Exercise‐Induced Cardiac Troponin I Elevation Is Associated With Regional Alterations in Left Ventricular Strain in High‐Troponin Responders

Abstract

Background The implications of exercise‐induced cardiac troponin elevation in healthy individuals are unclear. This study aimed to determine if individuals with a high exercise‐induced cardiac troponin I (cTnI) response have alterations in myocardial function following high‐intensity endurance exercise compared with normal‐cTnI responders. Methods and Results Study individuals were recruited from previous participants in a 91‐km mountain bike cycling race (the North Sea Race) and were classified as high‐ (n=34) or normal‐cTnI responders (n=25) based on maximal cTnI values after the recruitment race. The present study exposed all participants to 2 prolonged high‐intensity exercises: a combined lactate threshold and cardiopulmonary exercise test and repeated participation in the North Sea Race. Echocardiography was performed before, immediately after, and 24 hours following exercise. All study individuals (n=59) had normal coronary arteries, and were aged 51±10 years; 46 (74%) were men. There were no differences in baseline characteristics between the high‐ and normal‐cTnI responders. Maximal cTnI levels 3 hours after exercise were significantly higher in the high‐ compared with normal‐cTnI group (P<0.001–0.027). Following exercise, there were no differences in global ventricular function between the 2 groups. In contrast, high‐cTnI responders had significantly lower regional strain in the anteroseptal segments following exercise, with more profound changes after the race. Conclusions High‐cTnI responders had lower anteroseptal segmental strain shortly after exercise than normal‐cTnI responders. However, there were no permanent alterations in myocardial strain, indicating no short‐ or long‐term adverse consequences of these exercise‐induced alterations in myocardial function. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02166216.

Keywords

• exercise‐induced cardiac troponin elevation
• exercise‐induced myocardial alterations
• global ventricular function
• regional ventricular function