Intrinsic platelet reactivity before P2Y12 blockade contributes to residual platelet reactivity despite high-level P2Y12 blockade by prasugrel or high-dose clopidogrel. Results from PRINCIPLE-TIMI 44.

It was the objective of this study to determine whether the intrinsic platelet response to adenosine diphosphate (ADP) before thienopyridine exposure contributes to residual platelet reactivity to ADP despite high level P2Y12 blockade by prasugrel (60 mg loading dose [LD]), 10 mg daily maintenance dose [MD]) or high-dose clopidogrel (600 mg LD, 150 mg daily MD). High residual platelet function during clopidogrel therapy is associated with poor clinical outcomes. It remains unknown whether the relationship between platelet reactivity prior to treatment with clopidogrel (300 mg LD, 75 mg daily MD) and residual on-treatment platelet reactivity is maintained after more potent P2Y12 inhibition. PRINCIPLE-TIMI 44 was a randomised, double-blind, two-phase crossover study of prasugrel compared with high-dose clopidogrel in 201 patients undergoing cardiac catheterisation for planned percutaneous coronary intervention. ADP-stimulated platelet-monocyte aggregates, platelet surface P-selectin and platelet aggregation were measured pre-treatment, during LD (6 h and 18-24 h) and MD (15 d). Correlations of pre-treatment to on-treatment values were determined by Spearman rank order. Prasugrel resulted in greater platelet inhibition than high-dose clopidogrel for each measure. However, for both drugs, pre-treatment reactivity to ADP predicted 6 h, 18-24 h and 15 day reactivity to ADP (correlations 0.24-0.62 for platelet-monocyte aggregates and P-selectin). In conclusion, a patient's intrinsic platelet response to ADP before exposure to thienopyridines contributes to residual platelet reactivity to ADP despite high level P2Y12 blockade with high-dose clopidogrel or even higher level P2Y12 blockade with prasugrel. Patients who are hyper-responsive to ADP pre-treatment are more likely to be hyper-responsive to ADP on-treatment, which may be relevant to therapeutic strategies.

Otamixaban for the treatment of patients with non-ST-elevation acute coronary syndromes (SEPIA-ACS1 TIMI 42): a randomised, double-blind, active-controlled, phase 2 trial.

BACKGROUND: Otamixaban is an intravenous direct factor Xa inhibitor. We aimed to assess its efficacy and safety in non-ST-elevation acute coronary syndromes and to identify the optimum dose range for further assessment in a phase 3 study. METHODS: In this double-blind, phase 2 trial undertaken in 196 sites in 36 countries, 3241 patients with non-ST-elevation acute coronary syndromes were randomly assigned via a central, telephone-based interactive voice response system to one of five doses of otamixaban (0.08 mg/kg bolus followed by infusions of 0.035 [n=125], 0.070 [676], 0.105 [662], 0.140 [658], or 0.175 [671] mg/kg/h) or to a control of unfractionated heparin (60 IU/kg intravenous bolus followed by an infusion of 12 IU/kg/h) plus eptifibatide (180 microg/kg intravenous bolus followed by an infusion of 1.0-2.0 microg/kg/min [n=449]). Both investigators and patients were unaware of treatment allocation. Enrolment into the lowest dose group was stopped early at the recommendation of the Data Monitoring Committee. The primary efficacy endpoint was a composite of death, myocardial infarction, urgent revascularisation, or bailout glycoprotein IIb/IIIa inhibitor use up to 7 days. The primary safety endpoint was TIMI major or minor bleeding not related to coronary-artery bypass grafting. Efficacy analyses were by intention to treat; safety analyses were in treated patients. This study is registered with ClinicalTrials.gov, number NCT00317395. FINDINGS: Rates of the primary efficacy endpoint in the five otamixaban doses were 7.2% (nine of 125) with 0.035 mg/kg/h, 4.6% (31/676) with 0.070 mg/kg/h, 3.8% (25/662) with 0.105 mg/kg/h, 3.6% (24/658) with 0.140 mg/kg/h, and 4.3% (29/671) with 0.175 mg/kg/h (p=0.34 for trend). In the control group, the rate was 6.2% (28/449), yielding relative risks for the five otamixaban doses of 1.16 (95% CI 0.56-2.38), 0.74 (0.45-1.21), 0.61 (0.36-1.02), 0.58 (0.34-1.00), and 0.69 (0.42-1.15), respectively. Rates of the primary safety endpoint in the five otamixaban doses were 1.6% (two of 122), 1.6% (11/669), 3.1% (20/651), 3.4% (22/651), and 5.4% (36/664), respectively (p=0.0001 for trend); the rate in the control group was 2.7% (12/448). INTERPRETATION: In patients with non-ST-elevation acute coronary syndromes, otamixaban infusions of 0.100-0.140 mg/kg/h might reduce ischaemic events and have a safety profile similar to unfractionated heparin plus eptifibatide. Further testing in a phase 3 trial is warranted. FUNDING: Sanofi-Aventis.

Pharmacodynamic assessment of platelet inhibition by prasugrel vs. clopidogrel in the TRITON-TIMI 38 trial.

AIMS: To examine the extent of platelet inhibition by prasugrel vs. clopidogrel in a TRITON-TIMI 38 substudy. METHODS AND RESULTS: TRITON-TIMI 38 randomized acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI) to prasugrel or standard dose clopidogrel. Selected sites prospectively enrolled TRITON-TIMI 38 patients to evaluate adenosine diphosphate (ADP)-attenuated phosphorylation of platelet vasodilator-stimulated phosphoprotein (VASP) (n = 125 patients) and, in a subset (n = 31 patients), ADP-stimulated platelet aggregation. VASP platelet reactivity index (PRI) was lower in prasugrel-treated patients than in clopidogrel-treated patients at 1-2 h post-PCI (>or=1 h after loading dose) (P < 0.001) and at 30 days (P < 0.001). Maximal platelet aggregation to 20 microM ADP was lower in prasugrel-treated patients than in clopidogrel-treated patients at 1-2 h (P = 0.004) and 30 days (P = 0.03). Results were similar with 5 microM ADP. Thienopyridine hyporesponsiveness, prespecified as VASP PRI >50%, was more frequent in clopidogrel-treated patients than in prasugrel-treated patients at 1-2 h (P < 0.001) and 30 days (P = 0.03). CONCLUSIONS: The TRITON-TIMI 38 platelet substudy shows that prasugrel results in greater inhibition of ADP-mediated platelet function in ACS patients than clopidogrel, supporting the hypothesis that greater platelet inhibition leads to a lower incidence of ischaemic events and more bleeding both early and late following PCI.

Prasugrel compared with clopidogrel in patients undergoing percutaneous coronary intervention for ST-elevation myocardial infarction (TRITON-TIMI 38): double-blind, randomised controlled trial.

BACKGROUND: Mechanical reperfusion with stenting for ST-elevation myocardial infarction (STEMI) is supported by dual antiplatelet treatment with aspirin and clopidogrel. Prasugrel, a potent and rapid-acting thienopyridine, is a potential alternative to clopidogrel. We aimed to assess prasugrel versus clopidogrel in patients undergoing percutaneous coronary intervention (PCI) for STEMI. METHODS: We undertook a double-blind, randomised controlled trial in 707 sites in 30 countries. 3534 participants presenting with STEMI were randomly assigned by interactive voice response system either prasugrel (60 mg loading, 10 mg maintenance [n=1769]) or clopidogrel (300 mg loading, 75 mg maintenance [n=1765]) and were unaware of the allocation. The primary endpoint was cardiovascular death, non-fatal myocardial infarction, or non-fatal stroke. Efficacy analyses were by intention to treat. Follow-up was to 15 months, with secondary analyses at 30 days. This trial is registered with ClinicalTrials.gov, number NCT00097591. FINDINGS: At 30 days, 115 (6.5%) individuals assigned prasugrel had met the primary endpoint compared with 166 (9.5%) allocated clopidogrel (hazard ratio 0.68 [95% CI 0.54-0.87]; p=0.0017). This effect continued to 15 months (174 [10.0%] vs 216 [12.4%]; 0.79 [0.65-0.97]; p=0.0221). The key secondary endpoint of cardiovascular death, myocardial infarction, or urgent target vessel revascularisation was also significantly reduced with prasugrel at 30 days (0.75 [0.59-0.96]; p=0.0205) and 15 months (0.79 [0.65-0.97]; p=0.0250), as was stent thrombosis. Treatments did not differ with respect to thrombolysis in myocardial infarction (TIMI) major bleeding unrelated to coronary-artery bypass graft (CABG) surgery at 30 days (p=0.3359) and 15 months (p=0.6451). TIMI life-threatening bleeding and TIMI major or minor bleeding were also similar with the two treatments, and only TIMI major bleeding after CABG surgery was significantly increased with prasugrel (p=0.0033). INTERPRETATION: In patients with STEMI undergoing PCI, prasugrel is more effective than clopidogrel for prevention of ischaemic events, without an apparent excess in bleeding.

Myeloid-related protein 8/14 and the risk of cardiovascular death or myocardial infarction after an acute coronary syndrome in the Pravastatin or Atorvastatin Evaluation and Infection Therapy: Thrombolysis in Myocardial Infarction (PROVE IT-TIMI 22) trial.

BACKGROUND: Using a transcriptional profiling approach, we recently identified myeloid-related protein 8/14 (MRP-8/14) to be expressed by platelets during acute myocardial infarction (MI). Elevated concentrations of MRP-8/14 are associated with a higher risk for future cardiovascular events in apparently healthy individuals but have not been assessed with respect to prognosis in patients with acute coronary syndrome. METHODS: We performed a nested case-control study (n = 237 case-control pairs) among patients enrolled in the Pravastatin or Atorvastatin Evaluation and Infection Therapy: Thrombolysis in Myocardial Infarction 22 (PROVE IT-TIMI 22) trial (mean follow-up 24 months) to investigate the risk of cardiovascular death or MI associated with MRP-8/14 measured at 30 days after an acute coronary syndrome. RESULTS: Patients with cardiovascular death or MI after 30 days (cases) had higher median [25th, 75th percentile] MRP-8/14 levels than patients who remained free of recurrent events (5.6 [2.8, 13.5] mg/L vs 4.0 [1.9, 10.1] mg/L, P = .020). The risk of a recurrent cardiovascular event increased with each increasing quartile of MRP-8/14 (P-trend = 0.007) such that patients with the highest levels had a 2.0-fold increased odds (95% CI 1.1-3.6, P = .029) of a recurrent event after adjusting for standard risk indicators, randomized treatment, and C-reactive protein. Patients with elevated levels of MRP-8/14 and high-sensitivity C-reactive protein showed significantly increased risk of cardiovascular death or MI compared with patients with the lowest levels of both markers (adjusted odds ratio 2.1, 95% CI 1.2-3.8). CONCLUSIONS: Myeloid-related protein 8/14 may be a useful biomarker of platelet and inflammatory disease activity in atherothrombosis and may serve as a novel target for therapeutic intervention.

Benefits and risks of clopidogrel pretreatment before coronary artery bypass grafting in patients with ST-elevation myocardial infarction treated with fibrinolytics in CLARITY-TIMI 28.

The Clopidogrel as Adjunctive Reperfusion Therapy-Thrombolysis in Myocardial Infarction 28 (CLARITY-TIMI 28) trial was a randomized, double-blind, placebo-controlled study of clopidogrel in 3,491 patients receiving fibrinolytic therapy for ST-segment elevation myocardial infarction. Patients were randomized to clopidogrel or placebo begun at the time of fibrinolysis. This analysis reports the outcomes among the 136 patients in the trial population who underwent coronary artery bypass grafting (CABG) during the index hospitalization. There was no difference in the rates of TIMI major or minor bleeding between the clopidogrel and placebo groups from randomization to the end of follow-up (13.6% vs. 14.3%, P = 1.0) or from the time of CABG to the end of follow-up (9.1% vs. 11.4%, P = 0.78). When any day for study medication discontinuation < or = 5 days prior to CABG was chosen as a cut point to evaluate bleeding risk for clopidogrel vs. placebo, there was no excess bleeding in the clopidogrel group. Among patients undergoing CABG, there was a trend toward reduction in the risk of cardiovascular death, recurrent MI, or recurrent ischemia requiring urgent revascularization at 30 days for those taking clopidogrel (OR 0.66, 95% CI 0.27-1.5; P = 0.37), consistent with the benefit seen in the overall trial population (OR 0.80, CI 0.65-0.97; P = 0.03). In conclusion, early clopidogrel treatment among CLARITY-TIMI 28 patients undergoing CABG was not associated with an increase in the rate of peri-operative bleeding and showed a trend toward reduction in 30-day ischemic events.

Evaluation of prasugrel compared with clopidogrel in patients with acute coronary syndromes: design and rationale for the TRial to assess Improvement in Therapeutic Outcomes by optimizing platelet InhibitioN with prasugrel Thrombolysis In Myocardial Infarction 38 (TRITON-TIMI 38).

BACKGROUND: Dual antiplatelet therapy with aspirin and clopidogrel is standard for prevention of thrombotic complications of percutaneous coronary intervention (PCI). Prasugrel is a thienopyridine that is more potent, more rapid in onset, and more consistent in inhibition of platelets than clopidogrel. TRITON-TIMI 38 is designed to compare prasugrel with clopidogrel in moderate to high-risk patients with acute coronary syndrome (ACS). STUDY DESIGN: TRITON-TIMI 38 is a phase 3, randomized, double-blind, parallel-group, multinational, clinical trial. Approximately 13,000 patients with moderate to high-risk ACS undergoing PCI (9500 unstable angina/non-ST-segment elevation myocardial infarction [MI], 3500 ST-segment elevation MI) will be randomized to prasugrel 60 mg loading dose followed by 10 mg daily or clopidogrel 300 mg loading dose followed by 75 mg daily for up to 15 months. The primary end point is the time of the first event of cardiovascular death, MI, or stroke. Analyses will be performed first in the unstable angina/non-ST-segment elevation MI cohort and, conditionally, on the whole ACS population. Major safety end points include TIMI major and minor bleeding unrelated to coronary artery bypass graft surgery. CONCLUSIONS: TRITON-TIMI 38 is a phase 3 comparison of prasugrel versus clopidogrel in patients with moderate to high-risk ACS undergoing PCI. In addition, it is the first large-scale clinical events trial to assess whether a thienopyridine regimen that achieves a higher level of inhibition of platelet aggregation than the standard therapy results in an improvement in clinical outcomes.

Early initiation of eptifibatide in the emergency department before primary percutaneous coronary intervention for ST-segment elevation myocardial infarction: results of the Time to Integrilin Therapy in Acute Myocardial Infarction (TITAN)-TIMI 34 trial.

BACKGROUND: Early restoration of epicardial flow before primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) has been associated with improved clinical outcomes. METHODS: We hypothesized that early administration of the glycoprotein IIb/IIIa inhibitor eptifibatide in the emergency department (ED) would yield superior epicardial flow and myocardial perfusion before primary PCI compared with initiating eptifibatide after diagnostic angiography in the cardiac catheterization laboratory (CCL). Three hundred forty-three patients with STEMI were randomized to either early ED eptifibatide (n = 180) or CCL eptifibatide (n = 163). RESULTS: The primary end point (pre-PCI corrected TIMI frame count) was significantly lower (faster flow) with early eptifibatide (77.5 +/- 32.2 vs 84.3 +/- 30.7, P = .049). The incidence of normal pre-PCI TIMI myocardial perfusion was increased among patients treated in the ED versus CCL (24% vs 14%, P = .026). There was no excess of TIMI major or minor bleeding among patients treated in the ED versus CCL (6.9% [12/174] vs 7.8% [11/142], P = NS). CONCLUSION: A strategy of early initiation of eptifibatide in the ED before primary PCI for STEMI yields superior pre-PCI TIMI frame counts, reflecting epicardial flow, and superior TIMI myocardial perfusion compared with a strategy of initiating eptifibatide in the CCL without an increase in bleeding risk.

A randomized trial to evaluate the relative protection against post-percutaneous coronary intervention microvascular dysfunction, ischemia, and inflammation among antiplatelet and antithrombotic agents: the PROTECT-TIMI-30 trial.

OBJECTIVES: The goal of this study was to evaluate glycoprotein IIb/IIIa inhibition with eptifibatide when administered with indirect thrombin inhibition as compared with monotherapy with direct thrombin inhibition with bivalirudin among patients with non-ST-segment elevation acute coronary syndromes (ACS). BACKGROUND: The optimal combination of antiplatelet and antithrombin regimens that maximizes efficacy and minimizes bleeding among patients with non-ST-segment elevation ACS undergoing percutaneous coronary intervention (PCI) is unclear. METHODS: A total of 857 patients with non-ST-segment elevation ACS were assigned randomly to eptifibatide + reduced dose unfractionated heparin (n = 298), eptifibatide + reduced-dose enoxaparin (n = 275), or bivalirudin monotherapy (n = 284). RESULTS: Among angiographically evaluable patients (n = 754), the primary end point of post-PCI coronary flow reserve was significantly greater with bivalirudin (1.43 vs. 1.33 for pooled eptifibatide arms, p = 0.036). Thrombolysis In Myocardial Infarction (TIMI) myocardial perfusion grade more often was normal with eptifibatide treatment compared with bivalirudin (57.9% vs. 50.9%, p = 0.048). The duration of ischemia on continuous Holter monitoring after PCI was significantly longer among patients treated with bivalirudin (169 vs. 36 min, p = 0.013). There was no excess of TIMI major bleeding among patients treated with eptifibatide compared with bivalirudin (0.7%, n = 4 vs. 0%, p = NS), but TIMI minor bleeding was increased (2.5% vs. 0.4%, p = 0.027) as was transfusion (4.4% to 0.4%, p < 0.001). CONCLUSIONS: Among moderate- to high-risk patients with ACS undergoing PCI, coronary flow reserve was greater with bivalirudin than eptifibatide. Eptifibatide improved myocardial perfusion and reduced the duration of post-PCI ischemia but was associated with higher minor bleeding and transfusion rates. Ischemic events and biomarkers for myonecrosis, inflammation, and thrombin generation did not differ between agents.

Relationship between uncontrolled risk factors and C-reactive protein levels in patients receiving standard or intensive statin therapy for acute coronary syndromes in the PROVE IT-TIMI 22 trial.

OBJECTIVES: This study sought to evaluate what set of factors correlate with higher or lower C-reactive protein (CRP) levels in patients receiving standard and intensive statin therapy. BACKGROUND: C-reactive protein levels in blood are becoming recognized as a potential means of monitoring cardiovascular risk. Although statin therapy is known to reduce CRP levels, many patients have a high CRP level despite statin therapy. METHODS: This study was a cross-sectional study of 2,885 patients from the Pravastatin or Atorvastatin Evaluation and Infection Therapy-Thrombolysis In Myocardial Infarction 22 (PROVE IT-TIMI 22) trial, which assessed the relationship between uncontrolled cardiovascular risk factors and CRP level at four months after enrollment. RESULTS: In a multivariate model, several risk factors were weakly but independently associated with higher CRP levels: age, gender (with or without hormone replacement therapy), body mass index >25 kg/m2, smoking, low-density lipoprotein > or =70 mg/dl, glucose >110 mg/dl, high-density lipoprotein <50 mg/dl, triglycerides >150 mg/dl, and the intensity of statin therapy. A direct relationship between the number of uncontrolled risk factors present and CRP levels (p < 0.0001) was observed for both statin regimens. Despite the presence of each uncontrolled risk factor, prior randomization to intensive statin therapy was associated with a lower CRP level (p < 0.0001). Across all strata, defined by the number of uncontrolled risk factors present, CRP levels were lower among those receiving intensive statin therapy. CONCLUSIONS: The use of intensive statin therapy lead to a lower CRP level independent of the presence of single or multiple cardiovascular risk factors. Even among patients receiving intensive statin therapy, a lower CRP level was observed in patients with the fewest coronary risk factors present, suggesting that control of multiple risk factors may be a means to further achieve lower CRP levels.

Addition of clopidogrel to aspirin and fibrinolytic therapy for myocardial infarction with ST-segment elevation.

BACKGROUND: A substantial proportion of patients receiving fibrinolytic therapy for myocardial infarction with ST-segment elevation have inadequate reperfusion or reocclusion of the infarct-related artery, leading to an increased risk of complications and death. METHODS: We enrolled 3491 patients, 18 to 75 years of age, who presented within 12 hours after the onset of an ST-elevation myocardial infarction and randomly assigned them to receive clopidogrel (300-mg loading dose, followed by 75 mg once daily) or placebo. Patients received a fibrinolytic agent, aspirin, and when appropriate, heparin (dispensed according to body weight) and were scheduled to undergo angiography 48 to 192 hours after the start of study medication. The primary efficacy end point was a composite of an occluded infarct-related artery (defined by a Thrombolysis in Myocardial Infarction flow grade of 0 or 1) on angiography or death or recurrent myocardial infarction before angiography. RESULTS: The rates of the primary efficacy end point were 21.7 percent in the placebo group and 15.0 percent in the clopidogrel group, representing an absolute reduction of 6.7 percentage points in the rate and a 36 percent reduction in the odds of the end point with clopidogrel therapy (95 percent confidence interval, 24 to 47 percent; P<0.001). By 30 days, clopidogrel therapy reduced the odds of the composite end point of death from cardiovascular causes, recurrent myocardial infarction, or recurrent ischemia leading to the need for urgent revascularization by 20 percent (from 14.1 to 11.6 percent, P=0.03). The rates of major bleeding and intracranial hemorrhage were similar in the two groups. CONCLUSIONS: In patients 75 years of age or younger who have myocardial infarction with ST-segment elevation and who receive aspirin and a standard fibrinolytic regimen, the addition of clopidogrel improves the patency rate of the infarct-related artery and reduces ischemic complications.

Combination reperfusion therapy with eptifibatide and reduced-dose tenecteplase for ST-elevation myocardial infarction: results of the integrilin and tenecteplase in acute myocardial infarction (INTEGRITI) Phase II Angiographic Trial.

OBJECTIVES: The goal of this study was to evaluate combinations of eptifibatide with reduced-dose tenecteplase (TNK) in ST-elevation myocardial infarction (STEMI). BACKGROUND: Glycoprotein IIb/IIIa inhibitors enhance thrombolysis. The role of combination therapy in clinical practice remains to be established. METHODS: Patients (n = 438) with STEMI <6 h were enrolled. In dose-finding, 189 patients were randomized to different combinations of double-bolus eptifibatide and reduced-dose TNK. In dose-confirmation, 249 patients were randomized 1:1 to eptifibatide 180 microg/kg bolus, 2 microg/kg/min infusion, and 180 microg/kg bolus 10 min later (180/2/180) plus half-dose TNK (0.27 mg/kg) or standard-dose (0.53 mg/kg) TNK monotherapy. All patients received aspirin and unfractionated heparin (60 U/kg bolus; infusion 7 U/kg/h [combination], 12 U/kg/h [monotherapy]). The primary end point was Thrombolysis In Myocardial Infarction (TIMI) grade 3 epicardial flow at 60 min. RESULTS: In dose-finding, TIMI grade 3 flow rates were similar across groups (64% to 68%). Arterial patency was highest for eptifibatide 180/2/180 plus half-dose TNK (96%, p = 0.02 vs. eptifibatide 180/2/90 plus half-dose TNK). In dose-confirmation, this combination, compared with TNK monotherapy, tended to achieve more TIMI 3 flow (59% vs. 49%, p = 0.15), arterial patency (85% vs. 77%, p = 0.17), and ST-segment resolution (median 71% vs. 61%, p = 0.08) but was associated with more major hemorrhage (7.6% vs. 2.5%, p = 0.14) and transfusions (13.4% vs. 4.2%, p = 0.02). Intracranial hemorrhage occurred in 1.0%, 0.6%, and 1.7% of patients treated with any combination, eptifibatide 180/2/180 and half-dose TNK, and TNK monotherapy, respectively. CONCLUSIONS: Double-bolus eptifibatide (180/2/180) plus half-dose TNK tended to improve angiographic flow and ST-segment resolution compared with TNK monotherapy but was associated with more transfusions and non-cerebral bleeding. Further study is needed before this combination can be recommended for general use.

Association between plasma levels of monocyte chemoattractant protein-1 and long-term clinical outcomes in patients with acute coronary syndromes.

BACKGROUND: Monocyte chemoattractant protein-1 (MCP-1) is a chemokine responsible for the recruitment of monocytes to sites of inflammation. MCP-1 appears to play a critical role at multiple stages in atherosclerosis, including the initiation of the fatty streak, promotion of plaque instability, and remodeling after myocardial infarction. METHODS AND RESULTS: MCP-1 was measured from frozen plasma specimens in 279 healthy volunteers and 2270 patients with acute coronary syndromes enrolled in the Oral Glycoprotein IIb/IIIa Inhibition with Orbofiban in Patients with Unstable Coronary Syndromes (OPUS-TIMI) 16 trial. Median [25th, 75th percentiles] MCP-1 levels were 157 [124, 196] pg/mL in healthy volunteers and 178 [128, 238] pg/mL in the OPUS-TIMI 16 population (P<0.001). In OPUS-TIMI 16, baseline MCP-1 levels were associated with older age, female sex, hypertension, diabetes, prior coronary disease, and renal insufficiency (P<0.01 for each) but not with smoking status, body mass index, ejection fraction, troponin I or C-reactive protein. After adjustment for differences in baseline characteristics, ECG changes, troponin I, and C-reactive protein, an MCP-1 level >75th percentile (corresponding to the 90th percentile in the healthy volunteers) was associated with an increased risk of death or myocardial infarction through 10 months of follow-up (adjusted hazard ratio, 1.53; 95% CI, 1.09 to 2.14; P=0.01). CONCLUSIONS: In a large cohort of patients with acute coronary syndromes, an elevated baseline level of MCP-1 was associated both with traditional risk factors for atherosclerosis as well as an increased risk for death or myocardial infarction, independent of baseline variables. Because it appears to play a crucial role at multiple stages of atherosclerosis, MCP-1 is attractive as a surrogate biomarker and merits further study as a potential therapeutic target.

Relationship between baseline white blood cell count and degree of coronary artery disease and mortality in patients with acute coronary syndromes: a TACTICS-TIMI 18 (Treat Angina with Aggrastat and determine Cost of Therapy with an Invasive or Conservative Strategy- Thrombolysis in Myocardial Infarction 18 trial)substudy.

OBJECTIVES: This study was designed to determine the relationship between baseline white blood cell (WBC) count and angiographic and clinical outcomes in patients with unstable angina (UA)/non-ST-segment elevation myocardial infarction (NSTEMI) and to see if WBC count was a significant predictor of outcomes independent of other biomarkers. BACKGROUND: Inflammation has been shown to play a role in atherosclerosis and acute coronary syndromes. METHODS: We evaluated the relationship between baseline WBC count, other baseline variables and biomarkers, angiographic findings, and clinical outcomes in 2,208 patients in the Treat angina with Aggrastat and determine Cost of Therapy with an Invasive or Conservative Strategy-Thrombolysis In Myocardial Infarction 18 (TACTICS-TIMI 18) trial. RESULTS: Higher baseline WBC counts were associated with lower Thrombolysis In Myocardial Infarction (TIMI) flow grades (p = 0.0045) and TIMI myocardial perfusion grades (p = 0.03) as well as a greater extent of coronary artery disease (CAD) (p < 0.0001). A higher baseline WBC count was predictive of higher six-month mortality, ranging from 1.5% to 3.6% to 5.1% for patients with low, intermediate, and high WBC counts, respectively (p = 0.0017). In a multivariable proportional hazards model, patients with a low C-reactive protein (CRP) but an elevated WBC remained at significantly higher risk of death at six months (hazard ratio [HR] 4.3, p = 0.049), and patients with a high CRP were at even higher risk (HR 8.6, p = 0.004). conclusions: In patients with UA/NSTEMI, elevations in a simple, widely available blood test, the WBC count, were associated with impaired epicardial and myocardial perfusion, more extensive CAD, and higher six-month mortality. After adjustment for traditional risk factors and other biomarkers, assessment of two inflammatory markers, WBC count and CRP, can be used to stratify patients across an eightfold gradation of six-month mortality risk.