Contemporary Transcatheter Mitral Valve Replacement for Mitral Annular Calcification or Ring

ObjectivesThe aim of this study was to evaluate outcomes of commercial transcatheter mitral valve replacement (TMVR) for annular rings and calcification using contemporary techniques.BackgroundTMVR is evolving in the absence of other viable treatment options for severe mitral annular calcification and failing ring repairs. The concomitant use of laceration of the anterior mitral valve leaflet to prevent left ventricular outflow tract obstruction and pre-emptive alcohol septal ablation is not well studied in clinical practice.MethodsA single-center study was conducted of valve–in–mitral annular calcification (ViMAC) and valve-in-ring (ViRing) TMVR from September 2015 to April 2020. In-hospital and 30-day outcomes were assessed.ResultsForty patients underwent TMVR (28 ViMAC and 12 ViRing). Sixteen ViMAC (57%) and 5 ViRing (42%) patients underwent attempted laceration of the anterior mitral valve leaflet to prevent left ventricular outflow tract obstruction. Three patients underwent pre-emptive alcohol septal ablation. The median index hospitalization was 7 days. Six patients died within 30 days of the procedure, 6 (21%) in the ViMAC group and none in the ViRing group. Five patients (13%) had left ventricular outflow tract obstruction: 4 (14%) in the ViMAC cohort and 1 (8%) in the ViRing cohort. Five patients (13%) had either intraprocedural valve embolization or late migration (4 ViMAC and 1 ViRing). Technical success defined according to Mitral Valve Academic Research Consortium criteria was present in 25 patients (63%): 9 (75%) in the ViRing cohort and 16 (57%) in the ViMAC cohort. At 30 days, the mitral valve gradient was significantly reduced (5.5 ± 2.1 vs. 10.6 ± 4.8; p < 0.01). Three patients (8%) had at least moderate residual mitral regurgitation.ConclusionsTranscatheter ViMAC and ViRing can be successfully performed but frequently require the use of contemporary adjunctive techniques.     

Imaging for Native Mitral Valve Surgical and Transcatheter Interventions

There has been rapid progress in transcatheter therapies for mitral regurgitation. These developments have elevated the need for the imager to have a core understanding of the functional mitral valve anatomy. Pre- and intraoperative echocardiography for surgical mitral valve repair for mitral regurgitation has defined contemporary interventional imaging in many ways. The central tenets of these principles apply to interventional imaging of transcatheter mitral valve interventions. However, the heightened emphasis on procedural planning and procedural imaging is one of the new challenges posed by transcatheter interventions. This need for accurate and reliable information has required the imager to be agnostic to the imaging modality. Cardiac computed tomography has become critical in procedural planning in this new paradigm. The expanded use of pre-procedural cardiac magnetic resonance to quantify mitral regurgitation and characterize the left ventricle is another illustration of this newer approach. Other illustrations of the new world of interventional imaging include the expanded use of 3-dimensional (3D) transesophageal echocardiography and real-time fusion of echocardiography and fluoroscopy images. Imaging data are also the basis for computational modeling, 3D printing, and artificial intelligence. These technologies are being increasingly explored to improve therapy selection and prediction of procedural outcomes. This review provides an update of the essentials in present interventional imaging for surgical and transcatheter interventions for mitral regurgitation.     

Randomized Trials Are Needed for Transcatheter Mitral Valve Replacement

Transcatheter mitral valve replacement (TMVR) is a new therapy for treating symptomatic mitral regurgitation (MR) and stenosis. The proposed benefit of TMVR is the predictable, complete elimination of MR, which is less certain with transcatheter repair technologies such as TEER (transcatheter edge-to-edge repair). The potential benefit of MR elimination with TMVR needs to be rigorously evaluated against its risks which include relative procedural invasiveness, need for anticoagulation, and chronic structural valve deterioration. Randomized controlled trials (RCTs) are a powerful method for evaluating the safety and effectiveness of TMVR against current standard of care transcatheter therapies, such as TEER. RCTs not only help with the assessment of benefits and risks, but also with policies for determining operator or institutional requirements, resource utilization, and reimbursement. In this paper, the authors provide recommendations and considerations for designing pivotal RCTs for first-in-class TMVR devices.     

Transcatheter Mitral Valve Replacement: An Update on Current Techniques,Technologies, and Future Directions

Growing clinical data support the use of transcatheter therapies for significant mitral valve disease. Currently, edge-to-edge repair is the transcatheter treatment of choice, but many anatomies are not suitable. Transcatheter mitral valve replacement offers several potential advantages over transcatheter repair, most notably a greater and more sustained reduction in mitral regurgitation post-implantation, but also potential disadvantages. To enable the successful treatment of mitral valve disease in a wide range of patients and anatomies, we require an armory of transcatheter devices, including transcatheter mitral valve replacement systems.     

Tip-to-Base LAMPOON for Transcatheter Mitral Valve Replacement With a Protected Mitral Annulus

ObjectivesThe purpose of this study was to evaluate tip-to-base intentional laceration of the anterior mitral leaflet to prevent left ventricular outflow tract obstruction (LAMPOON) in patients undergoing transcatheter mitral valve replacement (TMVR) in annuloplasty rings or surgical mitral valves.BackgroundLAMPOON is an effective adjunct to TMVR that prevents left ventricular outflow tract obstruction (LVOTO). Laceration is typically performed from the base to the tip of the anterior mitral leaflet. A modified laceration technique from leaflet tip to base may be effective in patients with a prosthesis that protects the aortomitral curtain.MethodsThis is a multicenter, 21-patient, consecutive retrospective observational cohort. Patients underwent tip-to-base LAMPOON to prevent LVOTO and leaflet overhang, or therapeutically to lacerate a long anterior mitral leaflet risking or causing LVOTO. Outcomes were compared with findings from patients in the LAMPOON investigational device exemption trial with a prior mitral annuloplasty.ResultsTwenty-one patients with a annuloplasty or valve prosthesis–protected mitral annulus underwent tip-to-base LAMPOON (19 preventive, 2 rescue). Leaflet laceration was successful in all and successfully prevented or treated LVOTO in all patients. No patients had significant LVOTO upon discharge. There were 2 cases of unintentional aortic valve injury (1 patient underwent emergency transcatheter aortic valve replacement and 1 patient underwent urgent surgical aortic valve replacement). In both cases, the patients had a supra-annular ring annuloplasty, and the retrograde aortic guiding catheter failed to insulate the guidewire lacerating surface from the aortic root. All patients survived to 30 days. Compared with classic retrograde LAMPOON, there was a trend toward shorter procedure time.ConclusionsTip-to-base laceration is a simple, effective, and safe LAMPOON variant applicable to patients with an appropriately positioned mitral annular ring or bioprosthetic valve. Operators should take care to insulate the lacerating surface from adjacent structures.     

Neo-LVOT and Transcatheter Mitral Valve Replacement: Expert Recommendations

With the advent of transcatheter mitral valve replacement (TMVR), the concept of the neo–left ventricular outflow tract (LVOT) was introduced and remains an essential component of treatment planning. This paper describes the LVOT anatomy and provides a step-by-step computed tomography methodology to segment and measure the neo-LVOT while discussing the current evidence and outstanding challenges. It also discusses the technical and hemodynamic factors that play a major role in assessing the neo-LVOT. A summary of expert-based recommendations about the overall risk of LVOT obstruction in different scenarios is presented along with the currently available methods to reduce the risk of LVOT obstruction and other post-procedural complications.     

Transcatheter Mitral Valve Replacement With the Transseptal EVOQUE System

ObjectivesThe aim of this study was to examine the initial experience with a novel transseptal transcatheter mitral valve replacement (TMVR) system.BackgroundTransseptal TMVR may offer a less invasive option than surgery for mitral regurgitation (MR) with greater efficacy and fewer anatomic limitations than transcatheter repair.MethodsPatients were treated with the EVOQUE TMVR system from September 2018 to October 2019. Key inclusion criteria were moderate or greater MR, New York Heart Association functional class ≥II, and high or prohibitive surgical risk. The primary outcome was technical success, defined by Mitral Valve Academic Research Consortium criteria.ResultsFourteen patients were treated, all with at least moderate to severe MR. The median age was 84 years, and the median Society of Thoracic Surgeons score was 4.6%. MR was degenerative in 4 (28.6%), functional in 3 (21.4%), and mixed in 7 (50%). Technical success was achieved in 13 patients (92.9%), and 1 patient was converted to surgery. At 30 days there was 1 noncardiovascular mortality (7.1%), 2 strokes (14.3%), no myocardial infarctions, and no rehospitalizations. Two patients (14.3%) underwent paravalvular leak closure. One patient (7.1%) underwent alcohol septal ablation for left ventricular outflow tract obstruction. Including the 2 patients with paravalvular leak closure, MR was mild or less in all implanted patients at 30 days, with no MR in 10 (83.3%). Mean mitral gradient was 5.8 mm Hg (median). New York Heart Association functional class improved to ≤II in 9 patients (81.8%).ConclusionsThis first-in-human experience has demonstrated the feasibility of the transseptal EVOQUE TMVR system. Further clinical studies are required to establish safety and clinical outcomes.     

Transcatheter Mitral Valve Repair in Cardiogenic Shock and Mitral Regurgitation: A Patient-Level,Multicenter Analysis

ObjectivesThe aim of this study was to evaluate the outcome of transcatheter mitral valve repair (TMVr) in patients with cardiogenic shock and significant mitral regurgitation (MR).BackgroundPatients in cardiogenic shock with severe MR have a poor prognosis in the setting of conventional medical therapy. Because of its favorable safety profile, TMVr is being increasingly used as an acute therapy in this population, though its efficacy remains unknown.MethodsA multicenter, collaborative, patient-level analysis was conducted. Patients with cardiogenic shock and moderate to severe (3+) or severe (4+) MR who were not surgical candidates were treated with TMVr. The primary outcome was in-hospital mortality. Secondary outcomes included 90-day mortality, heart failure (HF) hospitalization, and the combined event rate of 90-day mortality and HF hospitalization following dichotomization by TMVr device success.ResultsBetween January 2011 and February 2019, 141 patients across 14 institutions met the inclusion criteria. In-hospital mortality occurred in 22 patients (15.6%), at 90 days in 38 patients (29.5%), and at one year in 55 patients (42.6%). Median length of hospital stay following TMVr was 10 days (interquartile range: 6 to 20 days). HF hospitalization occurred in 26 patients (18.4%) at a median of 73 days (interquartile range: 26 to 546 days). When stratified by TMVr procedural results, successful TMVr reduced rates of in-hospital mortality (hazard ratio [HR]: 0.36; 95% confidence interval [CI]: 0.13 to 0.98; p = 0.04), 90-day mortality (HR: 0.36; 95% CI: 0.16 to 0.78; p = 0.01), and the composite of 90-day mortality and HF hospitalization (HR: 0.41; 95% CI: 0.19 to 0.90; p = 0.03).ConclusionsTMVr may improve short- and intermediate-term mortality in high-risk patients with cardiogenic shock and moderate to severe MR. Randomized studies are needed to definitively establish MR as a therapeutic target in patients with cardiogenic shock.     

Impact of Transcatheter Mitral Valve Repair on Preprocedural and Postprocedural Hospitalization Rates

ObjectivesThe objective of this study was to determine the effect of transcatheter mitral valve repair (TMVr) on hospitalization rates by assessing pre- and postprocedural hospitalization patterns.BackgroundTMVr has emerged as the treatment of choice for selected patients with mitral regurgitation, but the impact of these procedures on hospital utilization remains unclear.MethodsAll patients who underwent TMVr in Ontario, Canada, between 2011 and 2017 were included in this observational study using population-based data. Hospitalization person-year rates were assessed in the years before and after TMVr and 4 predefined intervals: 1 to 30, 31 to 90, 91 to 182, and 183 to 365 days. Main outcomes of interest were all-cause and heart failure (HF) hospitalizations. Poisson regression models were used to compare incidence rates across all time periods.ResultsThe study cohort included 523 patients. In the year preceding TMVr, 66.2% of patients were hospitalized compared with 47.4% in the year following. There were stepwise increases in both all-cause and HF hospitalization rates in the periods preceding the index procedure, and all postprocedural periods had significantly lower hospitalization rates. The adjusted rate ratios for all-cause and HF-related hospitalization in the year after TMVr were 0.65 (95% CI: 0.56-0.76) and 0.38 (95% CI: 0.29-0.51), respectively. All time periods had significant reductions in all-cause and HF hospitalization in the adjusted analysis.ConclusionsIn this population-based study, significant reductions were observed in both all-cause and HF-related hospitalizations in all time periods after TMVr compared with the year prior. This suggests that TMVr has a sustained effect on hospitalization rates despite a high-risk population.     

Transcatheter Aortic Valve Replacement in Failed Transcatheter Bioprosthetic Valves

Transcatheter aortic valve replacement (TAVR) is increasingly being performed in younger and lower surgical risk patients. Given the longer life expectancy of these patients, the bioprosthetic valve will eventually fail, and aortic valve reintervention may be necessary. Although currently rare, redo-TAVR will likely increase in the future as younger patients are expected to outlive their transcatheter bioprosthesis. This review provides a contemporary overview of the indications, procedural planning, implantation technique, and outcomes of TAVR in failed transcatheter bioprosthetic aortic valves.     

Multiphase Assessment of Mitral Annular Dynamics in Consecutive Patients With Significant Mitral Valve Disease

ObjectivesThe aim of this study was to clarify the dynamics of the mitral annulus throughout the cardiac cycle and its relevance to transcatheter mitral valve replacement (TMVR) sizing and case selection.BackgroundLimited data are available regarding the relevance of mitral annular (MA) and neo–left ventricular outflow tract (LVOT) dynamics in the overall population presenting with significant mitral valve disease.MethodsPatients attending a combined surgical-transcatheter heart valve clinic for severe symptomatic mitral valve disease were assessed using multiphase computed tomography. The relative influence of MA and neo-LVOT dynamics to TMVR case selection was studied.ResultsA total of 476 patients with significant mitral valve disease were evaluated. In 99 consecutive patients with severe mitral regurgitation, a 10-phase assessment showed that the mitral annulus was on average largest in late systole. On comparing maximal MA dimension with late systolic dimension, TMVR size assignment changed in 24.2% of patients. If the average MA perimeter was used to determine sizing, 48.5% were excluded because of MA dimension being too large; in a multiphase assessment of the neo-LVOT, an additional 16.2% were excluded on the basis of neo-LVOT dimension. In an expanded series of 312 consecutive patients, selection protocol influenced anatomical exclusion: a manufacturer-proposed early systolic approach excluded 69.2% of patients, whereas a late systolic approach excluded 82.7% of patients, the vast majority because of large mitral annuli.ConclusionsContemporary TMVR can treat only a minority of patients with severe mitral regurgitation, principally because of limitations of large MA dimension.     

German Multicenter Experience With a New Leaflet-Based Transcatheter Mitral Valve Repair System for Mitral Regurgitation

ObjectivesThe aim of this study was to investigate the procedural and short-term safety and efficacy of a new leaflet-based transcatheter mitral valve repair system.BackgroundThe PASCAL repair system has been recently approved for percutaneous treatment of mitral regurgitation (MR). Novel characteristics are broad paddles positioned around a central spacer and the ability for independent leaflet capture.MethodsProcedural and 30-day outcomes were investigated in the first 309 patients with symptomatic MR 3+/4+ treated with the PASCAL repair system at 10 sites. Primary efficacy endpoints were technical success and degree of residual MR at discharge. The primary safety endpoint was the rate of major adverse events (MAE).ResultsAmong the 309 patients (mean age 77 ± 10 years, 42% women, mean European System for Cardiac Operative Risk Evaluation II score 5.8 ± 4.5%) included in this study, MR etiology was degenerative in 33%, functional in 52%, and mixed in 16%. Eighty-six percent of patients were in New York Heart Association functional class III or IV. The technical success rate was 96%. Of 308 patients discharged alive, MR was ≤2+ in 93.5%. At 30 days, the MAE rate was 4.1%, with an estimated all-cause mortality rate of 2.0%, and 72% of patients were in New York Heart Association functional class ≤II (p < 0.001). Rates of device success and CLASP (Edwards PASCAL Transcatheter Mitral Valve Repair System Study) trial–defined clinical success were 81.9% and 86.9%, respectively. Single-leaflet device attachment occurred in 7 patients (2.3%).ConclusionsMitral valve repair with the PASCAL system in the early post-approval phase was effective and safe, with high procedural success rates and low rates of MAE. MR was significantly reduced, accompanied by significant improvement in functional status.     

Current Status and Future Prospects of Transcatheter Mitral Valve Replacement: JACC State-of-the-Art Review

Mitral regurgitation (MR) is the most prevalent valvular heart disease and, when left untreated, it confers a poorer prognosis. Catheter-based repair therapies face some limitations like their applicability on challenging anatomies and the potential recurrence of significant MR over time. Transcatheter mitral valve replacement (TMVR) has emerged as a less invasive approach potentially overcoming some of the current limitations associated with transcatheter mitral valve repair. Several devices are under clinical investigation, and a growing number of systems allow for a fully percutaneous transfemoral approach. In this review, the authors aimed to delineate the main challenges faced by the TMVR field, to highlight the key aspects for procedural planning, and to describe the clinical results of the TMVR systems under clinical investigation. Finally, they also discuss what the future perspectives are for this emerging field.     

Valve Strain Quantitation in Normal Mitral Valves and Mitral Prolapse With Variable Degrees of Regurgitation

ObjectivesThe aim of this study was to quantitate patient-specific mitral valve (MV) strain in normal valves and in patients with mitral valve prolapse with and without significant mitral regurgitation (MR) and assess the determinants of MV strain.BackgroundFew data exist on MV deformation during systole in humans. Three-dimensional echocardiography allows for dynamic MV imaging, enabling digital modeling of MV function in health and disease.MethodsThree-dimensional transesophageal echocardiography was performed in 82 patients, 32 with normal MV and 50 with mitral valve prolapse (MVP): 12 with mild mitral regurgitation or less (MVP ? MR) and 38 with moderate MR or greater (MVP + MR). Three-dimensional MV models were generated, and the peak systolic strain of MV leaflets was computed on proprietary software.ResultsLeft ventricular ejection fraction was normal in all groups. MV annular dimensions were largest in MVP + MR (annular area: 13.8 ± 0.7 cm²) and comparable in MVP ? MR (10.6 ± 1 cm²) and normal valves (10.5 ± 0.3 cm²; analysis of variance: p < 0.001). Similarly, MV leaflet areas were largest in MVP + MR, particularly the posterior leaflet (8.7 ± 0.5 cm²); intermediate in MVP ? MR (6.5 ± 0.7 cm²); and smallest in normal valves (5.5 ± 0.2 cm²; p < 0.0001). Strain was overall highest in MVP + MR and lowest in normal valves. Patients with MVP ? MR had intermediate strain values that were higher than normal valves in the posterior leaflet (p = 0.001). On multivariable analysis, after adjustment for clinical and MV geometric parameters, leaflet thickness was the only parameter that was retained as being significantly correlated with mean MV strain (r = 0.34; p = 0.008).ConclusionsMVs that exhibit prolapse have higher strain compared to normal valves, particularly in the posterior leaflet. Although higher strain is observed with worsening MR and larger valves and annuli, mitral valve leaflet thickness—and, thus, underlying MV pathology—is the most significant independent determinant of valve deformation. Future studies are needed to assess the impact of MV strain determination on clinical outcome.     

Impact of Proportionality of Secondary Mitral Regurgitation on Outcome After Transcatheter Mitral Valve Repair

ObjectivesThe purpose of this paper was to evaluate the impact of proportionality of secondary mitral regurgitation (SMR) in a large real-world registry of transcatheter edge-to-edge mitral valve repair (TMVr)BackgroundDifferences in the outcomes of recent randomized trials of TMVr for SMR may be explained by the proportionality of SMR severity to left ventricular (LV) volume.MethodsThe ratio of pre-procedural effective regurgitant orifice area (EROA) to LV end-diastolic volume (LVEDV) was retrospectively assessed in patients undergoing TMVr for severe SMR between 2008 and 2019 from the EuroSMR registry. A recently proposed SMR proportionality scheme was adapted to stratify patients according to EROA/LVEDV ratio in 3 groups: MR-dominant (MD), MR-LV-co-dominant (MLCD), and LV-dominant (LD). All-cause mortality was assessed as a primary outcome, secondary heart failure (HF) outcomes included hospitalization for HF (HHF), New York Heart Association (NYHA) functional class, N-terminal pro–B-type natriuretic peptide (NT-proBNP), 6-min-walk distance, quality of life and MR grade.ResultsA total of 1,016 patients with an EROA/LVEDV ratio were followed for 22 months after TMVr. MR was reduced to grade ≤2+ in 92%, 96%, and 94% of patients (for MD, MLCD, and LD, respectively; p = 0.18). After adjustment for covariates including age, sex, diabetes, kidney function, body surface area, LV ejection fraction, and procedural MR reduction (grade ≤2+), adjusted rates of 2-year mortality in MD patients did not differ from those for MLCD patients (17% vs. 18%, respectively), whereas it was higher in LD patients (23%; p = 0.02 for comparison vs. MD+MLCD). The adjusted first HHF rate differed between groups (44% in MD, 56% in MLCD, 29% in LD; p = 0.01) as did the adjusted time for first death or HHF rate (66% in MD, 82% in MLCD, 68% in LD; p = 0.02). Improvement of NYHA functional class was seen in all groups (p < 0.001). Values for 6-min-walk distances, quality of life and NT-proBNP improved in most patients.ConclusionsMD and MLCD patients had a comparable, adjusted 2-year mortality rate after TMVr which was slightly better than that of LD patients. Patients treated with TMVr had symptomatic improvement regardless of EROA/LVEDV ratio.     

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

BackgroundThe impact of transcatheter edge-to-edge repair (TEER) on national surgical mitral valve repair (MVr) volume and outcomes is unknown.ObjectivesThis study aims to assess the impact of TEER availability on MVr volumes and outcomes for degenerative mitral regurgitation.MethodsMVr 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.ResultsFrom 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.ConclusionsThe 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.     

Role of Cardiac CT in Pre-Procedure Planning for Transcatheter Mitral Valve Replacement

ObjectivesThis study sought to evaluate cardiac computed tomography (CCT) findings and their clinical impact among patients being considered for transcatheter mitral valve replacement (TMVR).BackgroundCCT is used to evaluate whether patients are candidates for TMVR, but limited data exist on the yield of such tests.MethodsPatients referred for pre-procedural CCT for TMVR planning in the context of failing mitral bioprosthetic valves, annuloplasty rings, and severe native valve disease with annular calcification were included in this study. CCT findings were analyzed to evaluate for suitability for TMVR. In the subset of patients who underwent TMVR, echocardiographic and procedural characteristics were recorded.ResultsAmong 80 patients who underwent pre-procedural CCT, the mean age was 71.8 ± 11.4 years, 60% were women, and the mean Society of Thoracic Surgeon score was 9.4 ± 6.7. Most cases were referred for valve-in-native annular calcification planning (n = 43), followed by valve-in-valve (n = 29), and valve-in-ring procedures (n = 8). A total of 51 (64%) patients did not undergo TMVR, 37 of whom had high-risk features identified on CCT. The most common reason for exclusion was related to large annular size, followed by heightened risk of left ventricular outflow tract (LVOT) obstruction. Among 29 patients (36%) who underwent TMVR, the 30-day mortality rate was 17%. Five patients experienced LVOT obstruction, 4 of whom were predicted by CCT. Following TMVR, 5 patients had at least moderate peri-valvular regurgitation.ConclusionsA minority of patients referred for TMVR planning ultimately undergo the procedure. CCT identifies unsuitable anatomy and leads to exclusion in a significant number of cases.     

Mitral Valve Remodeling and Strain in Secondary Mitral Regurgitation: Comparison With Primary Regurgitation and Normal Valves

ObjectivesThe aim of this study was to assess mitral valve (MV) remodeling and strain in patients with secondary mitral regurgitation (SMR) compared with primary MR (PMR) and normal valves.BackgroundA paucity of data exists on MV strain during the cardiac cycle in humans. Real-time 3-dimensional (3D) echocardiography allows for dynamic MV imaging, enabling computerized modeling of MV function in normal and disease states.MethodsThree-dimensional transesophageal echocardiography (TEE) was performed in a total of 106 subjects: 36 with SMR, 38 with PMR, and 32 with normal valves; MR severity was at least moderate in both MR groups. Valve geometric parameters were quantitated and patient-specific 3D MV models generated in systole using a dedicated software. Global and regional peak systolic MV strain was computed using a proprietary software.ResultsMV annular area was larger in both the SMR and PMR groups (12.7 ± 0.7 and 13.3 ± 0.7 cm², respectively) compared with normal subjects (9.9 ± 0.3 cm²; p < 0.05). The leaflets also had significant remodeling, with total MV leaflet area larger in both SMR (16.2 ± 0.9 cm²) and PMR (15.6 ± 0.8 cm²) versus normal subjects (11.6 ± 0.4 cm²). Leaflets in SMR were thicker than those in normal subjects but slightly less than those with PMR posteriorly. Posterior leaflet strain was significantly higher than anterior leaflet strain in all 3 groups. Despite MV remodeling, strain in SMR (8.8 ± 0.3%) was overall similar to normal subjects (8.5 ± 0.2%), and both were lower than in PMR (12 ± 0.4%; p < 0.0001). Valve thickness, severity of MR, and primary etiology of MR were correlates of strain, with leaflet thickness being the multivariable parameter significantly associated with MV strain. In patients with less severe MR, anterior leaflet strain in SMR was lower than normal, whereas strain in PMR remained higher than normal.ConclusionsThe MV in secondary MR remodels significantly and similarly to PMR with a resultant larger annular area, leaflet surface area, and leaflet thickness compared with that of normal subjects. Despite these changes, MV strain remains close to or in some instances lower than normal and is significantly lower than that of PMR. Strain determination has the potential to improve characterization of MV mechano-biologic properties in humans and to evaluate its prognostic impact in patients with MR, with or without valve interventions.     

Repeat Transcatheter Aortic Valve Replacement for Transcatheter Prosthesis Dysfunction

BackgroundTranscatheter aortic valve replacement (TAVR) use is increasing in patients with longer life expectancy, yet robust data on the durability of transcatheter heart valves (THVs) are limited. Redo-TAVR may play a key strategy in treating patients in whom THVs fail.ObjectivesThe authors sought to examine outcomes following redo-TAVR.MethodsThe Redo-TAVR registry collected data on consecutive patients who underwent redo-TAVR at 37 centers. Patients were classified as probable TAVR failure or probable THV failure if they presented within or beyond 1 year of their index TAVR, respectively.ResultsAmong 63,876 TAVR procedures, 212 consecutive redo-TAVR procedures were identified (0.33%): 74 within and 138 beyond 1 year of the initial procedure. For these 2 groups, TAVR-to-redo-TAVR time was 68 (38 to 154) days and 5 (3 to 6) years. The indication for redo-TAVR was THV stenosis in 12 (16.2%) and 51 (37.0%) (p = 0.002) and regurgitation or combined stenosis–regurgitation in 62 (83.8%) and 86 (62.3%) (p = 0.028), respectively. Device success using VARC-2 criteria was achieved in 180 patients (85.1%); most failures were attributable to high residual gradients (14.1%) or regurgitation (8.9%). At 30-day and 1-year follow-up, residual gradients were 12.6 ± 7.5 mm Hg and 12.9 ± 9.0 mm Hg; valve area 1.63 ± 0.61 cm² and 1.51 ± 0.57 cm²; and regurgitation ≤mild in 91% and 91%, respectively. Peri-procedural complication rates were low (3 stroke [1.4%], 7 valve malposition [3.3%], 2 coronary obstruction [0.9%], 20 new permanent pacemaker [9.6%], no mortality), and symptomatic improvement was substantial. Survival at 30 days was 94.6% and 98.5% (p = 0.101) and 83.6% and 88.3% (p = 0.335) at 1 year for patients presenting with early and late valve dysfunction, respectively.ConclusionsRedo-TAVR is a relatively safe and effective option for selected patients with valve dysfunction after TAVR. These results are important for applicability of TAVR in patients with long life expectancy in whom THV durability may be a concern.     

Transcatheter Edge-to-Edge Mitral Valve Repair With the MitraClip G4 System

ObjectivesThe primary objective of this study was to evaluate the effectiveness of the MitraClip G4 in the reduction of mitral regurgitation (MR).BackgroundThe next-generation MitraClip G4 system was recently introduced for the treatment of MR in the United States.MethodsThe study included consecutive patients undergoing transcatheter mitral edge-to-edge repair for MR with the MitraClip G4. The key outcome was the proportion of patients with MR reduction to ≤2+ at 30 days.ResultsFifty-nine patients (median age 77 years, 62.7% men) were treated with the MitraClip G4. Reduction of MR to ≤2+ was achieved in 57 patients (96.6%) during the procedure, 58 patients (98.3%) at discharge, and 57 patients (96.6%) by 30 days. The median number of MitraClips used per patient was 2 (interquartile range: 1 to 3). Wide clips (NTW/XTW) were used in 82.7% of patients. The XTW clip was used most frequently as the first clip in patients with degenerative MR (65.4%) and the NTW clip in those with secondary MR (72.7%). The independent grasping mechanism was used in 49.2% of patients.ConclusionsUse of the MitraClip G4 system was associated with excellent reduction in MR to ≤2+ in 96.6% of patients at 30 days. The availability of multiple MitraClip G4 sizes, especially the wide clips, and the ability to independently grasp leaflets are the likely contributors to MR reduction.