Impact of Transcatheter Mitral Valve Repair Availability on Volume and Outcomes of Surgical Repair.

BACKGROUND: The impact of transcatheter edge-to-edge repair (TEER) on national surgical mitral valve repair (MVr) volume and outcomes is unknown. OBJECTIVES: This study aims to assess the impact of TEER availability on MVr volumes and outcomes for degenerative mitral regurgitation. METHODS: MVr volume, 30-day and 5-year outcomes, including mortality, heart failure rehospitalization and mitral valve reintervention, were obtained from the Society of Thoracic Surgeons database linked with Medicare administrative claims and were compared within TEER centers before and after the first institutional TEER procedure. A difference-in-difference approach comparing parallel trends in coronary artery bypass grafting outcomes was used to account for temporal improvements in perioperative care. RESULTS: From July 2011 through December 2018, 13,959 patients underwent MVr at 278 institutions, which became TEER-capable during the study period. There was no significant change in median annualized institutional MVr volume before (32 [IQR: 17-54]) vs after (29 [IQR: 16-54]) the first TEER (P = 0.06). However, higher-risk (Society of Thoracic Surgeons predicted risk of mortality ≥2%) MVr procedures declined over the study period (P < 0.001 for trend). The introduction of TEER was associated with reduced risk-adjusted odds of mortality after MVr at 30 days (adjusted OR: 0.73; 95% CI: 0.54-0.99) and over 5 years (adjusted HR: 0.75; 95% CI: 0.66-0.86). These improvements in 30-day and 5-year mortality were significantly greater than equivalent trends in coronary artery bypass grafting. CONCLUSIONS: The introduction of TEER has not significantly changed overall MVr case volumes for degenerative mitral regurgitation but is associated with a decrease in higher-risk surgical operations and improved 30-day and 5-year outcomes within institutions adopting the technology.

Relationship between the magnitude of reduction in mitral regurgitation severity and left ventricular and left atrial reverse remodeling after MitraClip therapy.

BACKGROUND: MitraClip has been shown to reduce mitral regurgitation (MR) severity safely but to a lesser degree than surgery. No data exist on the magnitude of MR reduction necessary to reverse left ventricular (LV) and left atrial (LA) dilation in patients with severe MR. Therefore, an analysis was performed to evaluate the relationship between MR reduction and LV and LA volumes after MitraClip therapy. METHODS AND RESULTS: A total of 801 patients treated with MitraClip and 80 patients treated surgically were included. All patients had severe (3-4+) MR. MR severity, LV volumes at end-diastole and end-systole, and LA volumes were measured at baseline, discharge, 30 days, 6 months, and 1 year by an independent echocardiographic core laboratory. A linear repeated measures model was developed to determine the relationship between MR severity and time of measurement postindex procedure on longitudinal LV and LA volumes. Separate models were fit for functional MR and degenerative MR. In both degenerative and functional MR, reduction in LV volumes at end-diastole was associated with degree of residual MR at 12 months (P<0.0001). LV volumes at end-systole was significantly reduced in functional MR but not degenerative MR. LA volumes were significantly related to reduction of MR severity in both groups. CONCLUSIONS: Reduction of LV volumes at end-diastole and LA volumes, but not LV volumes at end-systole in degenerative MR, is consistent with correction of volume overload from primary MR. Reduction of all 3 measurements in functional MR demonstrates reverse remodeling when MR severity is reduced to either 1+ or 2+ by MitraClip therapy. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00209274.

Percutanenous therapies for mitral regurgitation.

Percutaneous therapies for the treatment of mitral regurgitation have emerged rapidly over the past several years. Most of the percutaneous approaches are modifications of existing surgical approaches to mitral annuloplasty or leaflet repair. Most of the percutaneous devices are based on surgical approaches. Catheter-based leaflet repair with the MitraClip is accomplished using an implantable clip to mimic the surgical edge-to-edge technique. Percutaneous annuloplasty can be achieved indirectly via the coronary sinus, or directly from retrograde left ventricular access. Several of these percutaneous approaches have been successfully used in trials or are in the early stages of use in practice.

Percutaneous repair or surgery for mitral regurgitation.

BACKGROUND: Mitral-valve repair can be accomplished with an investigational procedure that involves the percutaneous implantation of a clip that grasps and approximates the edges of the mitral leaflets at the origin of the regurgitant jet. METHODS: We randomly assigned 279 patients with moderately severe or severe (grade 3+ or 4+) mitral regurgitation in a 2:1 ratio to undergo either percutaneous repair or conventional surgery for repair or replacement of the mitral valve. The primary composite end point for efficacy was freedom from death, from surgery for mitral-valve dysfunction, and from grade 3+ or 4+ mitral regurgitation at 12 months. The primary safety end point was a composite of major adverse events within 30 days. RESULTS: At 12 months, the rates of the primary end point for efficacy were 55% in the percutaneous-repair group and 73% in the surgery group (P=0.007). The respective rates of the components of the primary end point were as follows: death, 6% in each group; surgery for mitral-valve dysfunction, 20% versus 2%; and grade 3+ or 4+ mitral regurgitation, 21% versus 20%. Major adverse events occurred in 15% of patients in the percutaneous-repair group and 48% of patients in the surgery group at 30 days (P<0.001). At 12 months, both groups had improved left ventricular size, New York Heart Association functional class, and quality-of-life measures, as compared with baseline. CONCLUSIONS: Although percutaneous repair was less effective at reducing mitral regurgitation than conventional surgery, the procedure was associated with superior safety and similar improvements in clinical outcomes. (Funded by Abbott Vascular; EVEREST II ClinicalTrials.gov number, NCT00209274.).