Study objective
Return-to-play (RTP) decision includes cardiac troponin I returning to baseline. Formation of antibodies to cardiac troponin I (macrocomplexes) may lead to persistent, false positively elevated cardiac troponin I and may induce unnecessary exclusion from competitive sports.
Design
Single-centre retrospective study.
Setting
Sports cardiological outpatient clinic.
Participants
We investigated 12 asymptomatic athletes who had clinically recovered from their first episode of acute myocarditis, but who showed persistently elevated cardiac troponin I levels without kinetics.
Interventions
Testing for the presence of macrocomplexes using an Abbott high-sensitivity cardiac troponin I assay with and without polyethylene glycol (PEG) precipitation to precipitate any potential macrocomplexes present in the samples.
Main outcome measures
Prevalence of a cardiac troponin I recovery rate in PEG precipitation.
Results
13 samples from 12 athletes (mean age 36.2 ± 12.3 years) were examined with a cardiac troponin I range from 35.4 ng/L to 951 ng/L. After PEG precipitation, a measurable cardiac troponin I concentration was detected in only two cases. In 12 of the 13 samples examined, the cardiac troponin I recovery rate was below 35%, which suggests the presence of macrocomplexes. Mean time from diagnosis of acute myocarditis to assessment of macrocomplexes was 6.2 ± 3.6 months.
Conclusion
Formation of macrocomplexes seems to be highly prevalent in athletes who have clinically recovered from acute myocarditis. PEG precipitation may be a feasible laboratory approach to help in the clinical decision-making of athletes to avoid unnecessary exclusion from competitive sports.