/CKMB ratio ≥29.9 (sensitivity 50%).Conclusions: The value of BNP is significantly higher in TC than in AMI. Early BNP/TnT and BNP/CKMB ratios help to differentiate TC from AMI with greater accuracy than BNP alone.
authors.affiliation: Department of Internal Medicine, Cleveland Clinic, Cleveland, Ohio
authors.forename: Mandeep Singh
authors.initials: MS
authors.lastname: Randhawa
authors.forename: Ashwat Singh
authors.initials: AS
authors.lastname: Dhillon
authors.forename: Harris C
authors.initials: HC
authors.lastname: Taylor
authors.forename: Zhiyuan
authors.initials: Z
authors.lastname: Sun
authors.forename: Milind Y
authors.initials: MY
authors.lastname: Desai
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D015331:Cohort Studies; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000175:diagnosis*; D020097:Natriuretic Peptide, Brain / Q000097:blood; D012189:Retrospective Studies; D054549:Takotsubo Cardiomyopathy / Q000097:blood* / Q000175:diagnosis*; D020107:Troponin T / Q000097:blood
chemical_list: D015415:Biomarkers; D020107:Troponin T; D020097:Natriuretic Peptide, Brain