Impact of anemia on nonfatal coronary events after percutaneous coronary interventions

Anemia is associated with higher rates of cardiovascular events in patients with heart failure, acute myocardial infarction, and in patients undergoing coronary artery bypass graft surgery. Although studies have focused on fatal coronary events in anemic patients following percutaneous coronary intervention (PCI), data is lacking regarding nonfatal coronary events. The aim of our study was to analyze the incidence of anemia in patients who developed nonfatal events after successful PCI, and to make a comparison with event-free patients. Forty-nine consecutive patients with and 51 without nonfatal coronary events (nonfatal myocardial infarction, coronary artery bypass grafting, or repeat PCI) during the 1-year follow-up after the index PCI procedure were included in the study. Anemia was defined using World Health Organization (WHO) criteria as a hematocrit value at initial presentation < 39% for men and < 36% for women. Baseline hematocrit levels were measured before the procedure. Baseline clinical, lesion, and procedural characteristics were comparable in both groups. Anemia was present in 33.8% of men and 30.4% of women. The incidence of anemia in patients with nonfatal coronary events was 46.9% and 15.7% in the event-free group, which was significantly different (P = 0.001). Anemia was found to be an independent risk factor for nonfatal coronary events in PCI patients (odds ratio: 2.24, 95% confidence interval: 1.05-4.79; P = 0.036). In conclusion, anemia is an important risk factor for predicting nonfatal coronary events after PCI. Although previous studies have shown its impact on fatal events, this study has demonstrated that anemia also has a role in nonfatal thrombotic coronary events and restenosis.