Abstract P105: Clinical Factors Associated With Left Ventricular Ejection Fraction Disparity in Patients With Left Ventricular Dysfunction Undergoing Multimodality Imaging

Background: Drug and device therapy of heart failure is increasingly determined based on left ventricular ejection fraction (LVEF) partition values. Many patients undergo both single photon emission computed tomography (SPECT) and echocardiographic assessment of LVEF. Significant disparity frequently exists between these 2 techniques, even when testing is performed near simultaneously in clinically stable patients. Objective: We aimed to determine clinical predictors of LVEF disparity in patients undergoing multimodality testing. Methods: Between January 2006 and July 2007, 2937 patients underwent both echo and SPECT testing within a 7 day period. Of these, 119 patients had an LVEF <50% by 1 or both techniques, and an absolute LVEF difference between the 2 techniques of at least 10%. A control group comprising of 118 patients had an LVEF <50% by 1 or both techniques, and an absolute LVEF difference between the 2 techniques of less than 10%. In a logistic model with a stepwise selection method 30 candidate clinical variables were available to be selected in the model. Results: The predictive model resulted in five variables: Atrial Fibrillation, Severe mitral regurgitation, Left ventricular hypertrophy, high basal heart rate during echocardiogram and Paced rhythm. The model obtained good predictability(c=0.82) and fit (Hosmer-Lemeshow p=0.51). The point estimates and odds ratios are shown in the figure below. Conclusions: In patients with LVEF < 50%, atrial fibrillation, severe mitral regurgitation, left ventricular hypertrophy, high basal heart rate during echocardiogram and paced rhythm are associated with a >10% LVEF disparity between the two imaging techniques.