Abstract 16861: Athens QRS Score an Independent Predictor of Coronary Artery Disease Detection in Patients With Otherwise Normal Exercise Stress Test
Background: Exercise ECG has a significant diagnostic and prognostic value for coronary artery disease (CAD) detection, especially when parameters such as exercise induced Q, R and S wave amplitude changes are incorporated to ST depression criteria. Literature has revealed the value of Athens QRS score (AVF+V5) in conjunction with ST depression. We aim to determine the predictive and diagnostic value of Athens QRS score in patients with otherwise normal exercise stress test (EST), as it has not been evaluated before.
Methods: A retrospective analysis of 458 patients who underwent EST or Myocardial Perfusion Imaging Bruce protocol within 2 months of coronary angiography from 2008 until 2011 was conducted. Patients (n=173) with abnormal stress test based on ST segment criteria were excluded. QRS score was calculated using exercise-induced Q, R, S wave amplitude changes and ≤ 5 was defined as abnormal. Stenosis of ≥70 in any major vessel and ≥50 in the left main was considered as obstructive CAD. Thus, our study cohort consisted of 285 patients and was divided into 2 groups: group I, n=56 patients with abnormal QRS scores and group II, n=229 patients, with normal QRS scores. Angiography results were evaluated in both groups.
Results: Demographics of the study cohort; Mean age 55±9.7, 51 % males, 55% Hispanics, 36% African Americans, 83% hypertensive, 60% diabetics, 53% dyslipidemic, 54% obese, mean BMI 30±5.3, 0.4% history of myocardial infarction, and 17% smokers, were similar between the two groups (p>0.05). Group I had significantly lower mean QRS score (0.8±1.9 vs 11±2.3, p<0.001) and a higher incidence of single vessel disease (VD) as well as multi-VD (52% vs 8% and 34% vs 1.8%respectively, p<0.001). The overall risk of having any type of obstructive CAD was higher in group I compared to group II (86% vs 8%, p<0.001). Additionally, on stepwise logistic regression analysis, QRS scores correlated significantly with incidence of CAD (OR=1.610, 95% CI=1.445[[Unable to Display Character: –]]1.794, p<0.001).
Conclusion: Athens QRS score is an independent predictor of CAD. Patients with low QRS scores warrant further evaluation even with reassuring exercise stress test results.
- © 2013 by American Heart Association, Inc.