Correlation of Clinical Risk Scores for Unstable Angina with the Angiographic Extent and Severity of Coronary Artery Disease

Abstract

In patients presenting with Unstable Angina the correlation of clinical risk predictors and clinical risk scores with angiographic extent of Coronary Artery Disease (CAD) is less well understood. The objective is to assess the correlation of various clinical risk scores for unstable angina and individual clinical risk factors with the extent and severity of coronary artery disease as assessed by coronary angiography. The present study was a single centre, hospital based, observational, cross-sectional, descriptive study conducted at a tertiary care teaching and research institute in South India. One hundred and fifty patients presenting with chest pain consistent with unstable angina were assessed for existence of independent clinical predictors and calculations were done for their 5 clinical risk scores. Coronary angiography was performed in all the patients leading to the generation of Modified Gensini score and its correlation with the various clinical risk scores was done. Presence of dyslipidemia and diabetes were stronger predictors of Modified Gensini score. TIMI, GRACE& HEART risk scores had moderate correlation with angiographic severity while FRISC and PURSUIT scoring systems had a weak correlation. Presence of dyslipidemia and diabetes significantly affect the extent of CAD. Thus their presence in patients presenting with unstable angina assign them to the high risk category. Angiographic extent of CAD was strongly correlated with TIMI, GRACE and HEART risk scores, thus emphasizing on their use in risk stratification and in identifying the category of patients likely to make the most out of an early invasive strategy.