Background The pathobiology of
myocardial infarction (MI) with nonobstructive coronary arteries (
MINOCA) is often uncertain. Investigating
biomarker concentrations and their changes may offer novel pathophysiological insights. Methods and Results In this post hoc study of the PLATO (Platelet Inhibition and Patient Outcomes) trial, concentrations of hs-cTnT (high-sensitivity cardiac
troponin T),
NT-proBNP (N-terminal pro-
B-type natriuretic peptide),
hs-CRP (
high-sensitivity C-reactive protein), and
GDF-15 (
growth differentiation factor 15) were measured in patients with
MINOCA at baseline (n=554) and at 1-month follow-up (n=107). For comparisons,
biomarkers were also measured in patients with MI with obstructive (
stenosis ≥50%)
coronary artery disease (baseline: n=11 106; follow-up: n=2755]). Adjusted linear regression models were used to compare concentrations and their short- and long-term changes. The adjusted geometric mean ratios (GMRs) in patients with
MINOCA (median age, 61 years; 50.4% women) indicated lower hs-cTnT (GMR, 0.77 [95% CI, 0.68-0.88]) but higher
hs-CRP (GMR, 1.21 [95% CI, 1.08-1.37]) and
GDF-15 concentrations (GMR, 1.06 [95% CI, 1.02-1.11]) at baseline compared with patients with MI with obstructive
coronary artery disease, whereas
NT-proBNP concentrations were similar. Temporal decreases in hs-cTnT,
NT-proBNP, and
hs-CRP concentrations until 1-month follow-up were more pronounced in patients with
MINOCA. At follow-up, patients with
MINOCA had lower concentrations of hs-cTnT (GMR, 0.71 [95% CI, 0.60-0.84]),
NT-proBNP (GMR, 0.45 [95% CI, 0.36-0.56]), and
hs-CRP (GMR, 0.68 [95% CI, 0.53-0.86]). One-month
GDF-15 concentrations were similar between both groups with MI. Conclusions
Biomarker concentrations suggest greater initial inflammatory activity, similar degree of myocardial dysfunction, and less pronounced myocardial injury during the acute phase of
MINOCA compared with MI with obstructive
coronary artery disease but also faster myocardial recovery. Registration URL: http://www.clinicaltrials.gov; Unique identifier: NCT00391872.