For NSTEMI, which risk stratification tool guides an early invasive strategy, and what thresholds indicate high risk?

• A. TIMI or GRACE risk scores; high risk indicated by TIMI ≥5 or GRACE ≥140
• B. CHADS-VASc score; high risk CHADS-VASc ≥3
• C. MELD score; high risk MELD ≥15
• D. APACHE II score; high risk APACHE II ≥15

Answer: (A)

In NSTEMI, deciding how quickly to intervene hinges on risk stratification to identify patients who would benefit most from an early invasive approach (angiography within 24 hours). The two most commonly used tools for this are the TIMI and GRACE risk scores. The TIMI risk score for NSTEMI/UA uses seven factors (such as age, CAD risk factors, known CAD, aspirin use in the past week, severe angina, ST changes, and elevated biomarkers). A score of 5 or more places a patient in the high-risk category, supporting early invasive management.

The GRACE score estimates the risk of mortality and uses variables like age, heart rate, systolic blood pressure, creatinine, presentation with cardiac arrest, ST-segment deviation, elevated enzymes, and Killip class. A GRACE score of 140 or higher is considered high risk and also indicates benefit from urgent invasive evaluation.

Other scoring systems mentioned in different clinical contexts, such as CHADS-VASc (stroke risk with atrial fibrillation), MELD (liver disease severity), and APACHE II (ICU severity), do not apply to risk stratification for invasive management in NSTEMI.