Abstract 5019: A Risk Score for Predicting Obstructive Coronary Artery Disease in Women with Angina
Up to 60% of women who undergo cardiac catheterization for exertional angina have angiographically normal coronary arteries. The aim of this study was to develop a risk score to predict obstructive CAD in women with angina and abnormal stress testing. The medical records of 317 consecutive women with angina and a positive stress test who underwent cardiac catheterization between 2003–2007 at Parkland Hospital were analyzed. Univariable analysis was used to determine the association between various patient characteristics and catheterization result (obstructive disease with a >50% lesion vs. normal coronaries or non-obstructive disease with a <25% lesion). Significant variables were entered into a multivariable logistic regression model to derive a risk score discriminating obstructive CAD. Variables independently associated with obstructive CAD included age >55 (OR =2.1, CI 1.2–3.8), BMI <30kg/m2 (OR =1.9, CI 1.1–3.3), smoking (OR =2.5, CI 1.4 – 4.2), hyperlipidemia (OR =2.6, CI 1.3–5.1), diabetes (OR =1.7, CI 0.98 –2.9), and a positive stress test in the lateral (OR =2.2, CI 1.2– 4.3) or apical (OR =2.1, CI 1.1–3.7) regions. Assigning each variable one point to comprise a “risk score”, there was a graded association between the score and the prevalence of obstructive disease (Figure⇓). An optimized cut-point of a score <4 included 62% of the subjects and achieved a negative predictive value of 78% for obstructive CAD. This simple tool can be used to estimate the risk of obstructive CAD in women with angina. Prospective studies should evaluate whether non-invasive testing such as CT angiography can be used in those with a low risk score.