Mitral Loop Cerclage Annuloplasty for Secondary Mitral Regurgitation

Abstract

OBJECTIVES This is an early feasibility clinical test of mitral loop cerclage annuloplasty to treat secondary mitral valve regurgitation. BACKGROUND Secondary mitral regurgitation is characterized by cardiomyopathy, mitral annular enlargement, and leaflet traction contributing to malcoaptation. Transcatheter mitral loop cerclage applies circumferential compression to the mitral annulus by creating a loop through the coronary sinus across the interventricular septum, protecting entrapped coronary arteries from compression, and interactive annular reduction under echocardiographic guidance. This is the first human test of mitral loop annuloplasty. METHODS Five subjects with severe symptomatic secondary mitral regurgitation underwent mitral loop cerclage, with echocardiographic and computed tomography follow-up over 6 months. RESULTS Mitral loop cerclage was successful in 4 of 5 subjects and aborted in 1 of the 5 because of unsuitable septal coronary vein anatomy. Immediately and over 6 months, measures of both mitral valve regurgitation (effective orifice area and regurgitation fraction) and chamber dimensions (left atrial and left ventricular volumes) were reduced progressively and ejection fractions increased. Two with persistent and permanent atrial fibrillation spontaneously reverted to sinus rhythm during follow-up. One subject experienced a small myocardial infarction from an unrecognized small branch coronary occlusion. Another, experiencing cardiogenic shock at baseline, died of intractable heart failure after 6 weeks. CONCLUSIONS In this first human test, mitral loop cerclage annuloplasty was successful in 4 of 5 attempts, caused reverse remodeling (reduction in secondary mitral regurgitation and heart chamber volumes), and suggested electrical remodeling (reversion of atrial fibrillation). Further evaluation is warranted.

Transcatheter Mitral Valve Repair and Replacement: Analysis of Recent Data and Outcomes

“…1 In 2017, the first-inman results involving 5 patients were published. 47 That study involved 5 patients with severe secondary MR with a primary efficacy endpoint of change in MR severity at 1 month. Importantly, the definition of severe secondary MR included EROA of 0.20 cm 2 .…”

Left ventricular restoration devices post myocardial infarction

“…Because of the coronary artery protection device, it is suitable for a wider range of patients than the previously described devices. It has been investigated in a first-in-human feasibility study on five subjects with severe FMR and NYHA class III or IV, reporting a successful implantation in four subjects, reducing LVEDV and regurgitant volume [ 60 ]. Future studies will have to determine whether a transvenous mitral annuloplasty can be a feasible treatment for patients with ischemic FMR (Table 1 ).…”

“… CARILLON ( NCT03142152 ) Recruiting 1-year freedom from MAE, ∆ regurgitant volume, and clinical composite of death, time to first HF hospitalization and improvement in 6MWT distance 400 (?) Mitral loop cerclage Severe FMR, NYHA class III–IV First-in-human [ 60 ] Completed 1-month freedom from MACE ( 80% ), reduction of regurgitant volume ( 66% ) and effective regurgitant orifice area ( 76% ) 5 (2–4) Direct mitral valve annuloplasty (ventriculoplasty) AccuCinch Moderate to severe FMR, NYHA class II–IV, LVEF ≥ 20% Safety and efficacy trials ( NCT00800046, NCT01899573, NCT02806570, NCT02153892, NCT03183895 ) Recruiting 30-day device-related or procedure-related MAE, MACE, acute and 30-day MR reduction 197 (?) 6MWT , 6-min walk test; BCM , bioabsorbable cardiac matrix; FMR , functional mitral regurgitation; HF , heart failure; LV , left ventricle; LVEF , left ventricular ejection fraction; LVEDVi , left ventricular end-diastolic volume indexed to body surface area; LVESVi , left ventricular end-systolic volume indexed to BSA; MACCE , major adverse cardiac cerebral events; MACE , major adverse cardiac events; MAE , major adverse events; MI , myocardial infarction; MR, mitral regurgitation; No.…”

Computational analysis of the electromechanical performance of mitral valve cerclage annuloplasty using a patient-specific ventricular model

“…Patients treated by this tightening procedure benefit from the stress unloading effect in their ventricular muscles, which ultimately reduces the size of the ventricles. Successful MVCA cases in swine, canine and human were reported previously [234]. However, the clinical outcomes of the MVCA procedure were not satisfactory for some patients [234].…”