title: Serial High-Sensitivity Troponin T in Post-Primary Angioplasty Exercise Test.
abstract: BACKGROUND
  The kinetics of high-sensitivity troponin T (hscTnT) release should be studied in different situations, including functional tests with transient ischemic abnormalities.
  
  
  OBJECTIVE
  To evaluate the release of hscTnT by serial measurements after exercise testing (ET), and to correlate hscTnT elevations with abnormalities suggestive of ischemia.
  
  
  METHODS
  Patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing primary angioplasty were referred for ET 3 months after infarction. Blood samples were collected to measure basal hscTnT immediately before (TnT0h), 2 (TnT2h), 5 (TnT5h), and 8 hours (TnT8h) after ET. The outcomes were peak hscTnT, TnT5h/TnT0h ratio, and the area under the blood concentration-time curve (AUC) for hscTnT levels. Log-transformation was performed on hscTnT values, and comparisons were assessed with the geometric mean ratio, along with their 95% confidence intervals. Statistical significance was assessed by analysis of covariance with no adjustment, and then, adjusted for TnT0h, age and sex, followed by additional variables (metabolic equivalents, maximum heart rate achieved, anterior wall STEMI, and creatinine clearance).
  
  
  RESULTS
  This study included 95 patients. The highest geometric means were observed at 5 hours (TnT5h). After adjustments, peak hscTnT, TnT5h/TnT0h and AUC were 59% (p = 0.002), 59% (p = 0.003) and 45% (p = 0.003) higher, respectively, in patients with an abnormal ET as compared to those with normal tests.
  
  
  CONCLUSIONS
  Higher elevations of hscTnT may occur after an abnormal ET as compared to a normal ET in patients with STEMI.
authors.affiliation: Fundação Universitária de Cardiologia, Instituto de Cardiologia, Porto Alegre, RS, Brazil.
authors.forename: Humberto Andres
authors.initials: HA
authors.lastname: Vaz
authors.affiliation: Fundação Universitária de Cardiologia, Instituto de Cardiologia, Porto Alegre, RS, Brazil.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Vanz
authors.affiliation: Fundação Universitária de Cardiologia, Instituto de Cardiologia, Porto Alegre, RS, Brazil.
authors.forename: Iran
authors.initials: I
authors.lastname: Castro
mesh_terms: D000328:Adult; D000368:Aged; D017130:Angioplasty; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood; D003430:Cross-Sectional Studies; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012307:Risk Factors; D000072657:ST Elevation Myocardial Infarction / Q000097:blood* / Q000175:diagnosis; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D013997:Time Factors; D020107:Troponin T / Q000097:blood*
chemical_list: D015415:Biomarkers; D020107:Troponin T