Changes of resting cardiac marker levels due to sport adaptation

Background In acute and chronic heart diseases some cardiac necroenzymes and peptide fragments are essential during the diagnosis and following the progression of the diseases. Previous literature data are available about elevation of these cardiac markers after exhausting physical activity, but we do not have information about the resting levels in athletes. Methods In part of the extended cardiology screening of athletes in our institute, we analyzed the levels of hsTroponinT, CKMB, LDH and NT-proBNP from blood samples. All the samples were collected at least 12 hours after the last trainings or competitions. The results of the athletes were compared with a healthy sedentary non-athlete control group. After the blood collection all subject underwent echocardiography examinations and cardiopulmonary exercise testing. Depending on normality, groups were compared with two-tailed Student's t-test or Mann-Whitney U-test. Statistical analysis was processed in RStudio development environment. Results Results of 335 athletes from different sports (male: 162, age: 18.9±5.9 years, training: 15.8±5.9 hours/week) and 53 sedentary non-athletes (male: 23, age: 19.8±3.2 years, training: 2.7±2.3 hours/week) were compared. In athletes, increased level of hsTroponinT was found in 3.3% (n=11), of CKMB in 5.7% (n=18), of LDH in 2.7% (n=9) and of NT-proBNP in 1.2% (n=4). In the control group no elevation was found regarding the CKMB and hsTroponinT, while slightly elevated values of LDH and NT-proBNP were revealed in 1–1 cases. In athletes we measured higher CKMB (17.5±6.8 vs 12.3±3.4 U/l, p<0.001) and LDH values (323.7±63.3 vs 286.0±51.1 U/l, p<0.001), and lower values of NT-proBNP (27.2±29.2 vs 49 8±38.7 pg/ml, p<0.001) compared to the control group, while in the hsTroponinT levels (4.3±1.4 vs 5.6±6.3 ng/l, p=0.33) no significant changes were measured. In term of the examined laboratory parameters significant correlation was found with maximal relative aerob capacity (CKMB: r=0.23, p<0.001; LDH: r=0.18, p<0.001; hsTroponinT: r=0.23, p<0.001; NT-proBNP: r=−0.22, p<0.001), but no correlation was found with age. Significant correlation was found between NT-proBNP levels and echocardiographic measurements of ventricular diameters and left ventricular wall thickness (LVEDD r=−0.15, p<0.03; LVESD r=−0.18, p<0.03; RVD: r=−0.15, p<0.02; IVS: r=−0.22, p<0.001; PWD r=−0.27, p<0.001), CKMB levels correlated with left ventricular wall thickness (IVS: r=0.11, p<0.05; PWD r=0.14, p<0.02). Conclusions Based on our results, in connection with the sports adaptation of the heart, the resting levels of the cardiac markers also show significant changes, these changes are correlated with aerobic endurance and structural sport adaptation parameters as well. Our study draws attention to the importance of different assessment of cardiac markers in athletes. FUNDunding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This project was supported by a grant from the National Research, Development and Innovation Office (NKFIH) of Hungary (K 135076).Supported by the ÚNKP-20-3-I-SE-41 New National Excellence Program of the Ministry for Innovation and Technology from the Source of the National Research, Development and Innovation fund.