Assessing Risk in ACS – Risk Scores More Reliable

How well do physicians assess risk in non-ST elevation (NSTEMI) acute coronary syndrome (ACS) patients? Recent studies have suggested that often high-risk patients are the ones who receive less aggressive therapy – the so called “treatment-risk paradox”. This study sought to identify the patient characteristics that physicians considered to be high-risk, and to examine how patient risk assessment by physicians related to objective risk score evaluation and eventual treatment.

The prospective Canadian ACS 2 Registry included 1956 patients admitted for NSTEMI over a 15 month period.Treating physicians’ patient risk assessments were recorded and compared against several well established risk scales: TIMI (Thrombolysis in Myocardial Infarction), GRACE (Global Registry of Acute Coronary Events), and PURSUIT (Platelet glycoprotein IIb/IIIA in Unstable Angina: Receptor Suppression Using Integrilin Therapy).

Of the 1956 patients, 17.8% were classified as low risk, 42.0% as intermediate risk, and 40.2% as high risk by their treating physicians. Only weak correlations were found between risk assessment by physicians and the three risk scores used. Multivariable analysis demonstrated that physicians associated a history of stroke, a high Killip class, ST-segment changes, T-wave inversion, and positive cardiac biomarkers with high-risk. Established prognostic markers, including a history of heart failure, heart rate, systolic blood pressure, and creatinine levels, were not linked to high-risk.

NSTEMI ACS patients can present with a variety of symptoms, some more subtle than others. This study suggests that physicians would be well advised to standardize their assessment process by using the TIMI, GRACE, or PURSUIT risk scores – an approach recommended by both the American Heart Association and American College of Cardiology.

  • Yan AT, Yan RT, Huynh T, et al. Understanding physicians’ risk stratification of acute coronary syndromes. Arch Intern Med 2009; 169: 372-378.