Évaluation de la perfusion et de la fonction contractile du myocarde à l’aide de l’analyse de Karhunen-Loeve en tomographie d’émission monophotonique myocardique synchronisée à l’ECG

Abstract

Goal We evaluated the diagnostic performance of the Karhunen–Loeve transform applied to myocardial gated SPECT. The previous studies showed that KLT images characterize myocardial perfusion (KL0) and contractile function (KL1). Method and material 99mTc-gSPECT studies were performed in 101 patients (121 acquisitions) with suspected or known coronary artery disease. The images were evaluated using a five-point scoring system dividing the left ventricle into 11 segments. We compared the scores obtained by this semi-quantitative visual analysis of gSPECT and KLT images. Results and discussion The agreement for perfusion and thickening scores was 94 and 95% respectively. Quantitative evaluation of KL0 and KL1 images by univariate and multivariate analysis was performed in the left ventricular ROI. Discriminant analysis characterized the acquisitions as normal or pathologic with a sensitivity of 95% and a specificity of 96% and positive and negative predictive values of 96 and 95%. These selection criteria were tested prospectively in 52 patients with similar results. KLT generates a synthesis of left ventricular perfusion and kinetics. It facilitates discrimination between normal and pathological acquisitions with high predictive values.