Chronic inflammation and impaired coronary vasoreactivity in patients with coronary risk factors.

Background— The goal of this study was to examine a possible association between systemic microinflammation, as reflected by C-reactive protein (CRP) serum levels, and coronary vasomotion in patients with coronary risk factors but with angiographically normal coronary arteries. Methods and Results— Coronary vasomotor function was studied in response to cold pressor testing (CPT) in 71 patients with normal angiograms. In all patients, CPT-induced changes in epicardial luminal area (LA; mm2) were assessed with quantitative angiography. Within 20 days, myocardial blood flow (MBF) responses to CPT were measured (mL · g−1 · min−1) noninvasively with 13N-ammonia and PET imaging. The CPT-induced mean changes in LA and in MBF in patients with elevated CRP (≥0.5 mg/dL) were significantly impaired compared with patients presenting with CRP levels within normal range (<0.5 mg/dL) (ΔLA, −1.09±0.86 versus 0.45±0.63 mm2; ΔMBF, 0.06±0.18 versus 0.44±0.31 mL · g−1 · min−1; P<0.0001, respectively). Coronary LA changes and...