A Study to Evaluate the Feasibility and Effectiveness of Coronary Sinus Narrowing in Patients with Coronary Microvascular Dysfunction


About this study

The purpose of this study is to evaluate the impact of the Neovasc Reducer™ device implantation on coronary microvascular function.  It will be assessed invasively by measurement of coronary flow reserve (CFR) and the index of myocardial resistance (IMR) in patients with angina but no-obstructive coronary artery disease (ANOCA) and documented coronary microvascular dysfunction (CMD) [CFR ≤ 2.5 and/or IMR ≥ 25].

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria

- Age >18

- Able to provide written informed consent and willing to participate in all required
study follow-up assessments

- Symptomatic CAD with refractory angina defined as CCS class II to IV, despite optimal
tolerated medical therapy

- Abnormal coronary microvascular function indices: CFR≤2.5 and/or IMR≥25

Exclusion Criteria

- Recent (within 3 months) acute coronary syndrome

- Patients with prior coronary artery bypass surgery

- Unstable angina (recent onset angina, crescendo angina, or rest angina with ECG
changes) during the last 30 days

- Subjects in cardiogenic shock (systolic pressure < 80mm/Hg, on vasopressors or
intraaortic counter pulsation) at the time of consenting. Subjects who recover from
cardiogenic shock by the time of consenting are eligible.

- Obstructive CAD on coronary angiography (>70% stenosis or 50-70% stenosis with
iFR<0.89 or FFR<0.8 in epicardial artery)

- Inability to perform invasive coronary flow evaluation and/or measure CFR and IMR in
the LAD

- Severe valvular heart disease

- LVEF<30%

- Decompensated congestive heart failure (CHF) or hospitalizatoin due to CHF during the
last 3 months

- Patient with a pacemaker electrode in the CS

- Mean right atrial pressure >15 mmHg

- Anomalous or abnormal CS anatomy (e.g., tortuosity, aberrant branch, persistent left
superior vena cava (SVC) as demonstrated on angiogram

- CS diameter at the site of planned implantation greater than 13mm or less than 9.5 mm
as measured by angiogram

- Severe chronic obstructive pulmonary disease (COPD) indicated by a forced expiratory
volume in one second that is less than 55 percent of the predicted value

- Tricuspid valve replacement or repair (tissue or mechanical)

- Chronic renal failure (serum creatinine >2mg/dL), and or on chronic hemodialysis

- Moribund, or with comorbidities limiting life expectancy to less than one year

- Known severe reaction to required procedural medication

- Known allergy to stainless steel or nickel

- Magnetic Resonance Imaging (MRI) within 8 weeks of Reducer implantation

- Participation in another ongoing investigational trial

- Additional factors deemed unsuitable for trial enrollment per discretion of principal

- Inmates

Note: Other protocol defined Inclusion/Exclusion criteria may apply.

Eligibility last updated 10/5/22. Questions regarding updates should be directed to the study team contact

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Amir Lerman, M.D.

Closed for enrollment

Contact information:

Diana Albers

(507) 255-6884


More information


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