Impact of Early Invasive Approach on Outcomes of Patients With Acute Coronary Syndrome and Baseline Anemia: Analysis From the ACSIS Registry. 
Anemia in patients with acute coronary syndromes (ACS) is strongly related to the increased risk of bleeding and mortality.  Whether benefit of early invasive strategy exceeds the risk of bleeding in these patients is unknown.  To assess impact of early coronary angiography on outcomes of patients with ACS and baseline anemia.  Biennial Israeli ACS registry (ACSIS) prospectively collects data from all 26 public hospitals.  The endpoints included rates of in-hospital major bleeding, as well as 30-day and 1-year mortality.  Anemia at baseline was present in 1,464 of 5,600 patients with ACS (26.1%).  Coronary angiography within index hospitalization was performed less frequently in patients with anemia (76.6% vs. 90.8%, P < 0.001).  Non-performance of coronary angiography was associated with older age and higher prevalence of comorbidities.  Among patients with anemia who underwent coronary angiography, the majority (95.5%) had obstructive coronary disease, of whom 77.8% were triaged to revascularization.  Performance of coronary angiography was associated with significantly lower (P < 0.0001) rates of mortality at 30 days (5.7% vs. 15.6%) and at 1 year (11.9% vs. 34.1%).  Major bleeding occurred with similar incidence in groups with and without coronary angiography (3.1% vs. 3.8%, respectively; P = 0.54).  By multivariable analysis, performance of coronary angiography was an independent predictor of lower 1-year mortality (hazard ratio [95%CI] = 0.30 [0.21, 0.44].  In the setting of ACS, despite the presence of baseline anemia, early coronary angiography with subsequent revascularization, when indicated, was associated with improved clinical outcomes including 1-year mortality without significant increase in rates of major bleeding.