This is a prospective cohort study to examine the efficacy of ESMR application in patients with refractory angina despite optimal medical therapy, not suitable for further PCI or CABG. Characteristics such as angina class scores (CCS class score), nitroglycerin consumption and hospitalization were compared at baseline and 1, 6 and 12 months after ESMR therapy. The effect on cardiac perfusion was assessed at 6 months.

Inclusion Criteria:

• history of coronary artery disease;
• refractory angina pectoris, defined as the persistence of a angina pectoris (Canadian Cardiovascular Society class ≥ 2) for more than 3 months, despite the use of optimal medical therapy (which included β blockers, calcium channel blockers, long-acting nitrates, ivabradine, ranolazine and trimetazidine, up-titrated to the maximal tolerated dose) and coronary disease not amenable for further revascularization (as determined by an interventional cardiologist and cardiac surgeon);
• stable maximal medical therapy for at least 6 weeks;
• stress-induced ischemia at baseline SPECT;
• left ventricular ejection fraction higher than 40%;
• age higher than 18 years.

Exclusion Criteria:

• myocardial infarction or unstable angina in the previous 3 months,
• acute myocarditis, pericarditis, left ventricular thrombus, cardiac malignancies, chronic pulmonary disease (including emphysema and pulmonary fibrosis), endocarditis
• pregnancy