Long-Term Prognostic Significance of High-Sensitive Troponin I Increase during Hospital Stay in Patients with Acute Myocardial Infarction and Non-Obstructive Coronary Arteries.

Background and Objectives: A topic already widely investigated is the negative prognostic value regarding the extent of high sensitive troponin I (hs-TnI) increases among patients with myocardial infarction (MI) and obstructive coronary atherosclerosis compared to a group of patients with MI and non-obstructive coronary atherosclerosis (MINOCA). Thus, the aim of this study was to evaluate the prognostic value concerning the extent of hs-TnI increase on clinical outcomes among patients with a MINOCA working diagnosis. Materials and Methods: We selected 337 consecutive patients admitted to hospital with a working diagnosis of MINOCA. The patients were divided in three groups according to the extent of hs-TnI increase during hospitalization (increase ≤5-times above the limit of the upper norm, >5 and ≤20-times, and >20-times). The study endpoints included all-cause mortality and major adverse cardiac and cerebrovascular events (MACCE; cerebral stroke and transient ischemic attacks, MI, coronary artery revascularization, either percutaneous coronary intervention or coronary artery bypass grafting and all-cause mortality). Results: During the mean follow-up period of 516.1 ± 239.8 days, using Kaplan-Meier survival curve analysis, significantly higher mortality rates were demonstrated among patients from the group with the greatest hs-TnI increase compared to the remaining groups (p = 0.01) and borderline values for MACCE (p = 0.053). Multivariable cox regression analysis did not confirm hs-TnI among factors related to increased MACCE or all-cause mortality rates. Conclusion: While a relationship between clinical outcomes and the extent of the hs-TnI increase among patients with a MINOCA working diagnosis remains, it does not seem to be not as strong as it is in patients with obstructive coronary atherosclerosis.