Exercise-induced cardiac troponin release in athletes with versus without coronary atherosclerosis

BACKGROUND: The magnitude of exercise-induced cardiac troponin (cTn) elevations is dependent on cardiovascular health status, and previous studies have shown that occult coronary atherosclerosis is highly prevalent among amateur athletes. We tested the hypothesis that middle-aged and older athletes with coronary atherosclerosis demonstrate greater cTn elevations following a controlled endurance exercise test compared to healthy peers. METHODS: We included 59 male athletes from the MARC-2 study and stratified them as controls (coronary artery calcium score (CACS) = 0, n=20), high CACS (≥300 Agatston Units or ≥75th MESA percentile, n=20) or significant stenosis (≥50% in any coronary artery, n=19). Participants performed a cycling test with incremental workload until volitional exhaustion. Serial high-sensitivity cTn (hs-cTn) T and I concentrations were measured (baseline, after 30-minute warm-up, 0/30/60/120/180 minutes post-exercise). RESULTS: 58 participants (61 [58-69] years) completed the exercise test (76±14 minutes) with a peak heart rate of 97.7 [94.8-101.8]% of their estimated maximum. Exercise duration and workload did not differ across groups. Hs-cTnT and hs-cTnI concentrations significantly increased (1.55 [1.33-2.14] fold and 2.76 [1.89-3.86] fold, respectively) over time, but patterns of cTn changes and the incidence of concentrations >99 th percentile did not differ across groups. CONCLUSIONS: Serial sampling of hs-cTnT and hs-cTnI concentrations during and following an exhaustive endurance exercise test did not reveal differences in exercise-induced cTn release between athletes with versus without coronary atherosclerosis. These findings suggest that a high CACS or a >50% stenosis in any coronary artery does not aggravate exercise-induced cTn release in middle aged and older athletes.