Context Acute ST-segment elevation myocardial infarction (STEMI) is a leading cause of morbidity and mortality. In experimental models of MI, erythropoietin reduces infarct size and improves left ventricular (LV) function. Objective To evaluate the safety and efficacy of a single intravenous bolus of epoetin alfa in patients with STEMI. Design, Setting, and Patients Prospective, randomized, double-blind, placebo-controlled trial with a dose-escalation safety phase and a single-dose (60,000 units of epoetin alfa) efficacy phase involving 222 patients with STEMI who underwent successful percutaneous coronary intervention (PCI) as a primary or rescue reperfusion strategy. Intervention Participants were randomly assigned to treatment with intravenous epoetin alfa or matching saline placebo administered within 4 hours of reperfusion. Main Outcome Measure Infarct size, expressed as a percentage of LV mass, assessed by cardiac magnetic resonance (CMR) imaging 2–6 days after study medication administration. Results In the efficacy cohort (n=138), infarct size did not differ between groups at either 2–6 days (15.8±10.3 vs. 15.0±10.0, P=.666) or 12±2 weeks (10.6±8.6 vs. 10.4±7.6, P=.886). Left ventricular ejection fraction also did not differ between groups at either the early (48.2±9.1 vs. 48.9±8.7, P=.671) or late (52.5±9.3 vs. 52.0±8.8, P=.760) timepoints. In pre-specified analyses of patients aged ≥70 years (n=21), mean infarct size within the first week was larger in the epoetin alfa arm than in the placebo group (19.9±9.9 vs.11.7±7.2, P=.026). Patients who received epoetin alfa had a higher incidence of the composite endpoint of death, myocardial infarction, stroke, or stent thrombosis (4.0% vs. 0.0%, P=.042), and a higher incidence of serious adverse events (20.0% vs. 10.3%, P=.052). Conclusions In STEMI patients successfully reperfused with primary or rescue PCI, a single intravenous bolus of epoetin alfa did not reduce infarct size and was associated with higher rates of adverse cardiovascular events. Furthermore, it may be associated with increased infarct size in older patients. Trial Registration clinicaltrials.gov identifier NCT00378352.

Deuterium exchange was monitored by electrospray ionization mass spectrometry (ESI-MS) to study the slowly exchanging (hydrogen bonded) peptide hydrogens of several a-helical peptides and &sheet proteins. Polypeptides were synthetically engineered to have mainly disordered, a-helical, or 0-sheet structure. For 3 isomeric 31-residue a-helical peptides, the number of slowly exchanging hydrogens as measured by ESI-MS in 50% CF3CD20D (pD 9.5) provided estimates of their a-helicities (26V0, 40%, 94%) that agreed well with the values (17%, 34%, 98%) measured by circular dichroic spectroscopy in the same nondeuterated solvent. For 3 betabellins containing a pair of 0-sheets and a related disordered peptide, their order of structural stability (12D > 12s > 14D > 14s) shown by their deuterium exchange rates in 10% CD30D/0.5% CD3C02D (pD 3.8) as measured by ESI-MS was the same as their order of structural stability to unfolding with increasing temperature or guanidinium chloride concentration as measured by circular dichroic spectroscopy in water. Compared to monitoring deuterium exchange by proton NMR spectrometry, monitoring deuterium exchange by ESI-MS requires much less sample (1-50 pg), much shorter analysis time (10-90 min), and no chemical quenching of the exchange reaction.

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Background Acute myocardial infarction (MI) remains a leading cause of death despite advances in pharmacologic and percutaneous therapies. Animal models of ischemia/reperfusion have demonstrated that single-dose erythropoietin (EPO) may reduce infarct size, decrease apoptosis, and increase neovascularization, possibly through mobilization of endothelial progenitor cells (EPCs). Study Design REVEAL is a randomized, double-blind, placebo-controlled, multicenter trial evaluating the effects of epoetin alfa on infarct size and left ventricular (LV) remodeling in patients with large MIs. The trial comprises a dose-escalation safety phase and a single-dose efficacy phase using the highest acceptable epoetin alfa dose up to 60,000 units. Up to 250 STEMI patients undergoing primary or rescue percutaneous coronary intervention (PCI) will be randomized to intravenous epoetin alfa or placebo within 4 hours of successful reperfusion. The primary study endpoint is infarct size expressed as a percentage of LV mass, as measured by cardiac magnetic resonance imaging 2–6 days post study medication administration. Secondary endpoints will assess changes in EPC numbers and changes in indices of ventricular remodeling. Conclusion The REVEAL trial will evaluate the safety and efficacy of the highest tolerated single dose of epoetin alfa in patients who have undergone successful rescue or primary PCI for acute STEMI.