Background: Patients with unstable angina (UA) and non-ST-elevation myocardial infarction (NSTEMI) remain at risk for death and cardiac ischemic events after being discharged from the hospital.
Methods: We examined whether the Thrombolysis In Myocardial Infarction (TIMI) risk score for UA/NSTEMI, ascertained at presentation in patients enrolled in the TIMI 11B and Efficacy and Safety of Subcutaneous Enoxaparin in Unstable Angina and Non-Q-Wave MI (ESSENCE) trials, could be used to identify patients at high risk for major cardiac events after hospital discharge.
Results: There were a total of 1218 major cardiac events, defined as death, nonfatal myocardial infarction, or urgent revascularization, by day 43. Of these events, 336 (28%) occurred in patients after they were discharged from the hospital. Use of the TIMI risk score for UA/NSTEMI revealed a progressive, statistically significant increase in the rate of events after leaving the hospital as the patients' baseline level of risk increased (P <.001 for chi(2) test for trend). For patients with a risk score of 5 to 7, treatment with enoxaparin during the acute phase was associated with an odds ratio of 0.51 (95% CI 0.29-0.91) for the occurrence of death and cardiac ischemic events after hospital discharge.
Conclusions: More than one fourth of the major cardiac events that will occur in the first 6 weeks occur after discharge from the hospital. Stratification at presentation on the basis of the TIMI risk score for UA/NSTEMI can be used to identify patients at high risk for these events. Among patients at high-risk, acute-phase treatment with enoxaparin significantly reduces the risk of major cardiac events after leaving the hospital.