Angina pectoris and myocardial ischemia in the absence of obstructive coronary artery disease: practical considerations for diagnostic tests. 
Angina and myocardial ischemia without obstructive coronary artery disease are common clinical findings, often neglected for the assumption of a good prognosis.  Most often, such patients are neither further investigated nor offered specific treatment beyond reassurance.  However, the absence of significant coronary stenoses on angiography does not necessarily imply a "healthy" coronary tree.  In such cases, myocardial ischemia may result from different types of functional disease involving the epicardial coronary arteries, the coronary microcirculation, or both; an accurate assessment of these components should be systematically performed after exclusion of organic epicardial disease because a correct diagnosis has relevant prognostic and therapeutic implications.  Here we discuss the basic principles of diagnostic tests in this setting and propose a diagnostic sequence of reasonable practical implementation that may help identify patients at risk of future cardiac events.