Relation of C-reactive protein to extent and complexity of coronary narrowing in patients with non-ST elevation acute coronary syndromes. A prospective cohort study.

Background Inflammatory markers have been associated with adverse clinical outcome in patients with acute coronary syndromes (ACS). In addition, angiographic plaque morphology and extension of coronary artery disease has been related to worse prognosis in this group of patients. The aim of the present study was to determine if the clinical prognostic value of C-reactive protein (CRP), an inflammatory marker, can by associated with the angiographic findings in patients with non-ST elevation ACS. Methods This prospective multicenter cohort study included 1253 patients with non-ST elevation ACS. CRP, which was considered positive (+) if ≥ 3 mg/l, was measured at a median of 9 h from symptoms onset and were kept blinded until the end of the study. Coronary angiography was performed in 633 patients (50%). The presence of complex coronary lesions (CCLs) was defined as the presence of any of the following: thrombus (+), Thrombolysis In Myocardial Infarction (TIMI) flow ≤ 2, and/ or ulcerated plaque (UP). The extension of coronary disease was defined as one, two or three vessel disease. Results CRP was found to be (+) in 354 patients (60%). CCLs were present in 266 patients (46%), 166 (47%) in CRP (+) and 100 (42%) in CRP negative (-) patients, P=0.31. There was also no association between the extension of coronary disease and the CRP levels. Conclusions In this large consecutive cohort of non-ST elevation ACS patients, CRP, an inflammatory marker, does not predict either the extension or the complexity of coronary disease. Even though CRP is a strong predictor of worse clinical outcome in patients with ACS, this could not be explained by the angiographic anatomic findings.