Self-Expanding Coronary Sinus Reducer for Treatment of Symptomatic Coronary Microvascular Dysfunction (CMD) (SERRA-I Study)

Exclusion criteria

• . Significant obstructive epicardial disease (greater than 50% diameter stenosis) that can be treated with PCI or CABG as determined by Investigator and confirmed by the Central Screening Committee.
• . Recent (less than 30 days before index procedure) troponin or CKMB positive acute coronary syndrome (NSTEMI or STEMI) with evidence of ischemia.
• . Extra-coronary contributory causes of angina - e.g., untreated hyperthyroidism, anemia (Hgb less than 9 g/dL), uncontrolled hypertension (systolic blood pressure greater than 160 mmHg or diastolic blood pressure greater than 100 mmHg despite medications), atrial fibrillation with a rapid ventricular response (consistently greater than 100 bpm despite medications) or other tachyarrhythmia, severe aortic stenosis, decompensated heart failure, hypertrophic cardiomyopathy with left ventricular outflow tract obstruction or asymmetric septal hypertrophy (concentric left ventricular hypertrophy is not an exclusion criterion).
• . NYHA class IV or decompensated HF or hospitalization due to HF during the 90 days before the index procedure.
• . Life-threatening rhythm disorders or any rhythm disorders that would require cardiac resynchronization therapy or lead placement in the coronary sinus.
• . Severe chronic obstructive pulmonary disease (COPD) as indicated by a forced expiratory volume in one second (FEV1) of less than 1.0L or need for home daytime oxygen or regular oral steroids.
• . Severe valvular heart disease (any valve).
• . Moderate (TAPSE\<12) or severe RV dysfunction (TAPSE\<8) by echocardiography.