ABSTRACT
BACKGROUND: To evaluate the possible independent impact of circulating total homocysteine (tHcy) levels on long-term cardiovascular mortality, in patients with either ST-segment elevation myocardial infarction (STEMI), or non-ST-segment elevation acute coronary syndromes (NSTE-ACS). METHODS: A total of 458 STEMI and 476 NSTE-ACS patients who presented consecutively, within the first 12 and 24 h of index pain respectively were studied. Each cohort was divided according to tertiles of circulating tHcy levels upon presentation. Early (30 days) and late (31 days through 5 years) cardiovascular mortality was the predefined study endpoint. RESULTS: There was no difference in the risk of 30-day cardiovascular death among the tertiles of tHcy in patients with STEMI (7.2%, 8.5% and 12.4% for the first, second and third tertiles respectively; p(trend)=0.3) or NSTE-ACS (3.1%, 3.8% and 5.7% for the first, second and third tertiles respectively; p(trend)=0.5). Patients in the upper tHcy tertile were at significantly higher unadjusted risk of late (from 31 days trough 5 years) cardiovascular death than those in the other two tertiles in STEMI (23.4%, 27.9% and 41.8% for the first, second and third tertiles respectively; p(trend) <0.001), and NSTE-ACS (24.7%, 28.1% and 45.6% for the first, second and third tertiles respectively; p(trend) <0.001) cohorts. However, after adjustment for baseline differences, there was no significant difference in the risk of late cardiovascular death among tHcy tertiles in either cohort. When circulating tHcy levels were treated as a continuous variable, they were significantly associated with late cardiovascular death (p<0.001 for both cohorts) by univariate Cox regression analysis, but not by multivariate Cox regression analysis (p=0.8, and p=1 for STEMI and NSTE-ACS cohorts, respectively). CONCLUSIONS: Based on the present data circulating tHcy levels determined upon admission do not serve as an independent predictor of long-term cardiovascular mortality in patients with either STEMI or NSTE-ACS.
Subject(s)
Coronary Disease/blood , Coronary Disease/mortality , Homocysteine/blood , Acute Disease , Biomarkers/blood , Electrocardiography , Female , Follow-Up Studies , Greece/epidemiology , Humans , Male , Middle Aged , Nephelometry and Turbidimetry , Prognosis , Retrospective Studies , Risk Factors , Survival Rate/trends , Syndrome , Time FactorsABSTRACT
BACKGROUND: Decreased responsiveness to oral antiplatelet drug therapy has been associated with an adverse outcome after coronary stenting (CS), but more studies are needed. The purpose of the present study was to prospectively evaluate this issue. METHODS: A total of 612 consecutive patients with stable or unstable coronary artery disease who underwent CS after at least 12 hours of aspirin and clopidogrel loading were studied. The study population was divided into responders and nonresponders to oral antiplatelet therapy, according to the values of preprocedural Platelet Function Analyzer-100 (Dade Behring, Marburg, Germany) collagen epinephrine closure time (CEPI-CT). In particular, responders were considered as patients with a CEPI-CT > 193 seconds and nonresponders as those with a CEPI-CT < or = 193 seconds. The 1-year incidence of the composite of cardiac death and rehospitalization for nonfatal myocardial infarction was the prespecified primary study end point. RESULTS: At 1 year, 9.1% of patients reached the primary end point. Nonresponders to oral antiplatelet therapy were at significantly higher risk for the primary end point (18.7% vs 7.6%) than responders. Nonresponsiveness to oral antiplatelet therapy was a predictor of the primary end point by both univariate (hazard ratio 2.7, 95% CI 1.6-4.5, P < .001) and multivariate (hazard ratio 2.5, 95% CI 1.6-3.8, P < .001) Cox regression analysis. CONCLUSION: Based on the present data, preprocedural responsiveness to oral antiplatelet therapy, assessed by Platelet Function Analyzer-100 CEPI-CT, is an independent predictor of long-term outcome after CS.
