D-Dimer Levels Predict Myocardial Injury in ST-Segment Elevation Myocardial Infarction: A Cardiac Magnetic Resonance Imaging Study.

Elevated D-dimer levels on admission predict prognosis in patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI), but the association of D-dimer levels with structural markers of myocardial injury in these patients is unknown.We performed cardiac magnetic resonance (CMR) imaging in 208 patients treated with primary PCI for STEMI. CMR was performed a median of 3 days after the index procedure. Of the 208 patients studied, 75 patients had D-dimer levels above the normal range on admission (>0.5 μg/mL; high D-dimer group) while 133 had normal levels (≤0.5 μg/mL; low D-dimer group). The primary outcome was myocardial infarct size assessed by CMR. Secondary outcomes included area at risk (AAR), microvascular obstruction (MVO) area, and myocardial salvage index (MSI).In CMR analysis, myocardial infarct size was larger in the high D-dimer group than in the low D-dimer group (22.3% [16.2-30.5] versus 18.8% [10.7-26.7]; p = 0.02). Compared to the low D-dimer group, the high D-dimer group also had a larger AAR (38.1% [31.7-46.9] versus 35.8% [24.2-45.3]; p = 0.04) and a smaller MSI (37.7 [28.2-46.9] versus 47.1 [33.2-57.0]; p = 0.01). In multivariate analysis, high D-dimer levels were significantly associated with larger myocardial infarct (OR 2.59; 95% CI 1.37-4.87; p<0.01) and lower MSI (OR 2.62; 95% CI 1.44-4.78; p<0.01).In STEMI patients undergoing primary PCI, high D-dimer levels on admission were associated with a larger myocardial infarct size, a greater extent of AAR, and lower MSI, as assessed by CMR data. Elevated initial D-dimer level may be a marker of advanced myocardial injury in patients treated with primary PCI for STEMI

Baseline Characteristics of Study Participants.

<p>Baseline Characteristics of Study Participants.</p

Scheme of Group Distribution.

<p>AMI-CMR = acute myocardial infarction–cine magnetic resonance imaging; STEMI = ST-segment elevation myocardial infarction; NSTEMI = non ST-segment elevation myocardial infarction; PCI = percutaneous coronary intervention; CMR = cardiac magnetic resonance imaging.</p

Example Images From a Study of Reperfused Anterior ST-segment Elevation Myocardial Infarction.

<p>Representative cardiac magnetic resonance images of a reperfused anterior ST-segment elevation myocardial infarction: (A) high D-dimer level with a short-axis slice of a T2-weighted image, (B) high D-dimer level with a late-gadolinium enhancement image, (C) low D-dimer level with a short-axis slice of a T2-weighted image, (D) low D-dimer level with a late-gadolinium enhancement image. In these cases, D-dimer levels, area at risk, and infarct size were 1.43μg/mL versus 0.26μg/mL, 72.2% versus 55.6% and 38.6% versus 17.9%, respectively, yielding a myocardial salvage index of 46.5 versus 67.8.</p

Multivariable logistic regression analyses for Predictors of Advanced Myocardial Injury.

<p>Multivariable logistic regression analyses for Predictors of Advanced Myocardial Injury.</p

Cardiac Magnetic Resonance Findings According to D-dimer Level.

<p>Boxplots shows cardiac magnetic resonance data according to D-dimer level and (A) myocardial infarct size, (B) area at risk, (C) myocardial salvage index, and (D) LVEF.</p

Linear regression analyses for Relationship Between Myocardial Injury, Level of D-dimer, and Age.

<p>(A) Relationship between D-dimer level and infarct size. (B) Relationship between D-dimer level and myocardial salvage index. (C) Relationship between age and infarct size. (D) Relationship between age and myocardial salvage index.</p