Concentration of high-sensitivity cardiac troponin I in the oral fluid in patients with acute myocardial infarction: a pilot study

Aim. To assess the potential of using oral fluid as a non-invasive diagnostic material in patients with myocardial infarction (MI).

Material and methods. The pilot, single-center, prospective study included 47 patients with documented MI, among whom there were 33 men (71%) and 14 women (29%) (mean age, 61,72±12,09 years). All patients successfully treated with reperfusion therapy. The control group consisted of 15 people in whom MI was not confirmed. The concentration of high-sensitivity cardiac tro -ponin I ( hs-cTnI) in blood and oral fluid was determined using chemilumines -cence enzyme immunoassay (CLEIA) on a PATHFAST analyzer (LSI Medience Corporation). Medium sensitivity cardiac troponin I (ms-cTnI) was determined in blood using an Access 2 immunoassay system analyzer (Beckman Coulter, USA). Levels of total bilirubin, creatinine, glucose, rheumatoid factor, alkaline phosphatase and other biochemical parameters were determined on a Furuno CA-400 analyzer (Japan).

Results. The levels of hs-cTnI in patients with MI were significantly higher than in healthy patients both in blood (8,73±1,17 ng/ml vs 0,012±0,03 ng/ml, p<0,001) and oral fluid (0,41±0,11 ng/ml vs 0,004±0,001 ng/ml, p<0,001). In patients with-AMI, there was a moderate correlation between the concentration of hs-cTnI in the serum and the oral fluid (r=0,319; p<0,05).

The serum level of hs-cTnI in patients with Q-wave (n=33) and non-Q-wave (n=14) MI was 10,11±1,53 ng/ ml vs 5,48±1,29 ng/ml, respectively (p=0,025). The oral fluid concentration of hs-cTnI in patients with W-wave (n=33) and non-Q-wave (n=14) MI was 0,42±0,14 ng/ml vs 0,40±0,16 ng/ml, respectively (p=0,925).

The serum level of hs-cTnI in anterior MI (n=19) was 8,92±2,06 ng/ml vs 8,91±1,81 ng/ml in posterior one (n=23) (p=0,997). The concentration of hs-cTnI in the oral fluid was 0,21±0,06 ng/ml vs 0,57±0,21 ng/ml, respectively (p=0,107).

The oral fluid concentrations of hs-TnI in patients with MI using conventional plastic tubes (n=26) and special Sarstedt microtubes (n=21) were 0,56±0,19 ng/ml and 0,22±0,10 ng/ml, respectively (p=0,12).

Conclusion. This pilot study has proven the possibility of detecting hs-cTnI in the oral fluid of patients with MI. There was a moderate correlation between the level of hs-cTnI in blood serum and oral fluid. Further research is needed to determine the hs-cTnI reference values in the oral fluid of patients with MI.

1. Thygesen K, Alpert J, Jaffe A, et al. Fourth universal definition of myocardial infarction (2018). Eur Heart J. 2019;40(3):237-69. doi:10.1093/eurheartj/ehy462

2. Chaulin AM, Karslyan LS, Grigoriyeva EV, et al. Clinical and Diagnostic Value of Cardiac Markers in Human Biological Fluids. Kardiologiia. 2019;59(11):66-75. (In Russ.) doi:10.18087/cardio.2019.11.n414.

3. Lee JM, Garon E, Wong DT. Salivary diagnostics. Orthod Craniofac Res. 2009;12(3):206-11. doi:10.1111/j.1601-6343.2009.01454.x.

4. Vavilova TP, Yanushevich OO, Ostrovskaya IG. Saliva. Analytical capabilities and prospects. M.: BINOM, 2014. p. 312. (In Russ.) ISBN: 978-5-9518-0577-5.

5. Humphrey SP, Williamson RT. A review of saliva: normal composition, flow, and function. J Prosthet Dent. 2001;85(2):162-9. doi:10.1067/mpr.2001.113778.

6. Foley JD 3rd, Sneed JD, Steinhubl SR, et al. Oral fluids that detect cardiovascular disease biomarkers. Oral Surg Oral Med Oral Pathol Oral Radiol. 2012;114(2):207-14. doi:10.1016/j.oooo.2012.03.003.

7. Floriano PN, Christodoulides N, Miller CS, et al. Use of saliva-based nano-biochip tests for acute myocardial infarction at the point of care: a feasibility study. Clin Chem. 2009;55(8):1530-8. doi:10.1373/clinchem.2008.117713.

8. Miller CS, Foley JD, Bailey AL, et al. Current developments in salivary diagnostics. Biomark Med. 2010;4(1):171-189. doi:10.2217/bmm.09.68

9. Mirzaii-Dizgah I, Riahi E. Salivary troponin I as an indicator of myocardial infarction. Indian J Med Res. 2013;138(6):861-5.

10. Mirzaii-Dizgah I, Riahi E. Salivary high-sensitivity cardiac troponin T levels in patients with acute myocardial infarction. Oral Dis. 2013;19(2):180-4. doi:10.1111/j.1601-0825.2012.01968.x.

11. Chia S, Senatore F, Raffel OC, et al. Utility of cardiac biomarkers in predicting infarct size, left ventricular function, and clinical outcome after primary percutaneous coronary intervention for ST-segment elevation myocardial infarction. JACC Cardiovasc Interv. 2008;1(4):415-23. doi:10.1016/j.jcin.2008.04.010.

12. Dubin RF, Li Y, He J, et al. Predictors of high sensitivity cardiac troponin T in chronic kidney disease patients: a cross-sectional study in the chronic renal insufficiency cohort (CRIC). BMC Nephrol. 2013;14:229. doi:10.1186/1471-2369-14-229.

13. Ziebig R, Lun A, Hocher B, et al. Renal elimination of troponin T and troponin I. Clin Chem. 2003;49(7):1191-3. doi:10.1373/49.7.1191

14. Pervan P, Svagusa T, Prkacin I, et al. Urine high-sensitive troponin I measuring in patients with hypertension. Signa Vitae. 2017;13(3):62-4. doi:10.22514/SV133.062017.13.

15. Chen JH, Inamori-Kawamoto O, Michiue T, et al. Cardiac biomarkers in blood, and pericardial and cerebrospinal fluids of forensic autopsy cases: A reassessment with special regard to postmortem interval. Leg Med (Tokyo). 2015;17(5):343-50. doi:10.1016/jlegalmed.2015.03.007.