Tricuspid Regurgitation: From Imaging to Clinical Trials to Resolving the Unmet Need for Treatment.

Tricuspid regurgitation (TR) is a highly prevalent and heterogeneous valvular disease, independently associated with excess mortality and high morbidity in all clinical contexts. TR is profoundly undertreated by surgery and is often discovered late in patients presenting with right-sided heart failure. To address the issue of undertreatment and poor clinical outcomes without intervention, numerous structural tricuspid interventional devices have been and are in development, a challenging process due to the unique anatomic and physiological characteristics of the tricuspid valve, and warranting well-designed clinical trials. The path from routine practice TR detection to appropriate TR evaluation, to conduction of clinical trials, to enriched therapeutic possibilities for improving TR access to treatment and outcomes in routine practice is complex. Therefore, this paper summarizes the key points and methods crucial to TR detection, quantitation, categorization, risk-scoring, intervention-monitoring, and outcomes evaluation, particularly of right-sided function, and to clinical trial development and conduct, for both interventional and surgical groups.

Early Outcomes of 2 Mitral Valve Transcatheter Leaflet Approximation Devices: A Propensity Score-Matched Multicenter Comparison.

BACKGROUND: In addition to the edge-to-edge MitraClip repair system, the edge-to-spacer PASCAL repair system was approved for percutaneous treatment of severe mitral regurgitation (MR). Comparative data are lacking. OBJECTIVES: The aim of this study was to compare procedural and short-term safety and efficacy of 2 leaflet-based transcatheter mitral valve repair systems. METHODS: Procedural and 30-day outcomes were investigated in a propensity score-matched cohort of 307 PASCAL and 307 MitraClip patients at 10 sites. Matching criteria included sex, age, left ventricular ejection fraction, New York Heart Association functional class, MR etiology, left ventricular end-diastolic diameter, left atrial volume index, and vena contracta width. The 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). RESULTS: Technical success was 97.0% in the PASCAL group and 98.0% in the MitraClip group (P = 0.624). MR ≤2+ at discharge was comparable in both groups (PASCAL: 93.8% vs MitraClip: 92.4%; P = 0.527), with more patients exhibiting MR ≤1+ in the PASCAL group (70.5% vs 56.6%; P < 0.001). The postprocedural mean gradient was significantly higher in the MitraClip group (3.3 ± 1.5 mm Hg vs 3.9 ± 1.7 mm Hg; P < 0.001). At 30 days, all-cause mortality and MAE rates were similar (mortality: 1.7% vs 3.3%; P = 0.299; MAE: 3.9% vs 5.2%; P = 0.562). CONCLUSIONS: In this first large propensity score-matched comparison, procedural success rates and MAE did not differ significantly between patients treated with the PASCAL or MitraClip valve repair system. Procedural results with less than moderate MR and no elevated transmitral gradient were more common in the PASCAL group, which might have an impact on long-term outcome.

Indications, Limitations, and Development of Tricuspid Valve Interventions in Adults.

Tricuspid regurgitation is associated with excessive mortality and poor outcomes regardless of the cause and associated comorbidities. Despite this clear association with mortality, tricuspid valve diseases remain undertreated. Tricuspid valve surgery, either repair or replacement, has shown little detectable survival benefit. Transcatheter tricuspid valve interventions have emerged as a less invasive approach to tricuspid valve diseases. They can be categorised into coaptation devices, annuloplasty devices, transcatheter tricuspid valve replacement, heterotopic caval valve implantation, and tricuspid valve-in-valve. Despite the late referral and the patient's profile, results remain fairly acceptable at least in the short term, with good procedural device success, excellent safety profile, and sustained reduction of tricuspid regurgitation for up to 1 year. Because results are limited to the mid-term, transcatheter tricuspid valve intervention durability will need to be established before broader adoption of these technologies.

Outcomes Stratified by Adapted Inclusion Criteria After Mitral Edge-to-Edge Repair.

BACKGROUND: Although mitral valve transcatheter edge-to-edge repair (M-TEER) achieves symptomatic benefit for a broad spectrum of patients with relevant secondary mitral regurgitation, conflicting data exist on its prognostic impact. OBJECTIVES: Adapted enrollment criteria approaching those used in the COAPT (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients With Functional Mitral Regurgitation) and MITRA-FR (Percutaneous Repair or Medical Treatment for Secondary Mitral Regurgitation) trials were retrospectively applied to a European real-world registry to evaluate the influence of the respective criteria on outcomes. METHODS: A total of 1,022 patients included in the EuroSMR (European Registry of Transcatheter Repair for Secondary Mitral Regurgitation) registry and treated with M-TEER (November 2008 to September 2019) were stratified into COAPT-eligible (n = 353 [34.5%]) and COAPT-ineligible (n = 669 [65.5%]) as well as MITRA-FR-eligible (n = 408 [48.3%]) and MITRA-FR-ineligible (n = 437 [51.7%]) groups. RESULTS: Although the stratification of patients according to adapted MITRA-FR criteria led to comparable outcomes regarding all-cause mortality (P = 0.19), the application of adapted COAPT enrollment criteria demonstrated lower mortality rates in COAPT-eligible compared with COAPT-ineligible patients (P < 0.001). Multivariable Cox regression analysis identified New York Heart Association functional class IV (hazard ratio [HR]: 2.29; 95% confidence interval [CI]: 1.53-3.42; P < 0.001), logarithmic N-terminal pro-brain natriuretic peptide (HR: 1.47; 95% CI: 1.24-1.75; P < 0.001), and right ventricular-to-pulmonary arterial coupling (HR: 0.10; 95% CI: 0.02-0.57; P = 0.009) as independent predictors of outcome. Yet improvement of functional outcome was demonstrated in a subset of patients irrespective of COAPT eligibility status. CONCLUSIONS: In this real-world cohort of patients with secondary mitral regurgitation undergoing M-TEER, the retrospective application of adapted COAPT enrollment criteria successfully identified a specific phenotype demonstrating lower mortality rates. On the contrary, stratification according to adapted MITRA-FR criteria resulted in comparable outcomes.

Percutaneous Mitral Valve Annuloplasty in Patients With Secondary Mitral Regurgitation and Severe Left Ventricular Enlargement.

OBJECTIVES: This study sought to determine the effect of percutaneous mitral valve annuloplasty with the Carillon device versus guideline-directed medical therapy (GDMT) alone in patients with secondary mitral regurgitation (MR) and severe left ventricular (LV) enlargement. BACKGROUND: The clinical impact of the Carillon device in patients with severe LV dilation is not well established. METHODS: This is a pooled analysis involving 3 prospective trials (TITAN [Transcatheter Implantation of Carillon Mitral Annuloplasty Device], TITAN II, and REDUCE FMR [CARILLON Mitral Contour System for Reducing Functional Mitral Regurgitation] trials) in which patients with functional MR and severe LV enlargement (LV end-diastolic diameter >65 mm) were treated with GDMT and the Carillon device versus GDMT alone. Key outcomes of this analysis were changes over 1 year of follow-up in mitral valve and LV echocardiographic parameters, functional outcome, quality of life, mortality, and heart failure hospitalization (HFH). RESULTS: A total of 95 patients (67 in the Carillon group, 28 in the GDMT group) with severe LV enlargement were included. In the Carillon group, all mitral valve and LV morphology parameters were significantly improved at 1 year. Regurgitant volume decreased by 12 ml (p < 0.001), MR grade decreased by 0.6 U (p < 0.001), LV end-diastolic volume decreased by 25 cm3 (p = 0.005), and LV end-systolic volume decreased by 21 cm3 (p = 0.01). Significant functional improvement differences were also noted between the Carillon group and the GDMT group including an improvement of Kansas City Cardiomyopathy Questionnaire score (15 ± 4 vs. 6 ± 6; p = 0.03). The incidence of HFH was 29.9% versus 50.0% and the cumulative rate of HFH was 0.43 versus 0.75 (p < 0.001). CONCLUSIONS: In patients with functional MR and severe LV enlargement, the Carillon device improved mitral valve function, LV morphology, and functional outcome compared with patients receiving GDMT only. Preoperative LV dimension should not be a limiting factor when evaluating patient eligibility or anticipated response to therapy with the Carillon device.

Impact of Right Ventricular Dysfunction on Outcomes After Transcatheter Edge-to-Edge Repair for Secondary Mitral Regurgitation.

OBJECTIVES: This study sought to assess the impact of right ventricular dysfunction (RVD) as defined by impaired right ventricular-to-pulmonary artery (RV-PA) coupling, on survival after edge-to-edge transcatheter mitral valve repair (TMVR) for severe secondary mitral regurgitation (SMR). BACKGROUND: Conflicting data exist regarding the benefit of TMVR in severe SMR. A possible explanation could be differences in RVD. METHODS: Using data from the EuroSMR (European Registry on Outcomes in Secondary Mitral Regurgitation) registry, this study compared the characteristics and outcomes of SMR patients undergoing TMVR, according to their RV-PA coupling, assessed by tricuspid annular plane systolic excursion-to-systolic pulmonary artery pressure (TAPSE/sPAP) ratio. RESULTS: Overall, 817 patients with severe SMR and available RV-PA coupling assessment underwent TMVR in the participating centers. RVD was present in 211 patients (25.8% with a TAPSE/sPAP ratio <0.274 mm/mm Hg). Although all patients demonstrated significant improvement in their New York Heart Association (NYHA) functional class, there was a trend toward a lower rate of NYHA functional class I or II among patients with RVD (56.5% vs. 65.5%, respectively; p = 0.086) after TMVR. Survival rates at 1 and 2 years were lower among patients with RVD (70.2% vs. 84.0%, respectively; p < 0.001; and 53.4% vs. 73.1%, respectively; p < 0.001). On multivariate analysis, a reduced TAPSE/sPAP ratio was a strong predictor of mortality (odds ratio: 1.62; 95% confidence interval: 1.14 to 2.31; p = 0.007). CONCLUSIONS: RVD, as shown by impairment of RV-PA coupling, is a major predictor of adverse outcome in patients undergoing TMVR for severe SMR. The often neglected functional and anatomic RV parameters should be systematically assessed when planning TMVR procedures for patients with severe SMR.

Transcatheter Edge-to-Edge Repair for Treatment of Tricuspid Regurgitation.

BACKGROUND: Tricuspid regurgitation (TR) is a frequent disease with a progressive increase in mortality as disease severity increases. Transcatheter therapies for treatment of TR may offer a safe and effective alternative to surgery in this high-risk population. OBJECTIVES: The purpose of this report was to study the 1-year outcomes with the TriClip transcatheter tricuspid valve repair system, including repair durability, clinical benefit and safety. METHODS: The TRILUMINATE trial (n = 85) is an international, prospective, single arm, multicenter study investigating safety and performance of the TriClip Tricuspid Valve Repair System in patients with moderate or greater TR. Echocardiographic assessment was performed by a core laboratory. RESULTS: At 1 year, TR was reduced to moderate or less in 71% of subjects compared with 8% at baseline (p < 0.0001). Patients experienced significant clinical improvements in New York Heart Association (NYHA) functional class I/II (31% to 83%, p < 0.0001), 6-minute walk test (272.3 ± 15.6 to 303.2 ± 15.6 meters, p = 0.0023) and Kansas City Cardiomyopathy Questionnaire (KCCQ) score (improvement of 20 ± 2.61 points, p < 0.0001). Significant reverse right ventricular remodeling was observed in terms of size and function. The overall major adverse event rate and all-cause mortality were both 7.1% at 1 year. CONCLUSION: Transcatheter tricuspid valve repair using the TriClip device was found to be safe and effective in patients with moderate or greater TR. The repair itself was durable at reducing TR at 1 year and was associated with a sustained and marked clinical benefit with low mortality after 1 year in a fragile population that was at high surgical risk. (TRILUMINATE Study With Abbott Transcatheter Clip Repair System in Patients With Moderate or Greater TR; NCT03227757).

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

OBJECTIVES: The 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) BACKGROUND: Differences 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. METHODS: The 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. RESULTS: A 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. CONCLUSIONS: MD 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.

3D echocardiographic reference ranges for normal left ventricular volumes and strain: results from the EACVI NORRE study.

AIM: To obtain the normal ranges for 3D echocardiography (3DE) measurement of left ventricular (LV) volumes, function, and strain from a large group of healthy volunteers. METHODS AND RESULTS: A total of 440 (mean age: 45 ± 13 years) out of the 734 healthy subjects enrolled at 22 collaborating institutions of the Normal Reference Ranges for Echocardiography (NORRE) study had good-quality 3DE data sets that have been analysed with a vendor-independent software package allowing homogeneous measurements regardless of the echocardiographic machine used to acquire the data sets. Upper limits of LV end-diastolic and end-systolic volumes were larger in men (97 and 42 mL/m2) than in women (82 and 35 mL/m2; P < 0.0001). Conversely, lower limits of LV ejection fraction were higher in women than in men (51% vs. 50%; P < 0.01). Similarly, all strain components were higher in women than in men. Lower range was -18.6% in men and -19.5% in women for 3D longitudinal strain, -27.0% and -27.6% for 3D circumferential strain, -33.2% and -34.4% for 3D tangential strain and 38.8% and 40.7% for 3D radial strain, respectively. LV volumes decreased with age in both genders (P < 0.0001), whereas LV ejection fraction increased with age only in men. Among 3DE LV strain components, the only one, which did not change with age was longitudinal strain. CONCLUSION: The NORRE study provides applicable 3D echocardiographic reference ranges for LV function assessment. Our data highlight the importance of age- and gender-specific reference values for both LV volumes and strain.