Abstract
BACKGROUND: Although the Thrombolysis In Myocardial Infarction (TIMI) score incorporates ST deviation, it does not account for characteristics of the ST deviations. In the present study, it was hypothesized that the magnitude and characteristics of ST deviation may add to the prognostic values of the TIMI risk score in acute coronary syndrome (ACS) patients, particularly in lower-risk patients with a TIMI risk score of less than 5. OBJECTIVE: To evaluate the prognostic value of combining the TIMI risk score and characteristics of ST deviation in patients with non-ST elevation ACS and a TIMI risk score of less than 5. METHODS: The death/myocardial infarction (MI) rates of 1296 patients enrolled in the Platelet Receptor Inhibition in Ischemic Syndrome Management in Patients Limited by Unstable Signs and Symptoms (PRISM-PLUS) angiographic substudy were examined. RESULTS: Patients without a TIMI risk score of 5 or greater, and without an ST deviation of 1 mm or greater had the lowest six-month rate of death/ MI (5%). In patients with a TIMI risk score of less than 5, the six-month death/MI rate was increased in those with ST depression of 2 mm or greater compared with patients with a similar TIMI risk score and without ST deviation of 1 mm or greater (24% versus 5%, P<0.001). The presence of ST deviation of 2 mm or greater identified an additional 15% of patients with an increased six-month death/MI rate in patients with a TIMI risk score of less than 5. CONCLUSION: ST segment deviation of 2 mm or greater confers additional prognostic information in non-ST elevation ACS patients with a TIMI risk score of less than 5. Patients with a TIMI risk score of less than 5 and ST deviation of 2 mm or less had the lowest risk of six-month death/MI.