Abstract 4175: Quantitative Assessment of Myocardial Blood Flow Using Adenosine Triphosphate Stress Multidetector-row Computed Tomography in Coronary Artery Disease

Abstract

Introduction: The purpose of this study was to test the hypothesis that cardiac multidetector-row computed tomography (MDCT) technology can assess myocardial perfusion quantitatively using adenosine triphosphate (ATP) load technique. Methods: Ten patients (median age 71 (range 65–79) years) who were scheduled for surgical revascularization, underwent cardiac electrocardiography-gated MDCT using ATP-load technique. The patients with unstable angina and myocardial infraction were excluded. Myocardial infarction was detected by late gadolinium enhancement MRI which was assessed before MDCT. Myocardial blood flow (MBF) was estimated from the slope of the linear regression equation with Patlak plots analysis. MBF results were compared to the presence of stenoses more than 75% on coronary angiography (CAG) and moderate to severe myocardium ischemia on stress thallium-201 myocardial perfusion scintigraphy (MPS). Results: The overall mean MBF was 1.64±0.61 ml/g/min. Mean MBF in territories with stenosis on CAG was 0.81±0.49 ml/g/min, while mean MBF in territories without stenosis was 1.83±0.64 ml/g/min (p<0.01). Mean MBF in territories with moderate to severe ischemia on MPS was 0.76±0.49 ml/g/min, while mean MBF in territories without ischemia was 2.15±0.66ml/g/min (p<0.01). When the cut off value of MBF was set at 1.5 ml/g/min, there was good correlation between MBF vs CAG, and MBF and MPS. MBF vs CAG: sensitivity=71.4%, specificity=82.6%; MBF vs MPS: sensitivity=85.7%, specificity=87.0%. Conclusions: This study proposed the possibility of MDCT to quantify myocardial blood flow using ATP in coronary artery disease. Our data suggested that the ATP stress MDCT has an advantage in the assessment of CAD to evaluate both coronary artery stenoses and myocardial perfusion information in one modality.