Autoantibodies to cardiac troponin in acute coronary syndromes

In a recent small study, patients with autoantibodies to cardiac troponin (cTnaAb) had higher cardiac troponin I (cTnI) release during an episode of acute coronary syndrome (ACS) than patients without cTnaAb and continued to have higher long-term levels of cTnI. However, the prognostic importance of the occurrence of cTnaAb is unknown.

In 957 nonST-elevation ACS patients cTnaAb and cTnI were analyzed at randomization and after 6 months. Outcomes were assessed through 5 years.

Seven and 11% of the patients were cTnaAb positive at inclusion and 6months, respectively. The cardiac troponin I (cTnI) concentration at inclusion was independently associated with the development of cTnaAb (OR 1.53, 95% CI 1.25-1.88). The presence of cTnaAb was associated with an increased cTnI level at 6 months (OR 2.39, 95% CI 1.50-3.81). cTnaAb was not independently associated with death and AMI during follow-up (HR 0.97, 95% CI 0.61-1.54).

Development of cTnaAb after an episode of nonST-elevation ACS is associated with the acute myocardial damage, but occurs only in a minority of patients. Furthermore, the presence of cTnaAb is associated with chronically elevated cTnI concentrations. However, the occurrence of cTnaAb is not associated with an adverse long-term prognosis.