Incidence, outcomes, and management of bleeding in non-ST-elevation acute coronary syndromes
ABSTRACTAntithrombotic and antiplatelet drugs and percutaneous interventions have decreased the ischemic outcomes of non-ST-elevation acute coronary syndromes, but they pose risks of bleeding. The authors review the scope of the problem and ways to prevent and manage bleeding in this situation.
KEY POINTS
- The reported incidence of bleeding after treatment for non-ST-elevation acute coronary syndromes ranges from less than 1% to 10%, depending on a number of factors.
- Bleeding is strongly associated with adverse outcomes, although a causal relationship has not been established.
- Patients should be assessed for risk of bleeding so that the antithrombotic and antiplatelet regimen can be adjusted, safer alternatives can be considered, and percutaneous interventions can be used less aggressively for those at high risk.
- If bleeding develops and the risk of continued bleeding outweighs the risk of recurrent ischemia, antithrombotic and antiplatelet drug therapy can be interrupted and other agents given to reverse the effects of these drugs.
Blood transfusion
Long considered beneficial to critically ill patients, blood transfusion to maintain hematocrit levels during acute coronary syndromes has come under intense scrutiny. Randomized trials have shown that transfusion should not be given aggressively to critically ill patients.60 In acute coronary syndromes, there are only observational data.
Rao et al61 used detailed clinical data from 24,112 patients with acute coronary syndromes in the GUSTO IIb, PURSUIT, and PARAGON B trials to determine the association between blood transfusion and outcomes in patients who developed moderate to severe bleeding, anemia, or both during their hospitalization. The rates of death in the hospital and at 30 days were significantly higher in patients who received a transfusion (30-day mortality HR 3.94; 95% CI 3.36–4.75). However, there was no significant association between transfusion and the 30-day mortality rate if the nadir hematocrit was 25% or less.
Of note: no randomized clinical trial has evaluated transfusion strategies in acute coronary syndromes at this time. Until such data are available, it is reasonable to follow published guidelines and to avoid transfusion in stable patients with ischemic heart disease unless the hematocrit is 25% or less.31 The risks and benefits of blood transfusion should be carefully weighed. Routine use of transfusion to maintain predefined hemoglobin levels is not recommended in stable patients.
