Global platelet hyperreactivity and elevated C-reactive protein levels predict long term mortality in STEMI patients

Data on long term - more than 1-year - prognostic value of global platelet reactivity (G-HPR) - by adenosine diphosphate (ADP) and arachidonic acid (AA) - in patients with STEMI undergoing PCI are limited. High C-reactive protein (CRP) levels have been suggested to be associated with post-PCI atherothrombotic events. Our aim was to evaluate the long-term prognostic impact of G-HPR and CRP levels in STEMI patients.

We evaluated 494 STEMI patients (366 M/128 F; age: 65.8 ± 12.4 yrs) undergoing PCI with stent implantation. At a median follow-up of 2.3 years (1.09-4.06), in 58 patients we documented cardiovascular death (11.7%). Platelet reactivity was assessed by light transmission aggregometry by 1mM AA (AA-LTA) and 10 microM ADP (ADP-LTA). By the ROC curve analysis, 17%, 52% and 12 mg/L were found to be the values of AA-LTA, ADP-LTA and CRP associated with the highest specificity and sensitivity for death. G-HPR was defined as the presence of both AA-LTA ≥ 17% and ADP-LTA ≥ 52%. At Cox regression analysis adjusted for age, sex, cardiovascular risk factors, multivessel disease, ejection fraction, renal insufficiency, G-HPR and elevated CRP levels were associated with long-term mortality [HR=1.78 (95%CI 1.04-3.03), p=0.036 and HR=2.91 (1.54-5.52, p=0.001), respectively]. The contemporary presence of G-HPR and elevated CRP levels was associated with the highest risk of death [HR=5.1 (95%CI 1.9-13.4), p=0.001].

G-HPR and CRP are independent long-term prognostic markers in STEMI patients. The contemporary presence of G-HPR and CRP identifies a subgroup of patients at significantly higher risk of cardiovascular death.