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Background: Cardiac troponins are routinely used as markers of myocardial damage. Originally, they were only intended for use in diagnosing acute coronary syndromes; however, we now know that raised serum troponin levels are not always caused by ischemia. There are many other clinical conditions that cause damage to cardiomyocytes, leading to raised levels of troponin. However, the specificity of cardiac troponins towards the myocardium is absolute. Our work focuses on mechanical damage to the myocardium and on monitoring the factors that raise the levels of cardiospecific markers after primo-implantation of a pacemaker with an actively fixed electrode. Aims: (i) To determine whether the use of a primo-implanted pacemaker with an electrode system with active fixation will raise troponin levels over baseline. (ii) To assess whether troponin I elevation is dependent on procedure complexity. Methods: We enrolled 219 consecutive patients indicated for pacemaker primo-implantation; cardiospecific marker values (troponin I, CKMB, myoglobin) were determined before the implantation procedure and again at 6- and 18-h intervals after the procedure. We monitored duration of cardiac skiascopy, number of attempts to place the electrode (active penetration into the tissue) and intervention range (single-chamber versus dual-chamber pacing), and we assessed the clinical data. Results: The average age of the enrolled patients was 78.2 ± 8.0 years (median age, 80 years); women constituted 45% of the group. We implanted 128 dual-chamber and 91 single-chamber devices with an average skiascopic time of 38.6 ± 22.0 s (median, 33.5 s). Troponin I serum levels increased from an initial 0.03 ± 0.07 μg/L (median, 0.01) to 0.18 ± 0.17 μg/L (median, 0.13) and 0.09 ± 0.18 μg/L (median, 0.04) at 6 and 18 h, respectively. The differences were statistically significant (P < 0.001 or P < 0.001). We confirmed a correlation between troponin increase and duration of skiascopy (P < 0.001). We also demonstrated a correlation between increased troponin I and number of attempts to place a pacemaker electrode (penetration into the tissue) at 6 h (P < 0.001) post-implantation. Conclusion: We detected slightly elevated troponin I levels in patients with primo-implanted pacemakers using electrodes with active fixation. We demonstrated a direct correlation between myocardial damage (number of electrode penetrations into the myocardium) and troponin I elevation, as well as between complexity (severity) of the implantation procedure (indicated by prolonged skiascopy) and raised troponin I. The described phenomenon demonstrates the loss of the diagnostic role of troponin I early after pacemaker primo-implantation in patients with concomitant chest pain.

Aim To verify and compare the accuracies of mortality predictions in the Intensive Care Unit (ICU) of the Internal Clinic of Central Military Hospital in Prague, Czech Republic, using model APACHE II and the newer systems of the APACHE IV, SAPS 3 and MPMoIII. Methods The data were collected retrospectively between 2011 and 2012, 1000 patients were evaluated. The assessment of the overall accuracy of the mortality predictions was performed using the standardized mortality ratio (SMR), and the calibration was assessed using the Lemeshow-Hosmer “goodness-of-fit” C statistic. Discrimination was evaluated using ROC curves based on calculations of the areas under the curve (AUCs). Results The APACHE II, SAPS 3, and MPMoIII systems significantly overestimated the expected mortality, whereas the APACHE IV model led to correct estimations of the overall mortality. The discrimination capabilities of the models assessed according to the constructions of the ROC curves were evaluated as good, only the APACHE II was evaluated as satisfactory. The calibrations of all models were evaluated as unsatisfactory. Conclusion The best mortality estimation for the investigated population sample was provided by the APACHE IV system. The discrimination capabilities of all models for the studied population were satisfactory, but the calibration of all of the systems was unsatisfactory. The conclusions of our study are limited by the relatively small size of the investigated sample and the fact that this study was conducted at only a single site.