Editorial Absolute Quantification of Myocardial Perfusion A Method Proves Its Mettle

Coronary artery disease (CAD) remains the main cause ofdeath in the western world, despite the considerable improvements in its diagnosis and therapy in the past few decades.1 Today, CAD is widely understood to constitute an advanced stage of atherosclerosis,2 that is to say, an inflam-matory pathology involving both coronary and extracoronary arteries.3 The diagnosis of CAD is frequently based on morphological observations obtained through invasive coro-nary angiography (ICA), whereby the presence of at least 1 coronary artery stenosis of at least 50 % and a history of myocardial infarction are considered to be diagnostic. It is increasingly appreciated that perfusion imaging brings addi-tional prognostic value compared with morphological imag-ing alone.4 In particular, perfusion defects can occur at any stage of atherosclerotic disease, from the earliest signs of endothelial dysfunction5,6 to the debut of nonobstructiv