Abstract 210: Coronary Artery Luminal Diameter, False Positive Stress Myocardial Perfusion Imaging and Body Mass Index: Is There an Association?

Abstract

Background: Single Photon Emission Computerized Tomography Myocardial Perfusion Imaging (MPI) stress test is a widely used test to evaluate patients with suspected CAD with relatively higher false positive rate. There is a paucity of data on the association of false positive MPI, coronary artery diameter particularly focusing on left anterior descending artery (LAD) and body mass index (BMI). Methods: An institutional review board approved, retrospective study included female patients with abnormal MPI stress tests showing reversible ischemia in the anterior walls but without any disease in LAD arteries as assessed by coronary angiography within 3 months of the stress tests. Two qualified physicians reviewed the cine-angiograms and LAD diameter was categorized into two groups 3 mm and 3 mm. Categorical and continuous variables were analyzed using chi -square test and analysis of variance test respectively with a p value for significance as < 0.05. Results: A total of 251 female patients who had both false positive MPI stress test and normal coronary angiograms were analyzed. The mean (±SD) age, BMI and left ventricular ejection fraction (LVEF) was 59.9±12.3 years, 34.1±9.5 kg/m 2 and 59.4±7.2 % respectively. There was 76% of the patients had LAD diameter of ≥3 mm and 24% had < 3 mm. There was no statistically significant difference in mean age, BMI and LVEF between the two groups of the vessel sizes. The mean age was 60.5±12.5 vs 58.1±11.7 years (p = 0.20) and mean BMI was 33.5±9.3 vs 35.7±10.2 kg/m2 (p = 0.12) in ≥3 mm vs < 3 mm vessels. There was no statistically significant association noted between BMI categories and vessel diameters. When BMI was categorized as < 24.9, 25-29.9, 30-39.9 and > 40, there was 17.6% vs 15.5 %; 22.5% vs 17.2%; 36.4% vs 39.7% and 23.5% vs 27.6% patients had ≥ 3 vs < 3 mm vessels respectively (Chi-square p value = 0.77). Conclusion: There is no association between the luminal diameter of LAD and false positive MPI. Additionally, vessel diameter does not depend upon BMI. Further studies are needed to assess these observations.