What is the Thrombolysis In Myocardial Infarction (TIMI) ST-Elevation Myocardial Infarction (STEMI) risk score?

From the Guidelines

The TIMI STEMI Risk Score is a crucial tool for predicting 30-day mortality in STEMI patients, and it should be used to guide treatment decisions, including the aggressiveness of reperfusion therapy and the need for adjunctive therapies. The TIMI Risk Score is determined by the sum of the presence of 7 variables at admission, including age 65 years or older, at least 3 risk factors for coronary artery disease, prior coronary stenosis of 50% or more, ST-segment deviation on ECG presentation, at least 2 anginal events in the prior 24 hours, use of aspirin in the prior 7 days, and elevated serum cardiac biomarkers 1. The score ranges from 0 to 7 points, with higher scores indicating greater mortality risk, as shown in the table:

• 0-1 points: 4.7% risk of all-cause mortality, new or recurrent MI, or severe recurrent ischemia requiring urgent revascularization through 14 days after randomization
• 2 points: 8.3% risk
• 3 points: 13.2% risk
• 4 points: 19.9% risk
• 5 points: 26.2% risk
• 6-7 points: 40.9% risk 1. The TIMI Risk Score has been validated internally within the TIMI 11B trial and 2 separate cohorts of patients from the ESSENCE trial, and it remains a significant predictor of events, even with missing information 1. Some of the key points to consider when using the TIMI Risk Score include:
• The score is simple to calculate and can be used at the bedside
• It provides a quick and accurate assessment of mortality risk
• It can be used to guide treatment decisions, including the aggressiveness of reperfusion therapy and the need for adjunctive therapies
• It has been validated in multiple studies and remains a significant predictor of events. Overall, the TIMI STEMI Risk Score is a valuable tool for clinicians to use in the management of STEMI patients, and it should be used in conjunction with other clinical factors to guide treatment decisions 1.

From the Research

Overview of TIMI STEMI Risk Score

• The TIMI STEMI Risk Score is a convenient, bedside, clinical score for risk assessment at presentation of patients with ST-elevation myocardial infarction (STEMI) 2.
• The score was developed as the simple arithmetic sum of independent predictors of mortality weighted according to the adjusted odds ratios from logistic regression analysis 2.

Predictive Value of TIMI STEMI Risk Score

• The TIMI Risk Score accurately predicts risk of death in 30-day and one-year follow-up in STEMI patients treated with primary percutaneous coronary interventions 3.
• The score has good power to predict 30-day (c statistic 0.834) as well as one-year mortality (c statistic 0.809) 3.
• The TIMI risk score for STEMI predicts in-hospital mortality and adverse events in patients without cardiogenic shock undergoing primary angioplasty 4.
• However, the validity of this risk score in patients with STEMI with reduced left ventricular ejection fraction (LVEF) remains unclear, and it demonstrates poor discrimination in predicting mortality or recurrent MI in this population 5.

Components and Calculation of TIMI STEMI Risk Score

• The TIMI Risk Score for STEMI was created as the simple arithmetic sum of independent predictors of mortality weighted according to the adjusted odds ratios from logistic regression analysis 2.
• Ten baseline variables, accounting for 97% of the predictive capacity of the multivariate model, constituted the TIMI risk score 2.
• The risk score showed a >40-fold graded increase in mortality, with scores ranging from 0 to >8 (P:<0.0001); mortality was <1% among patients with a score of 0 2.

Clinical Utility of TIMI STEMI Risk Score

• The TIMI risk score for STEMI captures the majority of prognostic information offered by a full logistic regression model but is more readily used at the bedside 2.
• This risk assessment tool is likely to be clinically useful in the triage and management of fibrinolytic-eligible patients with STEMI 2.
• The TIMI Risk Score accurately defines the population of STEMI patients who are at high risk of death not only during the first 30 days, but also during a long-term follow-up 3.