%0 Journal Article %A G A Lanza %T Cardiac syndrome X: a critical overview and future perspectives %D 2007 %R 10.1136/hrt.2005.067330 %J Heart %P 159-166 %V 93 %N 2 %X The classic definition of cardiac syndrome X (CSX) seems inadequate both for clinical and research purposes and should be replaced with one aimed at including a sufficiently homogeneous group of patients with the common plausible pathophysiological mechanism of coronary microvascular dysfunction. More specifically, CSX should be defined as a form of stable effort angina, which, according to careful diagnostic investigation, can reasonably be attributed to abnormalities in the coronary microvascular circulation. %U https://heart.bmj.com/content/heartjnl/93/2/159.full.pdf