Risk stratification in the patient with unstable angina or non ST elevation MI
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Definition
- Unstable angina: acute ischemic symptoms, with or without EKG changes (ST depression/transient ST elevation/new T wave inversion), and absence of troponin or CK-MB elevation.
- Non ST elevation MI: acute ischemic symptoms, with or without EKG changes (ST depression/transient ST elevation/new T wave inversion), and presence of troponin or CK-MB elevation.
Risk stratification in patient with UA/NSTEMI
- The Thrombolysis in Myocardial Infarction (TIMI) risk score for UA/NSTEMI:
- The TIMI risk score for STEMI was created from simple arithmetic sum of independent predictors of mortality weighted according to the adjusted odds ratios from logistic regression analysis.
- The patient pool (n=1957) came from the TIMI 11B trial.
- The TIMI risk score was subsequently validated using the unfractionated heparin group from the ESSENCE trial and the enoxaparin groups from both the TIMI 11B and the ESSENCE trials.
- TIMI risk score of 0-2 = low risk, TIMI risk score of 3-4 = moderate risk, TIMI risk score of 5-7 = high risk.
- ACC/AHA/SCAI 2005 guideline update for percutaneous coronary intervention:
- The guideline defined high risk as elevated cardiac enzymes, ST segment depression, recurrent angina, hemodynamic instability, sustained VT/VF, history of DM, prior PCI in the past 6 months or CABG.
Early invasive strategy vs non-invasive strategy
- TACTICS-TIMI 18: In patients with UA/NSTEMI who was treated with tirofiban, the use of early invasive strategy reduce the rate of the primary end point (death, non-fatal MI, and rehospitalization for ACS at 6 months) from 19.4% to 15.9%.