International prospective cohort study of microvascular angina - Rationale and design.

Background: Patients with signs and symptoms of myocardial ischemia and non-obstructive coronary artery disease (CAD) frequently have coronary functional abnormalities, including coronary microvascular dysfunction. Those with the latter are grouped under the term "microvascular angina" (MVA). Although diagnostic criteria exist for MVA, as recently proposed by our COVADIS (COronary VAsomotor Disorders International Study) group and the condition has been increasingly recognized in clinical practice, the clinical characteristics and long-term prognosis of MVA patients in the current era remain to be fully elucidated.