RESUMEN
OBJECTIVE: Highly sensitive and specific assays of cardiac troponins I and T are the preferred biomarkers in diagnosing myocardial infarction (MI). Assays of cardiac troponin I (cTnI) have been improved with the addition of antibodies against the cTnI molecule and may have increased sensitivity. We hypothesized that a cTnI assay with modern antibody configuration will exhibit equal or better sensitivity in the setting of acute MI compared to cTnT and other markers of myocardial necrosis. MATERIAL AND METHODS: We investigated release kinetics of cTnI (Abbott ADV, Abbott Diagnostics), cTnT (Roche Diagnostics), CKMBmass, myoglobin and heart fatty acid binding protein (H-FABP) in 23 patients admitted with acute ST-segment elevation MI undergoing primary percutaneous coronary intervention. Calibrators for the Abbott ADV cTnI assay are traceable to the United States National Institute of Standards and Technology (NIST) reference material for cTnI. Eleven blood samples were drawn from each patient in the period from admission to 24 h. Biomarkers of necrosis showed marked increases in relative concentrations, especially within the first 2 h after admission. RESULTS: From 30 min after admission onwards, cTnI exhibited significantly higher relative concentrations compared to cTnT, CKMBmass, Myoglobin and H-FABP (p<0.05). CONCLUSIONS: The NIST standardized Abbott TnI ADV assay appears to be more sensitive than cTnT and other biomarkers in the early phase of MI.
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Biomarcadores/sangre , Troponina I/sangre , Humanos , Infarto del Miocardio/sangre , Infarto del Miocardio/diagnóstico , Necrosis , Sensibilidad y EspecificidadRESUMEN
AIM: The aim of this study was to assess the impact of long-term physical training on left ventricular longitudinal contraction by strain rate analysis and tissue tracking imaging. METHODS AND RESULTS: The study population comprised 17 male elite endurance and 15 male elite strength athletes and 12 male control subjects of similar age. Tissue Doppler imaging was recorded in the apical views and used for analysis of the longitudinal systolic myocardial velocity, annular diastolic velocities, strain rate and tissue tracking. Left ventricular mass index was significantly increased in both endurance athletes (209+/-40 g/m(2)) and strength athletes (138+/-38 g/m(2)) compared with normal subjects (96+/-20 g/m(2), P<0.001). Tissue tracking score index and mean strain rate of the 16 segments were significantly increased in strength athletes (7.9+/-1.1 mm and -1.4+/-0.3 s(-1), respectively) compared with endurance athletes (7.5+/-0.9 mm and -1.0+/-0.4 s(-1), P<0.01 for both) and normal subjects (7.4+/-1.0 mm and -1.0+/-0.3 s(-1), P<0.01 for both). CONCLUSION: Despite significant left ventricular hypertrophy and extensive training in elite athletes, we found normal longitudinal left ventricular systolic function, and in strength athletes performing isometric exercise even increased function.