Microvascular angina and microvascular dysfunction - Current review of the literature

Microvascular angina refers to chest pain associated with coronary microvascular dysfunction (CMD). A new paradigm in cardiology was entrenched when the WISE studies demonstrated that angina may be present in patients with non-obstructive coronary artery disease (NOCAD). Statistically, there is a higher number of cases in women. The prevalence of NOCAD has been perceived in recent years reaching up to 20-30% of all coronary artery disease CAD. 60% of the patients with angina symptoms may not present any sign of obstructive coronary artery disease (OCAD). In 2015, the COVADIS group established diagnostic criteria for microvascular angina. Recent studies used these criteria to design randomized clinical trials to elucidate the prevalence, diagnosis, treatment and prognosis of this entity. Conventional invasive angiography suggests that up to two-thirds of patients with NOCAD may have CMD, however this test does not allow direct visualization of the microcirculation. Non-invasive imaging modalities such as Positron Emission Tomography (PET) enable a direct and accurate assessment of coronary microvascular function. Thus, PET is becoming an indispensable tool in the evaluation of suspected CMD.