High-sensitivity troponin T for prediction of left ventricular function and infarct size one year following ST-elevation myocardial infarction

BACKGROUND

Data relating high-sensitivity cardiac troponin T (hs-cTnT) to long-term myocardial function and infarct size in patients after ST-elevation myocardial infarction (STEMI) are lacking. We aimed to evaluate the use of early hs-cTnT concentrations for prediction of myocardial function and infarct size assessed by cardiac magnetic resonance imaging (CMR) one year following STEMI.

METHODS

Sixty-six patients, revascularized by primary percutaneous coronary intervention (PCI) for first-time STEMI, were enrolled in this observational study. Serial hs-cTnT, creatine kinase (CK), high-sensitivity C-reactive protein (hs-CRP) and lactate dehydrogenase (LDH) levels were measured on admission, 6 h, 12 h, and 24 h post-PCI. Patients underwent CMR within the first week and 12months thereafter.

RESULTS

Except for admission hs-cTnT, all single time point and peak hs-cTnT concentrations showed significant correlations with left ventricular ejection fraction (LVEF: r=-0.404 to -0.517, all ps<0.01) and infarct size (IS: r=0.421 to 0.700, all ps<0.01) at baseline and follow-up. The area under the curve (AUC) of peak hs-cTnT was 0.82 (95% CI 0.71-0.92) for the prediction of decreased LVEF (<55%) and 0.89 (95% CI 0.81-0.97) for the prediction of large IS (>8%) at 12months. The combination of all four biomarkers resulted in an AUC of 0.82 and 0.92 for the prediction of reduced LVEF and large IS at 12months, respectively (both ps>0.05).

CONCLUSION

In stable STEMI patients successfully revascularized by primary PCI, serial and peak concentrations of hs-cTnT are closely correlated to long-term LVEF and IS. Combination of hs-cTnT with CK, hs-CRP, or LDH did not add any significant prognostic value as compared with hs-cTnT alone.

Importance of ventricular function in the election of electro heart mode

The integration of the ventricular function is essential when making decisions over a patient subjected to cardiac electrostimulation in order to understand the structure followed in the new cardiac stimulation and resynchronising therapy guides. To support the importance of ventricular function in cardiac electrostimulation it is important to know: (i)the deleterious effect of stimulation on the right ventricle apex; (ii)the effect over the left ventricular function produced by complete blockage of the left branch, and (iii)left ventricular disfunction as arrythmogenic substrate. When it comes to decide what type of cardiac electrostimualtion to apply we will know: the percentage of ventricular stimulation needed and its ventricular function. A normal ventricular function will enable electrostimulation from the right ventricle apex or alternative site. On the contrary, if this value is lower than 50% the most recommended electrostimulation is cardiac resynchronisation (CRT-P), which will be accompanied by defibrillation (CRT-D) if FEVI is lower than 35%.