Faculty Bibliography

Evaluation of: Schachinger V, Erbs S, Elsasser A et al.: Intracoronary bone marrow-derived progenitor cells in acute myocardial infarction. N. Engl. J. Med. 355, 1210-1221 (2006). The Reinfusion of Enriched Progenitor cells And Infarct Remodeling in Acute Myocardial Infarction (REPAIR-AMI) trial, the largest randomized, placebo-controlled trial of stem cell therapy in acute myocardial infarction, studied the efficacy of the intracoronary delivery of bone marrow mononuclear cells (BMCs) versus placebo in patients with acute ST-segment elevation myocardial infarction following successful percutaneous coronary intervention. At 4 month follow-up, patients treated with BMCs had a significant improvement in left ventricular ejection fraction compared with placebo (+5.5 vs +3.0%, absolute difference +2.5%). In addition, treatment with BMCs was associated with a statistically significant reduction in adverse clinical events at 1 year follow-up. Despite these promising findings, other studies have shown mixed results and several unresolved clinical and physiological issues remain. Key findings from ongoing basic and clinical research will define the future role of stem cell therapy for acute myocardial infarction.

Anemia is common among patients with coronary artery disease (CAD) and portends a higher risk of short- and long-term mortality, major adverse cardiac events, and bleeding complications. Blood transfusion has long been the cornerstone of therapy for anemia; however, its benefit in patients with CAD is controversial and the appropriate threshold for transfusion has been widely debated. In this review, we summarize the studies evaluating the impact of anemia in patients with CAD undergoing percutaneous coronary intervention and address several issues regarding the use of transfusion in anemic patients. In addition, we discuss alternative options for the management of anemia, such as the use of erythropoietin, aqueous oxygen, and hemoglobin-based oxygen carriers.

For patients undergoing percutaneous coronary intervention (PCI), bleeding complications are a major clinical concern. With advances in pharmacotherapy and devices over the past 2 decades, the risk of ischemic outcomes, such as myocardial infarction or death, has decreased. Bleeding complications have more recently become a clinical and research priority. Determining the incidence of and risk factors for bleeding is complicated by the multiple systems used to classify bleeding severity and report bleeding events. The origin of the data, clinical trials versus registries, also influences the incidence of reported bleeding events. Registry data suggest that risk of bleeding among patients undergoing PCI is higher in clinical practice than the incidence observed in clinical trials. Another clinical concern is the possible association between PCI-related bleeding complications and myocardial infarction, stroke, or death. Reduction in bleeding risk is a desirable goal that may potentially improve survival and increase comfort for patients undergoing PCI. Using strategies such as careful vascular access, alternative radial artery access, and modified antithrombotic regimen may reduce bleeding during PCI as well as improve patient outcomes.