Comparison of usefulness of C-reactive protein versus white blood cell count to predict outcome after primary percutaneous coronary intervention for ST elevation myocardial infarction.

White blood cell (WBC) count and high-sensitive C-reactive protein (hs-CRP) are both used as markers of inflammation and prognosis after an ST elevation myocardial infarction (STEMI), but it is unknown whether they have independent prognostic value. We investigated the association and independent prognostic importance of WBC and hs-CRP after STEMI. In this subanalysis of the On-TIME trial, in 490 of 507 (97%) patients, either WBC count or CRP, and in 362 (71%) patients, both WBC count and CRP, were measured on admission before primary percutaneous coronary intervention. There was no significant correlation between WBC count and CRP (R = 0.080). Higher levels of CRP were associated with a reinfarction or death within 1 year (mean hs-CRP 14.2 +/- 20.4 vs 6.1 +/- 14.2, p = 0.006), but CRP was not associated with enzymatic infarct size (lactate dehydrogenase, LDHQ48) or left ventricular ejection fraction. A higher baseline WBC count was associated with larger LDHQ48 and lower left ventricular ejection fraction but not with 1-year reinfarction or death. In conclusion, although both WBC count and CRP are markers of inflammation and predictors of outcome after STEMI, we did not find a correlation between baseline WBC count and CRP levels in patients treated with primary percutaneous coronary intervention for STEMI. The mechanisms by which WBC counts predict outcome were related to myocardial infarct size whereas CRP were not.