MATERIALS AND METHODS

This case-control study was previously approved by the institutional ethics committee and involved 21 patients referred for coronary angiography to evaluate coronary artery disease. The inclusion criteria were angina, a myocardial perfusion defect (stress imaging test) and normal coronaries (coronary angiography). The exclusion criteria were myocardial infarction in the last 60 days, heart transplantation, a revascularization procedure, left ventricular dysfunction, systemic inflammatory diseases, autoimmune diseases, obesity, smoking, hematological disorders, hemodialysis and the current use of anticoagulant, corticosteroid or immunosuppressive therapy.