Optimal Diagnosis and Therapy of microvascular Angina pectoris

Patients with microvascular angina are characterized by angina pectoris with proof of myocardial ischemia in the absence of any relevant epicardial stenosis and without myocardial disease (type 1 coronary microvascular dysfunction according to Crea and Camici). Structural and functional alterations of the coronary microvessels (diameter < 500 μm) are the reason for this phenomenon. Frequently such alterations are associated with cardiovascular risk factors. Patients with angina pectoris without epicardial stenoses represent for 10 - 50 % of all patients undergoing coronary angiography depending on the clinical presentation. Diagnostic approaches include non-invasive (e. g. combination of coronary CT-angiography and positron emission tomography/echo Doppler-based coronary flow reserve measurements) as well as invasive procedures (coronary flow reserve measurements in response to adenosine, intracoronary acetylcholine testing). Pharmacological treatment of these patients is often challenging and should be based on the characterization of the underlying mechanisms. Moreover, strict risk factor control and individually titrated combinations of antianginal substances (e. g. beta blockers, calcium channel blockers, nitrates, ranolazine, ivabradine etc.) are recommended.