Chest pain without ST elevation: a continuing challenge

Excerpt

Of the many patients with chest pain who are referred to hospitals, only a minority has ST elevation on ECG. Of the other majority, diagnoses include non-ST-elevation myocardial infarction, unstable angina and non-cardiac disease. In this majority, making an accurate diagnosis and risk stratification are very important and several tools have been described and recommended to predict prognosis and select optimal treatment. The optimal treatment includes both medication and (timing of) revascularisation. Several risk scores can be used to identify high-risk patients, including the HEART score, using History, ECG, Age, Risk factors and Troponin [1]. In this issue of the Journal, the prognostic value of the GRACE and TIMI risk scores are confirmed in a registry with a 10-year follow-up [2]. After multivariate analyses, the GRACE risk score was still a predictor of long-term mortality. The researchers from Amsterdam and Alkmaar also found that neither dobutamine stress echocardiography nor myocardial perfusion scintigraphy were predictors of long-term mortality. In their discussion, the authors mainly focus on the lack of predictive value of the non-invasive imaging of coronary artery disease in the study population. They do not suggest to use either the TIMI or the GRACE risk score (or both), and they do not discuss the differences between the two models. The strength of the reported study is the almost complete long-term follow-up. However, the study has several limitations, and the authors discuss some in their limitations section. Major limitations were the lack of data on (additional) revascularisation and other clinical events during follow-up and the very limited (and probably selected) patients who had myocardial perfusion scintigraphy. In fact, with these data no conclusion can be made about the prognostic value of scintigraphy in these patients. Another limitation, inherent to all studies with long-term follow-up, is the fact that time has changed and newer diagnostic tools are now available. Possibly, newer laboratory measurements, including high sensitive troponin and pro-B-type brain natriuretic peptide (BNP), can more accurately identify patients with increased risk [3]. Also newer imaging techniques are now more widely available, including CT [4] and MR [5]. …