In Vivo Computed Tomography Sizing for Redo-Transcatheter Aortic Valve Replacement in Evolut Valves: Impact on Sizing, Feasibility, and Prosthesis-Patient Mismatch.

BACKGROUND: SAPIEN3 (S3) is a ubiquitous redo-transcatheter aortic valve (TAV) replacement alternative for degenerated Evolut valves, but S3 sizing for S3-in-Evolut remains unclear. We sought to compare the impact of in vivo computed tomography (CT)-sizing on redo-TAV feasibility for S3-in-Evolut with traditional bench-sizing. METHODS: CT scans of 290 patients treated using Evolut R/PRO/PRO+ between July 2015 and December 2021 were analyzed. S3-in-Evolut was simulated using S3 outflow/neoskirt plane (NSP) at node-6, -5, and -4. CT-sizing for S3 was determined by averaging 4 areas of the Evolut stent frame at NSP level and 3 nodes below. Redo-TAV was deemed feasible if the NSP was below the coronaries, or the narrowest valve (virtual S3)-to-aorta distance was >4 mm. Risk of prosthesis-patient mismatch was estimated using predicted indexed-effective orifice area. RESULTS: Compared with bench-sizing, CT-sizing yielded smaller S3 size in 82% at node-6, 81% at node-5, and 84% at node-4. Factors associated with CT-sizing less than bench-sizing were larger index Evolut size, underexpansion of index Evolut, and shallower implant depth (all P<0.05). CT-sizing increased redo-TAV feasibility by +8% at node-6, +10% at node-5, and +4% at node-4. Redo-TAV feasibility increased with annulus size, sinotubular junction dimensions, coronary heights, index Evolut size, deeper Evolut implant depth, and lower NSP levels (all P<0.05). CT-sizing had a slightly higher estimated risk of severe prosthesis-patient mismatch (9% at node-6, 7% at node-5, and 6% at node-4), which could be mitigated by changing the NSP. CONCLUSIONS: CT-sizing for S3-in-Evolut is associated with higher feasibility of redo-TAV compared with bench-sizing, potentially reducing the risk of excessive oversizing and S3 underexpansion. Further validation using real-world clinical data is necessary.

AltaValve Atrial Fixation System for the Treatment of Severe Mitral Regurgitation and Mitral Annular Calcification.

Background: Treatment options for patients with mitral regurgitation (MR) and mitral annular calcification (MAC) are limited. The limitations of current transcatheter mitral valve replacement (TMVR) technologies include high screen failure rates, increased risk of left ventricular outflow tract obstruction, and high residual regurgitation. The aim of this study was to evaluate outcomes of TMVR with the AltaValve system (4C Medical, Maple Grove, MN), a supra-annular TMVR with atrial fixation, in patients with severe MR and moderate or severe MAC. Methods: Six patients with moderate or severe MAC who were treated with AltaValve TMVR had procedural and mid-term outcomes available. Results: Technical success was achieved in all patients. Median follow-up was 232 days. At discharge, 80% of patients had none/trace MR, and 20% had mild MR. There was no intraprocedural mortality, device malposition, embolization, or thrombosis. One patient expired 3 days postprocedure due to complications related to the transapical access. All other patients were discharged from the hospital without issues. Echocardiography assessments at 30 days showed complete resolution of MR in all patients, with 1 patient with mild MR and a mean mitral valve gradient of 3.7 ± 1.4 mmHg. All patients were in New York Heart Association Class I/II at 30-day follow-up, showing marked improvement as compared with baseline. Conclusions: In patients with severe MR and severe MAC, the AltaValve TMVR technology may represent a viable treatment option. The atrial fixation minimizes the risk of left ventricular outflow tract obstruction and potentially expands treatable patients, especially in patients with MAC.

New Insights and Perspective on Bioprosthetic Valve Fracture From Bench Testing and Computed Tomography Analysis.

Background: Bioprosthetic valve fracture (BVF) during valve-in-valve TAVR (transcatheter aortic valve replacement) is a procedural adjunct designed to optimize the expansion of the transcatheter heart valve and reduce patient-prosthesis mismatch by using a high-pressure balloon to intentionally fracture the surgical heart valve (SHV). Methods: We performed bench testing on 15 bioprosthetic SHV to examine the optimal balloon size and pressure for BVF. We assessed morphological changes and expansion of SHV by computed tomography angiography. Successful BVF was defined as balloon waist disappearance on fluoroscopy and/or sudden pressure drop during balloon inflation. Results: Nine valves met the definition of BVF, 3 of which were confirmed by disruption of the stent frame. We classified surgical valves into 3 subsets: 1) fracturable with metal stent frame (MSF), 2) fracturable with polymer stent frame (PSF) and 3) nonfracturable. In general, valves with MSF were fractured using a balloon size = true internal diameter plus 3-5 mm inflated at high pressure (16-20 ATM) whereas valves with PSF could be fractured with a balloon size = true internal diameter plus 3-5 mm and lower balloon pressure (6-14 ATM). Gains in computed tomography angiography derived inflow area after BVF were 12.3% for MSF and 3.6% for PSF SHV. Conclusions: Gains in CT-determined valve area after BVF depend on the physical properties of the SHV, which in turn influences pressure thresholds and balloon sizing strategy for optimal BVF. Elastic recoil of PSF valves limits the gains in inflow area after BVF.

Transcatheter heart valve explant with infective endocarditis-associated prosthesis failure and outcomes: the EXPLANT-TAVR international registry.

BACKGROUND AND AIMS: Surgical explantation of transcatheter heart valves (THVs) is rapidly increasing, but there are limited data on patients with THV-associated infective endocarditis (IE). This study aims to assess the outcomes of patients undergoing THV explant for IE. METHODS: All patients who underwent THV explant between 2011 and 2022 from 44 sites in the EXPLANT-TAVR registry were identified. Patients with IE as the reason for THV explant were compared to those with other mechanisms of bioprosthetic valve dysfunction (BVD). RESULTS: A total of 372 patients from the EXPLANT-TAVR registry were included. Among them, 184 (49.5%) patients underwent THV explant due to IE and 188 (50.5%) patients due to BVD. At the index transcatheter aortic valve replacement, patients undergoing THV explant for IE were older (74.3 ± 8.6 vs. 71 ± 10.6 years) and had a lower Society of Thoracic Surgeons risk score [2.6% (1.8-5.0) vs. 3.3% (2.1-5.6), P = .029] compared to patients with BVD. Compared to BVD, IE patients had longer intensive care unit and hospital stays (P < .05) and higher stroke rates at 30 days (8.6% vs. 2.9%, P = .032) and 1 year (16.2% vs. 5.2%, P = .010). Adjusted in-hospital, 30-day, and 1-year mortality was 12.1%, 16.1%, and 33.8%, respectively, for the entire cohort, with no significant differences between groups. Although mortality was numerically higher in IE patients 3 years postsurgery (29.6% for BVD vs. 43.9% for IE), Kaplan-Meier analysis showed no significant differences between groups (P = .16). CONCLUSIONS: In the EXPLANT-TAVR registry, patients undergoing THV explant for IE had higher 30-day and 1-year stroke rates and longer intensive care unit and hospital stays. Moreover, patients undergoing THV explant for IE had a higher 3-year mortality rate, which did not reach statistical significance given the relatively small sample size of this unique cohort and the reduced number of events.

Tricuspid Valve Leaflets-Lead Interaction: Adjunctive Role of Functional Cardiac Computed Tomography for Clinical Decision Making.

The diagnostic approach toward the management of cardiac implantable electronic device-related tricuspid regurgitation is challenging and undefined. Functional cardiac computed tomography angiography provides a complementary role to echocardiography in the evaluation of lead-leaflet interaction which can help the clinical decision-making process, as presented in this case series.

2-Year Clinical and Echocardiography Follow-Up of Transcatheter Mitral Valve Replacement With the Transapical Intrepid System.

BACKGROUND: Thirty-day outcomes with the investigational Intrepid transapical (TA) transcatheter mitral valve replacement (TMVR) system have previously demonstrated good technical success, but longer-term outcomes in larger cohorts need to be evaluated. OBJECTIVES: The authors sought to evaluate the 2-year safety and performance of the Intrepid TA-TMVR system in patients with symptomatic, ≥moderate-severe mitral regurgitation (MR) and high surgical risk. METHODS: Patient eligibility was determined by local heart teams and approved by a central screening committee. Clinical events were adjudicated by an independent clinical events committee. Echocardiography was evaluated by an independent core laboratory. RESULTS: The cohort included 252 patients that were enrolled at 58 international sites before February 2021 as part of the global Pilot Study (n = 95) or APOLLO trial (primary cohort noneligible + TA roll-ins, n = 157). Mean age was 74.2 years, mean STS-PROM was 6.3%, 60.3% were male, and 80.6% were in NYHA functional class III/IV. Most presented with secondary MR (70.1%), and nearly all had ≥moderate-severe MR (98.4%). All-cause mortality was 13.1% (30-day), 27.3% (1-year), and 36.2% (2-year). The 30-day ≥major bleeding event rate was 22.3%. Heart failure rehospitalization was 9.6% (30-day) and 36.2% (2-year). At 2 years, >50% of patients were alive with improvement in NYHA functional class (82.1%, class I/II), and all patients with available echocardiograms had ≤mild MR. CONCLUSIONS: This analysis represents the largest reported TA-TMVR experience with the longest follow-up in high-risk ≥moderate-severe MR patients. Early mortality and heart failure rehospitalizations were significant, exacerbated by early TA-related bleeding events; however, meaningful improvements in clinical outcomes and marked reductions in MR severity were observed through 2 years.

Contemporary 1-Year Outcomes of Mitral Valve-in-Ring With Balloon-Expandable Aortic Transcatheter Valves in the U.S.

BACKGROUND: Adequate valve performance after surgical mitral valve repair with an annuloplasty ring is not always sustained over time. The risk of repeat mitral valve surgery may be high in these patients. Transcatheter mitral valve-in-ring (MViR) is emerging as an alternative for high-risk patients. OBJECTIVES: The authors sought to assess contemporary outcomes of MViR using third-generation balloon-expandable aortic transcatheter heart valves. METHODS: Patients who underwent MViR and were enrolled in the STDS/ACC TVT (Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy) Registry between August 2015 and December 2022 were analyzed. RESULTS: A total of 820 patients underwent MViR at 236 sites, mean age was 72.2 ± 10.4 years, 50.9% were female, mean STS score was 8.2% ± 6.9%, and most (78%) were in NYHA functional class III to IV. Mean left ventricular ejection fraction was 47.8% ± 14.2%, mean mitral gradient was 8.9 ± 7.0 mm Hg, and 75.5% had ≥ moderate mitral regurgitation. Access was transseptal in 93.9% with 88% technical success. All-cause mortality at 30 days was 8.3%, and at 1 year, 22.4%, with a reintervention rate of 9.1%. At 1-year follow-up, 75.6% were NYHA functional class I to II, Kansas City Cardiomyopathy Questionnaire score increased by 25.9 ± 29.1 points, mean mitral valve gradient was 8.4 ± 3.4 mm Hg, and 91.7% had ≤ mild mitral regurgitation. CONCLUSIONS: MViR with third-generation balloon-expandable aortic transcatheter heart valves is associated with a significant reduction in mitral regurgitation and improvement in symptoms at 1 year, but with elevated valvular gradients and a high reintervention rate. MViR is a reasonable alternative for high-risk patients unable undergo surgery who have appropriate anatomy for the procedure. (STS/ACC TVT Registry Mitral Module [TMVR]; NCT02245763).

Deformation in transcatheter heart valves: Clinical implications and considerations.

Transcatheter aortic valve replacement (TAVR) has emerged as a preferred treatment modality for aortic stenosis, marking a significant advancement in cardiac interventions. Transcatheter heart valves (THVs) have also received approval for treating failed bioprosthetic valves and rings across aortic, mitral, tricuspid, and pulmonic positions. Unlike surgically implanted valves, which are sewn into the annulus, THVs are anchored through relative oversizing. Although THVs are designed to function optimally in a fully expanded state, they exhibit a certain degree of tolerance to underexpansion. However, significant deformation beyond this tolerance can adversely affect the valve's hemodynamics and durability, ultimately impacting patient outcomes. Such post-implantation deviations from the valve's intended three-dimensional design are influenced by a variety of physiological and anatomical factors unique to each patient and procedure, leading to underexpansion, eccentric expansion, and vertical deformation. These deformation patterns increase leaflet stress and strain, potentially causing fatigue and damage. This review article delves into the extent of THV deformation, its impact on leaflet function, hypoattenuating leaflet thickening, and structural valve degeneration. It provides an in-depth analysis of deformation specifics in different procedural contexts, including TAVR in native aortic stenosis, aortic and mitral valve-in-valve procedures, and redo-TAVR. Additionally, the review discusses strategies to mitigate THV deformation during the procedure, offering insights into potential solutions to these challenges.

Patient-Prosthesis Mismatch After Surgical Aortic Valve Replacement: Analysis of the PARTNER Trials.

BACKGROUND: Our objective was to compare the impact of patient-prosthesis mismatch (PPM) for 2 years after surgical aortic valve replacement within the prospective, randomized Placement of Aortic Transcatheter Valves (PARTNER) trials. METHODS: Surgical aortic valve replacement patients from the PARTNER 1, 2, and 3 trials were included. PPM was classified as moderate (indexed effective orifice area ≤0.85 cm2/m2) or severe (indexed effective orifice area ≤0.65 cm2/m2). The primary endpoint was the composite of all-cause death and heart failure rehospitalization at 2 years. RESULTS: By the predicted PPM method (PPMP), 59.1% had no PPM, 38.8% moderate PPM, and 2.1% severe PPM; whereas by the measured PPM method (PPMM), 42.4% had no PPM, 36.0% moderate, and 21.6% severe. Patients with no PPMP (23.6%) had a lower rate of the primary endpoint compared with patients with moderate (28.2%, P = .03) or severe PPMP (38.8%, P = .02). Using the PPMM method, there was no difference between the no (17.7%) and moderate PPMM groups (21.1%) in the primary outcome (P = .16). However, those with no PPMM or moderate PPMM were improved compared with severe PPMM (27.4%, P < .001 and P = .02, respectively). CONCLUSIONS: Severe PPM analyzed by PPMP was only 2.1% for surgical aortic valve replacement patients. The PPMM method overestimated the incidence of severe PPM relative to PPMP, but was also associated with worse outcome. There was higher all-cause mortality in patients with severe PPM, thus surgical techniques to minimize PPM remain critical.

Preprocedural Computed Tomography Planning for Surgical Aortic Valve Replacement.

BACKGROUND: Selection of transcatheter valve size using preprocedural computed tomography (CT) is standardized and well established. However, valve sizing for surgical aortic valve replacement (SAVR) is currently performed intraoperatively by using sizers, which may result in variation among operators and risk for prosthesis-patient mismatch. This study evaluated the usefulness of CT annulus measurement for SAVR valve sizing. METHODS: This study included patients who underwent SAVR using Inspiris or Magna Ease and received preoperative electrocardiogram-gated CT imaging. Starting from June 2022, study investigators applied a CT sizing algorithm using CT-derived annulus size to guide minimum SAVR label size. The final decision of valve selection was left to the operating surgeon during SAVR. The study compared the appropriateness of valve selection (comparing implanted size with CT-predicted size) and prosthesis-patient mismatch rates without aortic root enlargement between 2 cohorts: 102 cases since June 2022 (CT sizing cohort) and 180 cases from 2020 to 2021 (conventional sizing cohort). RESULTS: Implanted size smaller than CT predicted size and severe prosthesis-patient mismatch were significantly lower by CT sizing than by conventional sizing (12% vs 31% [P = .001] and 0% vs 6% [P = .039], respectively). Interoperator variability was a factor associated with implanted size smaller than CT predicted with conventional sizing, whereas it became nonsignificant with CT sizing. CONCLUSIONS: Applying CT sizing to SAVR led to improved valve size selection, less prosthesis-patient mismatch, and less interoperator variability. CT sizing for SAVR could also be used to predict prosthesis-patient mismatch before SAVR and identify patients who need aortic root enlargement.

Impact of transcatheter heart valve type on outcomes of surgical explantation after failed transcatheter aortic valve replacement: the EXPLANT-TAVR international registry.

BACKGROUND: There are limited data on the impact of transcatheter heart valve (THV) type on the outcomes of surgical explantation after THV failure. AIMS: We sought to determine the outcomes of transcatheter aortic valve replacement (TAVR) explantation for failed balloon-expandable valves (BEV) versus self-expanding valves (SEV). METHODS: From November 2009 to February 2022, 401 patients across 42 centres in the EXPLANT-TAVR registry underwent TAVR explantation during a separate admission from the initial TAVR. Mechanically expandable valves (N=10, 2.5%) were excluded. The outcomes of TAVR explantation were compared for 202 (51.7%) failed BEV and 189 (48.3%) failed SEV. RESULTS: Among 391 patients analysed (mean age: 73.0±9.8 years; 33.8% female), the median time from index TAVR to TAVR explantation was 13.3 months (interquartile range 5.1-34.8), with no differences between groups. Indications for TAVR explantation included endocarditis (36.0% failed SEV vs 55.4% failed BEV; p<0.001), paravalvular leak (21.2% vs 11.9%; p=0.014), structural valve deterioration (30.2% vs 21.8%; p=0.065) and prosthesis-patient mismatch (8.5% vs 10.4%; p=0.61). The SEV group trended fewer urgent/emergency surgeries (52.0% vs 62.3%; p=0.057) and more root replacement (15.3% vs 7.4%; p=0.016). Concomitant cardiac procedures were performed in 57.8% of patients, including coronary artery bypass graft (24.8%), and mitral (38.9%) and tricuspid (14.6%) valve surgery, with no differences between groups. In-hospital, 30-day, and 1-year mortality and stroke rates were similar between groups (allp>0.05), with no differences in cumulative mortality at 3 years (log-rank p=0.95). On multivariable analysis, concomitant mitral surgery was an independent predictor of 1-year mortality after BEV explant (hazard ratio [HR] 2.00, 95% confidence interval [CI]: 1.07-3.72) and SEV explant (HR 2.00, 95% CI: 1.08-3.69). CONCLUSIONS: In the EXPLANT-TAVR global registry, BEV and SEV groups had different indications for surgical explantation, with more root replacements in SEV failure, but no differences in midterm mortality and morbidities. Further refinement of TAVR explantation techniques are important to improving outcomes.

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.

Comprehensive Myocardial Assessment by Computed Tomography: Impact on Short-Term Outcomes After Transcatheter Aortic Valve Replacement.

BACKGROUND: Quantification of myocardial changes in severe aortic stenosis (AS) is prognostically important. The potential for comprehensive myocardial assessment pre-transcatheter aortic valve replacement (TAVR) by computed tomography angiography (CTA) is unknown. OBJECTIVES: This study sought to evaluate whether quantification of left ventricular (LV) extracellular volume-a marker of myocardial fibrosis-and global longitudinal strain-a marker of myocardial deformation-at baseline CTA associate with post-TAVR outcomes. METHODS: Consecutive patients with symptomatic severe AS between January 2021 and June 2022 who underwent pre-TAVR CTA were included. Computed tomography extracellular volume (CT-ECV) was derived from septum tracing after generating the 3-dimensional CT-ECV map. Computed tomography global longitudinal strain (CT-GLS) used semi-automated feature tracking analysis. The clinical endpoint was the composite outcome of all-cause mortality and heart failure hospitalization. RESULTS: Among the 300 patients (80.0 ± 9.4 years of age, 45% female, median Society of Thoracic Surgeons Predicted Risk of Mortality score 2.80%), the left ventricular ejection fraction (LVEF) was 58% ± 12%, the median CT-ECV was 28.5% (IQR: 26.2%-32.1%), and the median CT-GLS was -20.1% (IQR: -23.8% to -16.3%). Over a median follow-up of 16 months (IQR: 12-22 months), 38 deaths and 70 composite outcomes occurred. Multivariable Cox proportional hazards model, accounting for clinical and echocardiographic variables, demonstrated that CT-ECV (HR: 1.09 [95% CI: 1.02-1.16]; P = 0.008) and CT-GLS (HR: 1.07 [95% CI: 1.01-1.13]; P = 0.017) associated with the composite outcome. In combination, elevated CT-ECV and CT-GLS (above median for each) showed a stronger association with the outcome (HR: 7.14 [95% CI: 2.63-19.36]; P < 0.001). CONCLUSIONS: Comprehensive myocardial quantification of CT-ECV and CT-GLS associated with post-TAVR outcomes in a contemporary low-risk cohort with mostly preserved LVEF. Whether these imaging biomarkers can be potentially used for the decision making including timing of AS intervention and post-TAVR follow-up will require integration into future clinical trials.

Challenges and Future Directions in Redo Aortic Valve Reintervention After Transcatheter Aortic Valve Replacement Failure.

Transcatheter aortic valve replacement (TAVR) is increasingly being performed in younger and lower surgical risk patients. Reintervention for failed transcatheter heart valves will likely increase in the future as younger patients are expected to outlive the initial bioprosthesis. While redo-TAVR has emerged as an attractive and less invasive alternative to surgical explantation (TAVR-explant) to treat transcatheter heart valve failure, it may not be feasible in all patients due to the risk of coronary obstruction and impaired coronary access. Conversely, TAVR-explant can be offered to most patients who are surgical candidates, but the reported outcomes have shown high mortality and morbidity. This review provides the latest evidence, current challenges, and future directions on redo-TAVR and TAVR-explant for transcatheter heart valve failure, to guide aortic valve reintervention and facilitate patients' lifetime management of aortic stenosis.

Feasibility of Redo-Transcatheter Aortic Valve Replacement in Sapien Valves Based on In Vivo Computed Tomography Assessment.

BACKGROUND: Our aim was to assess the feasibility of repeat transcatheter aortic valve (TAV) replacement for degenerated Sapien3 (S3) prostheses by simulating subsequent implantation of S3 or Evolut, using in vivo computed tomography-based sizing and the impact on coronary and patient-prosthesis mismatch risks. METHODS: Computed tomography scans from 356 patients with prior S3 TAV replacement implantation were analyzed. The in vivo sizing for second TAV based on averaged area of 3 levels of outflow, mid (narrowest) and inflow, was compared with in vitro recommendations, that is, same size as index S3 for second S3 and 1 size larger for Evolut. Risks of coronary obstruction and patient-prosthesis mismatch were determined by valve-to-aorta distance and estimated effective orifice area, respectively. RESULTS: Overall, the majority of patients (n=328; 92.1%) had underexpanded index S3 with an expansion area of 94% (91%-97%), leading to significant differences in size selection of the second TAV between in vivo and in vitro sizing strategies. Expansion area <89% served as a threshold, resulting in 1 size smaller than the in vitro recommendations were selected in 45 patients (13%) for S3-in-S3 and 13 (4%) for Evolut-in-S3, while the remaining patients followed in vitro recommendations (P<0.01, in vivo versus in vitro sizing). Overall, 57% of total patients for S3-in-S3 simulation and 60% for Evolut-in-S3 were considered low risk for coronary complications. Deep index S3 implantation (odds ratio, 0.76 [interquartile range, 0.67-0.87]; P<0.001) and selecting Evolut as the second TAV (11% risk reduction in intermediate- or high-risk patients) reduced coronary risk. Estimated moderate or severe patient-prosthesis mismatch risk was 21% for S3-in-S3 and 1% for Evolut-in-S3, assuming optimal expansion of the second TAV. CONCLUSIONS: Redo-TAV replacement with S3-in-S3 and Evolut-in-S3 could be feasible with low risk to coronaries in ≈60% of patients, while the remaining 40% will be at intermediate or high risk. The feasibility of redo-TAV replacement is influenced by sizing strategy, type of second TAV, native annular anatomy, and implant depth.

Deformation of transcatheter heart valves with mitral valve-in-valve.

BACKGROUND: The use of oversizing in mitral valve-in-valve (MViV) procedures can lead to non-uniform expansion of transcatheter heart valves (THV). This may have implications for THV durability. AIMS: The objective of this study was to assess the extent and predictors of THV deformation in MViV procedures. METHODS: We examined 33 patients who underwent MViV with SAPIEN prostheses. The extent of THV deformation (deformation index, eccentricity, neosinus volume, asymmetric leaflet expansion and vertical deformation) and hypoattenuating leaflet thickening (HALT) were assessed using cardiac computed tomography (CT), performed prospectively at 30 days post-procedure. For descriptive purposes, the THV deformation index was calculated, with values >1.00 representing a more hourglass shape. RESULTS: Non-uniform underexpansion of THV was common after MViV implantation, with a median expansion area of 74.0% (interquartile range 68.1-84.1) at the narrowest level and a THV deformation index of 1.21 (1.13-1.29), but circularity was maintained with eccentricity ranging from 0.24 to 0.28. The degree of oversizing was a key factor associated with greater underexpansion and a higher deformation index (ß=-0.634; p<0.001; ß=0.594; p<0.001, respectively). Overall, the incidence of HALT on the 30-day postprocedural CT was 27.3% (9 of 33). Most patients (32 of 33) were on anticoagulation therapy, but the prothrombin time and international normalised ratio (PT-INR) at the time of the CT scan was <2.5 in 23 of 32 patients. Among patients with a PT-INR of <2.5, HALT was predominantly observed with a high THV deformation index of ≥1.18. CONCLUSIONS: THV deformation, i.e., underexpansion and an hourglass shape, commonly occurs after MViV implantation and is negatively affected by excessive oversizing. Optimising THV expansion during MViV could potentially prevent HALT.

1-Year Outcomes Following Transfemoral Transseptal Transcatheter Mitral Valve Replacement: Intrepid TMVR Early Feasibility Study Results.

BACKGROUND: High surgical risk may preclude mitral valve replacement in many patients. Transcatheter mitral valve replacement (TMVR) using transfemoral transseptal access is a novel technology for the treatment of mitral regurgitation (MR) in high-risk surgical patients. OBJECTIVES: This analysis evaluates 30-day and 1-year outcomes of the Intrepid TMVR Early Feasibility Study in patients with ≥moderate-severe MR. METHODS: The Intrepid TMVR Early Feasibility Study is a multicenter, prospective, single-arm study. Clinical events were adjudicated by a clinical events committee; endpoints were defined according to Mitral Valve Academic Research Consortium criteria. RESULTS: A total of 33 patients, enrolled at 9 U.S. sites between February 2020 and August 2022, were included. The median age was 80 years, 63.6% of patients were men, and mean Society of Thoracic Surgeons Predicted Risk of Mortality for mitral valve replacement was 5.3%. Thirty-one (93.9%) patients were successfully implanted. Median postprocedural hospitalization length of stay was 5 days, and 87.9% of patients were discharged to home. At 30 days, there were no deaths or strokes, 8 (24.2%) patients had major vascular complications and none required surgical intervention, there were 4 cases of venous thromboembolism all successfully treated without sequelae, and 1 patient had mitral valve reintervention for severe left ventricular outflow tract obstruction. At 1 year, the Kaplan-Meier all-cause mortality rate was 6.7%, echocardiography showed ≤mild valvular MR, there was no/trace paravalvular leak in all patients, median mitral valve mean gradient was 4.6 mm Hg (Q1-Q3: 3.9-5.3 mm Hg), and 91.7% of survivors were in NYHA functional class I/II with a median 11.4-point improvement in Kansas City Cardiomyopathy Questionnaire overall summary scores. CONCLUSIONS: The early benefits of the Intrepid transfemoral transseptal TMVR system were maintained up to 1 year with low mortality, low reintervention, and near complete elimination of MR, demonstrating a favorable safety profile and durable valve function.