We aimed to find association of telomere length and telomerase activity in circulating leukocytes and thromboaspirates of patients with acute myocardial infarction (AMI). Furthermore, association of telomere-telomerase system with oxidative stress markers was tested.

Material and methods:
Leukocyte telomere length, telomerase activity and scores related to oxidative-stress status (Protective, Damage and OXY) were evaluated.

Patients were divided into: stabile angina pectoris (AP) (n=22), AMI with: ST-segment elevation (STEMI) (n=93), non-obstructive coronary arteries (MINOCA) (n=7), blood vessel rupture (n=6) in three time points, and compared to with 84 healthy subjects. Telomerase activity was significantly higher in all CAD sub-groups compared to the control group [AP=0.373 (0.355-0.386), STEMI=0.375 (0.349-0.395), MINOCA=0.391 (0.366-0.401), blood vessel rupture=0.360 (0.352-0.385) vs CG=0.069 (0.061-0.081), p=0.000], while telomeres were significantly shorter in STEMI, MINOCA and blood vessel rupture compared to the control group [STEMI=1.179 (0.931-1.376), MINOCA=1.026 (0.951-1.070), blood vessel rupture=1.089 (0.842-1.173) vs CG=1.329 (1.096-1.624), p=0.030]. Values of OXY score were significantly higher in STEMI and MINOCA patients compared to control group and AP patients [5.83 (4.55-7.54) and 10.28 (9.19-10.72) vs 4.94 (3.29-6.18) and 4.18 (2.58-4.86), p=0.000]. Longer telomeres and higher telomerase activity were found in thromboaspirates, compared to peripheral blood leukocytes in the same patients [1.25 (1.01 - 1.84) vs 1.18 (0.909 - 1.516), p=0.036; and 0.366 (0.367 - 0.379) vs 0.366 (0.367 - 0.379), p=0.000, respectively]. Telomere length and telomerase activity had good diagnostic ability to separate STEMI patients from controls.

Leukocyte telomere length and telomerase activity can differentiate CAD patients from healthy persons, and relate CAD to oxidative stress.