Evaluating Mitral TEER in the Management of Moderate Secondary Mitral Regurgitation Among Heart Failure Patients.

BACKGROUND: Moderate secondary mitral regurgitation (SMR) represents a subgroup of heart failure (HF) patients with treatment restricted to medical therapy. Outcomes in patients with moderate SMR treated with mitral transcatheter edge-to-edge repair (M-TEER) are less well known. OBJECTIVES: The aim of this study was to assess the safety and effectiveness of M-TEER in subjects with moderate SMR using the EXPANDed studies. METHODS: One-year outcomes in subjects from the EXPANDed studies (EXPAND [A Contemporary, Prospective Study Evaluating Real-world Experience of Performance and Safety for the Next Generation of MitraClip Devices] and EXPAND G4 [A Post-Market Study Assessment of the Safety and Performance of the MitraClip G4 System] MitraClip studies) with baseline moderate SMR (2+), per echocardiographic core laboratory (ECL) assessment, were compared with subjects with baseline severe SMR (≥3+). RESULTS: There were 335 subjects with moderate SMR and 525 with severe SMR at baseline per ECL review. Baseline characteristics were similar between the 2 subgroups. After treatment with M-TEER, significant MR reduction was achieved in both groups. Significant left ventricular (LV) reverse remodeling was observed through 1 year, with a >20 mL decrease in LV end-diastolic and end-systolic volumes on average in the moderate SMR group. Significant 1-year improvements in NYHA functional class (>78% NYHA functional class I or II) and quality of life (>20 points on the Kansas City Cardiomyopathy Questionnaire-Overall Summary) were observed in subjects with moderate SMR. Similarly, low rates of major adverse events, all-cause mortality, and HF hospitalizations were observed between the 2 subgroups through 1 year. CONCLUSIONS: In the EXPANDed studies, subjects with moderate SMR treated with M-TEER had improvements similar to subjects with severe SMR in quality of life and positive LV remodeling at 1 year. Future studies are needed to evaluate if M-TEER would be beneficial for HF patients with moderate SMR.

Mortality Associated With Proportionality of Secondary Mitral Regurgitation After Transcatheter Mitral Valve Repair: North American Mitraclip for Functional Mitral Regurgitation Registry.

The association, if any, between the effective regurgitant orifice area (EROA) to left ventricular end-diastolic volume (LVEDV) ratio and 1-year mortality is controversial in patients who undergo mitral transcatheter edge-to-edge repair (m-TEER) with the MitraClip system (Abbott Vascular, Santa Clara, CA). This study's objective was to determine the association between EROA/LVEDV and 1-year mortality in patients who undergo m-TEER with MitraClip. In patients with severe secondary (functional) mitral regurgitation (MR), we analyzed registry data from 11 centers using generalized linear models with the generalized estimating equations approach. We studied 525 patients with secondary MR who underwent m-TEER. Most patients were male (63%) and were New York Heart Association class III (61%) or IV (21%). Mitral regurgitation was caused by ischemic cardiomyopathy in 51% of patients. EROA/LVEDV values varied widely, with median = 0.19 mm2/ml, interquartile range [0.12,0.28] mm2/ml, and 187 patients (36%) had values <0.15 mm2/ml. Postprocedural mitral regurgitation severity was substantially alleviated, being 1+ or less in 74%, 2+ in 20%, 3+ in 4%, and 4+ in 2%; 1-year mortality was 22%. After adjustment for confounders, the logarithmic transformation (Ln) of EROA/LVEDV was associated with 1-year mortality (odds ratio 0.600, 95% confidence interval 0.386 to 0.933, p = 0.023). A higher Society of Thoracic Surgeons risk score was also associated with increased mortality. In conclusion, lower values of Ln(EROA/LVEDV) were associated with increased 1-year mortality in this multicenter registry. The slope of the association is steep at low values but gradually flattens as Ln(EROA/LVEDV) increases.

1-Year Outcomes With Fourth-Generation Mitral Valve Transcatheter Edge-to-Edge Repair From the EXPAND G4 Study.

BACKGROUND: The fourth-generation mitral transcatheter edge-to-edge repair (M-TEER) device introduced an improved clip deployment sequence, independent leaflet grasping, and 2 wider clip sizes to tailor the treatment of patients with mitral regurgitation (MR) for a broad range of anatomies. The 30-day safety and effectiveness of the fourth-generation M-TEER device were previously demonstrated. OBJECTIVES: The aim of this study was to evaluate 1-year outcomes in a contemporary, real-world cohort of subjects treated with the MitraClip G4 system. METHODS: EXPAND G4 is an ongoing prospective, multicenter, international, single-arm study that enrolled subjects with primary and secondary MR. One-year outcomes included MR severity (echocardiographic core laboratory assessed), heart failure hospitalization, all-cause mortality, functional capacity (NYHA functional class), and quality of life (Kansas City Cardiomyopathy Questionnaire). RESULTS: A total of 1,164 subjects underwent M-TEER from 2020 to 2022. At 1 year, there was a durable reduction in MR to mild or less in 92.6% and to none or trace in 44.2% (P < 0.0001 vs baseline). Few subjects had major adverse events through 1 year (<2% for myocardial infarction, surgical reintervention, or single-leaflet device attachment). The 1-year Kaplan-Meier estimates for all-cause mortality and heart failure hospitalization were 12.3% and 16.9%. Significant improvements in functional capacity (NYHA functional class I or II in 82%; P < 0.0001 vs baseline) and quality of life (18.5-point Kansas City Cardiomyopathy Questionnaire overall summary score improvement; P < 0.0001) were observed. CONCLUSIONS: M-TEER with the fourth-generation M-TEER device was safe and effective at 1 year, with durable reductions in MR severity to ≤1+ in more than 90% of patients and concomitant improvements in functional status and quality of life.