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Background: Diabetes mellitus is a major risk factor for adverse outcomes after acute coronary syndromes (ACS). Because this disease may be associated with increased platelet aggregation, we investigated whether diabetic patients with ACS derive particular benefit from platelet glycoprotein (GP) IIb/IIIa receptor inhibition., Methods and Results: We performed a meta-analysis of the diabetic populations enrolled in the 6 large-scale platelet GP IIb/IIIa inhibitor ACS trials: PRISM, PRISM-PLUS, PARAGON A, PARAGON B, PURSUIT, and GUSTO IV. Among 6458 diabetic patients, platelet GP IIb/IIIa inhibition was associated with a significant mortality reduction at 30 days, from 6.2% to 4.6% (OR 0.74; 95% CI 0.59 to 0.92; P=0.007). Conversely, 23 072 nondiabetic patients had no survival benefit (3.0% versus 3.0%). The interaction between platelet GP IIb/IIIa inhibition and diabetic status was statistically significant (P=0.036). Among 1279 diabetic patients undergoing percutaneous coronary intervention (PCI) during index hospitalization, the use of these agents was associated with a mortality reduction at 30 days from 4.0% to 1.2% (OR 0.30; 95% CI 0.14 to 0.69; P=0.002)., Conclusions: This meta-analysis, including the entire large-scale trial experience of intravenous platelet GP IIb/IIIa inhibitors for the medical management of non-ST-segment-elevation ACS, shows that these agents may significantly reduce mortality at 30 days in diabetic patients. Although not based on a randomized assessment, the survival benefit appears to be of greater magnitude in patients undergoing PCI. Therefore, the use of platelet GP IIb/IIIa inhibitors should be strongly considered in diabetic patients with ACS.

Background- A reactivation of ischemia after the discontinuation of intravenous heparin in acute coronary syndromes has been described. The effect of glycoprotein IIb/IIIa blockade on heparin rebound is unknown. Methods and Results- Patients with acute coronary syndromes who received heparin therapy but not initial revascularization in the Platelet IIb/IIIa in Unstable angina: Receptor Suppression Using Integrilin Therapy (PURSUIT) trial were analyzed. Rates of death or myocardial (re)infarction while on heparin therapy and in 12-hour periods in the 2 days after heparin discontinuation were compared between eptifibatide and placebo. There was no difference between study groups in event rates during heparin infusion. In the 12 hours after heparin discontinuation, there was a 2.5-fold increase in all events, an 8-fold increase in death, and a 2-fold increase in myocardial infarction. However, in the 12 hours after heparin discontinuation, there was a significantly lower rate of events (1.68% versus 2.53%, P=0.03) and death (0.77% versus 0.21%, P=0.002) in the eptifibatide group compared with the placebo group. When only considering patients who were on study drug at the time of heparin discontinuation, the reduction in the combined end point was marginally significant, but the difference in the rate of death remained significant (0.68% versus 0.06%, P=0.004). In logistic regression analyses, the multivariate predictors of rebound events were the duration of heparin therapy, age, North American site, and lack of eptifibatide treatment. Conclusions- An increase in death or myocardial infarction occurs in the 12 hours after heparin discontinuation in patients with acute coronary syndromes. This rebound is attenuated by glycoprotein IIb/IIIa inhibition with eptifibatide.

Background: Established methods of risk assessment in percutaneous coronary intervention have focused on clinical and anatomical lesion characteristics. Emerging evidence indicates the substantial contribution of inflammatory processes to short-term and long-term outcomes in coronary artery disease., Methods and Results: Within a single-center registry of contemporary percutaneous coronary revascularization strategies with postprocedural creatine kinase and clinical events routinely recorded, we assessed the association of baseline C-reactive protein with death or myocardial infarction within the first 30 days. Predictive usefulness of baseline C-reactive protein within the context of established clinical and angiographic predictors of risk was also examined. Among 727 consecutive patients, elevated baseline C-reactive protein before percutaneous coronary intervention was associated with progressive increase in death or myocardial infarction at 30 days (lowest quartile, 3.9%, versus highest quartile, 14.2%; P=0.002). Among clinical and procedural characteristics, baseline C-reactive protein remained independently predictive of adverse events, with the highest quartile of C-reactive protein associated with an odds ratio for excess 30-day death or myocardial infarction of 3.68 (95% CI, 1.51 to 8.99; P=0.004). A predictive model that included baseline C-reactive protein quartiles, American College of Cardiology/American Heart Association lesion score, acute coronary syndrome presentation, and coronary stenting appears strongly predictive of 30-day death or myocardial infarction within this population (C-statistic, 0.735) and among individual patients (Brier score, 0.006)., Conclusions: Elevated baseline C-reactive protein portends heightened risk of 30-day death or myocardial infarction after coronary intervention. Coupled anatomic, clinical, and inflammatory risk stratification demonstrates strong predictive utility among patients undergoing percutaneous coronary intervention and may be useful for guiding future strategies.

Background: Patients with a recent episode of non-ST-segment elevation acute coronary syndrome before CABG have higher rates of operative morbidity and mortality than patients with stable coronary syndromes. The efficacy of administering eptifibatide to these patients undergoing in-hospital CABG is unknown., Methods and Results: The Platelet Glycoprotein IIb-IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy (PURSUIT) trial randomized 10 948 patients to receive either eptifibatide or placebo. There were 1558 study participants who underwent in-hospital CABG: 692 received placebo, and 866 received eptifibatide. The main substudy analysis end point was death or myocardial infarction (MI) rates at the 6-month follow-up. The 30-day death or MI rates were 30. 8% and 26.1% for the placebo and eptifibatide groups, respectively (P:=0.041). The benefit of eptifibatide administration persisted through 6-months of follow-up (32.7% versus 27.6% for placebo versus eptifibatide, respectively; P:=0.029). There was a greater reduction in the 6-month death or MI rate for patients who received eptifibatide within 72 hours of CABG (33.6% versus 23.8%; P:=0.002) compared with the >72-hour group (31.6% versus 32%; P:=1.0). The incidence of major bleeding was 56.6% for placebo-treated patients versus 58.2% for eptifibatide-treated patients (P:=0.7)., Conclusions: Eptifibatide administration in patients undergoing in-hospital CABG with a recent episode of a non-ST-segment elevation acute coronary syndrome results in a significant reduction in death or MI that is evident at 7 days and persists through the 6-month follow-up without a significant increase in perioperative bleeding rates.

Background: Stenting likely decreases the need for target-vessel revascularization procedures in diabetic patients compared with balloon angioplasty. However, the efficacy of stenting with platelet glycoprotein IIb/IIIa blockade has not yet been assessed in diabetics., Methods and Results: We analyzed the outcomes of 491 diabetic patients within the multicenter Evaluation of Platelet IIb/IIIa Inhibitor for Stenting Trial (EPISTENT). Diabetic patients were a prospectively defined subset: 173 were randomized to stent-placebo, 162 to stent-abciximab, and 156 to balloon angioplasty-abciximab. The main end point for this analysis was combined 6-month death, myocardial infarction (MI), or target-vessel revascularization (TVR). The composite end point occurred in 25.2% of stent-placebo, 23.4% of balloon-abciximab, and 13.0% of stent-abciximab patients (P=0.005). Abciximab therapy, irrespective of revascularization strategy (stent or balloon angioplasty), resulted in a significant reduction in the 6-month death or MI rate: 12.7% for stent-placebo, 7.8% for balloon angioplasty-abciximab, and 6.2% for the stent-abciximab group (P=0.029). The 6-month TVR rate was 16.6% for stent-placebo, 18.4% for balloon-abciximab, and 8.1% for stent-abciximab (P=0.021). Compared with stent-placebo, stent-abciximab therapy was associated with a significant increase in angiographic net gain (0.88 versus 0.55 mm; P=0.011) and a decrease in the late loss index (0.40 versus 0.60 mm; P=0.061). The 1-year mortality rate for diabetics was 4.1% for stent-placebo and 1. 2% for stent-abciximab patients (P=0.11)., Conclusions: The combination of stenting and abciximab therapy among diabetics resulted in a significant reduction in 6-month rates of death, MI, and TVR compared with stent-placebo or balloon-abciximab therapy.

High-voltage electrical trauma frequently results in extensive and scattered destruction of skeletal muscle along the current path. The damage is commonly believed to be mediated by heating. Recent experimental and theoretical evidence suggests, however, that the rhabdomyolysis and secondary myoglobin release that occur also can result from electroporation, a purely nonthermal mechanism. Based on the results of a computer simulation of a typical high-voltage electric shock, we have postulated that electroporation contributes substantially to skeletal muscle damage and could be the primary mechanism of damage in some cases of electrical injury. In this study, we determined the threshold field strength and exposure duration required to produce rhabdomyolysis by the electroporation mechanism. The change in the electrical impedance of intact skeletal muscle tissue following the application of short-duration, high-intensity electric field pulses is used as an indicator of membrane damage. Our experiments show that a decrease in impedance magnitude occurs following electric field pulses that exceed threshold values of 60 V/cm magnitude and 1-ms duration. The field strength, pulse duration, and number of pulses are factors that determine the extent of damage. The effect does not depend on excitation-contraction coupling. Electron micrographs confirm structural defects created in the membranes by the applied electric field pulses, and these represent the first clear demonstration of rhabdomyolysis in intact muscle due to electroporation. These results provide compelling evidence in support of our postulate.