Efficacy of the COronary SInus Reducer in Patients With Refractory Angina II

To demonstrate the safety and effectiveness of the Reducer system for treatment of patients with refractory angina pectoris treated with maximally tolerated guideline-directed medical therapy who demonstrate objective evidence of reversible myocardial ischemia in the distribution of the left coronary artery and who are deemed unsuitable for revascularization. A non-randomized single-arm will further assess the safety and effectiveness of the Neovasc Reducer System in selected subjects with reversible myocardial ischemia in the distribution of the right coronary artery and who are deemed unsuitable for revascularization, subjects with reversible myocardial ischemia without documented obstructive coronary disease and subjects who cannot complete an exercise tolerance test due to an above-the-ankle amputation.