Two-year follow-up of transcatheter aortic valve replacement in low-risk patients with symptomatic severe bicuspid aortic valve stenosis.

BACKGROUND: In 2019, the US Food and Drug Administration (FDA) approved transcatheter aortic valve replacement (TAVR) for low-risk patients with symptomatic severe tricuspid aortic stenosis. However, bicuspid aortic valve (BAV) patients were included only in single-arm registries of pivotal low-risk TAVR trials, resulting in limited data for this subgroup. METHODS: The LRT (Low Risk TAVR) trial was an investigator-initiated, prospective, multicenter study and the first FDA-approved investigational device exemption trial to evaluate the feasibility of TAVR with balloon-expandable or self-expanding valves in low-risk patients with symptomatic severe BAV stenosis. This analysis reports 2-year follow-up, assessing the primary outcome of all-cause mortality and evaluating clinical outcomes. RESULTS: From 2016 to 2019, a total of 72 low-risk patients diagnosed with symptomatic, severe BAV stenosis underwent TAVR across six centers. Six patients were lost to follow-up. At 2-year follow-up, mortality was 1.5% (1 of 66 patients). Among the remaining 65 patients, four experienced nondisabling strokes (6.2%), while 2 (3.1%) developed infective endocarditis. No new permanent pacemakers were required beyond the 30-day follow-up, and no patients, including those with endocarditis, needed aortic valve re-intervention. At the 2-year echocardiography follow-up (n = 65), 27.8% of BAV patients showed mild aortic regurgitation, with none exhibiting moderate or severe regurgitation. The mean aortic gradient was 12.1 ± 4.1 mmHg, and the mean valve area was 1.7 ± 0.5 cm². CONCLUSION: The 2-year follow-up confirms commendable clinical outcomes of TAVR in patients with bicuspid aortic stenosis, establishing its evident safety.

Self-expanding and balloon-expandable valves in low risk TAVR patients.

BACKGROUND: Recent randomized studies have broadened the indication of transcatheter aortic valve replacement (TAVR) to also include low-surgical-risk patients. However, the data on self-expanding (SE) and balloon-expandable (BE) valves in low-risk patients remain sparse. METHODS: The current study is a post hoc analysis of combined data from both LRT 1.0 and 2.0 trials comparing BE and SE transcatheter heart valves. RESULTS: A total of 294 patients received a BE valve, and 102 patients received an SE valve. The 30-day clinical outcomes were similar across both groups except for stroke (4.9% vs. 0.7%, p = 0.014) and permanent pacemaker implantation (17.8% vs. 5.8%, p < 0.001), which were higher in the SE cohort than the BE cohort. No difference was observed in terms of paravalvular leak (≥moderate) between the groups (0% vs. 1.5%, p = 0.577). SE patients had higher aortic valve area (1.92 ± 0.43 mm2 vs. 1.69 ± 0.45 mm2, p < 0.001) and lower mean gradient (8.93 ± 3.53 mmHg vs. 13.41 ± 4.73 mmHg, p < 0.001) than BE patients. In addition, the rate of subclinical leaflet thrombosis was significantly lower in SE patients (5.6% vs. 13.8%, p = 0.038). CONCLUSION: In this non-randomized study assessing SE and BE valves in low-risk TAVR patients, SE valves are associated with better hemodynamics and lesser leaflet thrombosis, with increased rates of stroke and permanent pacemaker implantation at 30 days; however, this could be due to certain patient-dependent factors not fully evaluated in this study. The long-term implications of these outcomes on structural valve durability remain to be further investigated. CLINICAL TRIAL REGISTRY: LRT 1.0: NCT02628899 LRT 2.0: NCT03557242.

Transcatheter Aortic Valve Replacement and Impact of Subclinical Leaflet Thrombosis in Low-Risk Patients: LRT Trial 4-Year Outcomes.

BACKGROUND: The LRT trial (Low-Risk Transcatheter Aortic Valve Replacement [TAVR]) demonstrated the safety and feasibility of TAVR in low-risk patients, with excellent 1- and 2-year outcomes. The objective of the current study is to provide the overall clinical outcomes and the impact of 30-day hypoattenuated leaflet thickening (HALT) on structural valve deterioration at 4 years. METHODS: The prospective, multicenter LRT trial was the first Food and Drug Administration-approved investigational device exemption study to evaluate feasibility and safety of TAVR in low-risk patients with symptomatic severe tricuspid aortic stenosis. Clinical outcomes and valve hemodynamics were documented annually through 4 years. RESULTS: A total of 200 patients were enrolled, and follow-up was available on 177 patients at 4 years. The rates of all-cause mortality and cardiovascular death were 11.9% and 3.3%, respectively. The stroke rate rose from 0.5% at 30 days to 7.5% at 4 years, and permanent pacemaker implantation rose from 6.5% at 30 days to 11.7% at 4 years. Endocarditis was detected in 2.5% of the cohort, with no new cases reported between 2 and 4 years. Transcatheter heart valve hemodynamics remained excellent post-procedure and were maintained (mean gradient 12.56±5.54 mm Hg and aortic valve area 1.69±0.52 cm2) at 4 years. At 30 days, HALT was observed in 14% of subjects who received a balloon-expandable transcatheter heart valve. There was no difference in valve hemodynamics between patients with and without HALT (mean gradient 14.94±5.01 mm Hg versus 12.3±5.57 mm Hg; P=0.23) at 4 years. The overall rate of structural valve deterioration was 5.8%, and there was no impact of HALT on valve hemodynamics, endocarditis, or stroke at 4 years. CONCLUSIONS: TAVR in low-risk patients with symptomatic severe tricuspid aortic stenosis was found to be safe and durable at 4 years. Structural valve deterioration rates were low irrespective of the type of valve, and the presence of HALT at 30 days did not affect structural valve deterioration, transcatheter valve hemodynamics, and stroke rate at 4 years. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02628899.

Subclinical leaflet thrombosis and antithrombotic therapy post-TAVI: An LRT substudy.

BACKGROUND: Subclinical leaflet thrombosis (SLT) is characterized on computed tomography (CT) imaging as hypoattenuated leaflet thickening (HALT), reduced leaflet motion (RELM), and hypoattenuation affecting motion (HAM). How antithrombotic regimen type impacts SLT remains poorly understood. We evaluated how antithrombotic regimen type impacts SLT in low-risk subjects following transcatheter aortic valve implantation (TAVI). METHODS: This substudy is a post hoc analysis of the LRT 1.0 and 2.0 trials to assess SLT in subjects who underwent CT or transoesophageal echocardiogram (TOE) imaging at 30 days, stratified by antithrombotic regimen received (single antiplatelet therapy [SAPT], dual antiplatelet therapy [DAPT], or oral anticoagulation). We also utilized univariable logistic regression modelling to identify echocardiographic predictors of HALT. RESULTS: Rates of HALT, RELM, and HAM were all significantly lower with oral anticoagulation compared to SAPT or DAPT at 30 days (HALT: 2.6% vs 14.3% vs 17.2%, respectively, with p < 0.001; RELM: 1.8% vs 9.6% vs 13.1%, respectively, with p = 0.004; and HAM: 0.9% vs 8.5% vs 9.8%, respectively, with p = 0.011). Additionally, short-term oral anticoagulation was not associated with higher bleeding rates compared to SAPT or DAPT (0.8% vs. 1.8% vs. 3.6%, p = 0.291). The presence of HALT did not significantly impact echocardiographic haemodynamic parameters at 30 days. CONCLUSION: This is the largest study to date that evaluated the impact of different antithrombotic regimens on SLT in low-risk TAVI patients. Oral anticoagulation was associated with significantly lower rates of SLT at 30 days compared to DAPT or SAPT, and there was no apparent benefit of DAPT over SAPT.

Long-term Outcomes of Transcatheter Aortic Valve Replacement With the Lotus Valve vs CoreValve/EvolutR: A Secondary Analysis of the REPRISE III Randomized Clinical Trial.

Importance: Long-term follow-up after transcatheter aortic valve replacement (TAVR) is of interest given that longitudinal data on mortality and durability of transcatheter heart valves are limited. The REPRISE III (Repositionable Percutaneous Replacement of Stenotic Aortic Valve Through Implantation of Lotus Valve System-Randomized Clinical Evaluation) randomized clinical trial compared the mechanically expanded Lotus valve with the self-expanding CoreValve/EvolutR TAVR platforms. Objective: To describe the final 5-year outcomes of the REPRISE III trial. Design, Setting, and Participants: This prespecified secondary analysis assessed the final 5-year clinical, functional, and echocardiographic outcomes of 912 patients from the REPRISE III trial, which was conducted at 55 centers in North America, Europe, and Australia between September 22, 2014, and December 24, 2015. Patients had high risk for aortic stenosis or severe or symptomatic aortic stenosis. Data were analyzed from September 22, 2014, to May 21, 2021. Intervention: Lotus valve or CoreValve/EvolutR TAVR platforms. Main Outcomes and Measures: Valve Academic Research Consortium-2 end points, hemodynamic measures, functional status, and health status were examined through the 5-year follow-up. Results: A total of 912 patients (mean [SD] age, 82.8 [7.3] years; 463 women [50.8%]) were randomized to either the Lotus valve group (n = 607) or CoreValve/EvolutR group (n = 305), with a baseline Society of Thoracic Surgeons risk score of 6.8%. Clinical follow-up data from the REPRISE III trial were available for 581 patients (95.7%) in the Lotus valve group and 285 patients (93.4%) in the CoreValve/EvolutR group. At 5 years, the cumulative event rate for all-cause mortality was 50.9% in the Lotus valve group vs 52.8% in the CoreValve/EvolutR group (P = .59). Disabling stroke was less frequent with the Lotus valve vs CoreValve/EvolutR (cumulative event rates, 8.3% vs 12.2%; P = .04), whereas the cumulative event rates for overall stroke were similar in both groups (14.1% vs 15.3%; P = .38). Insertion of a new permanent pacemaker (38.9% vs 27.3%; P < .001) and detection of prosthetic aortic valve thrombosis (5.8% vs 1.8%; P = .007) were more common in the Lotus valve group than in the CoreValve/EvolutR group. A smaller proportion of patients who received the Lotus valve experienced valve malpositioning (0% vs 2.6%; P < .001) and required the use of a second valve (1.0% vs 3.8%; P < .001) during the procedure compared with those who received the CoreValve/EvolutR. Compared with the Lotus valve group, the CoreValve/EvolutR group had a significantly lower mean (SD) aortic gradient (7.8 [4.2] mm Hg vs 12.6 [6.7] mm Hg; P < .001) and larger valve areas (1.57 [0.56] cm2 vs 1.42 [0.42] cm2; P = .10). After 5 years, the proportion of patients with moderate or greater paravalvular leak was not significantly higher with the CoreValve/EvolutR than with the Lotus valve (1.9% vs 0%; P = .31); however, the proportion of patients with mild paravalvular leak was higher in the CoreValve/EvolutR group compared with the Lotus valve group (23.1% vs 7.8%; P = .006). Long-term, similar improvements in New York Heart Association class and Kansas City Cardiomyopathy Questionnaire score were observed in both groups. Conclusions and Relevance: The REPRISE III trial found that, at 5 years, the clinical outcomes of the Lotus valve were comparable to those of the CoreValve/EvolutR and that the Lotus valve was safe and effective. Trial Registration: ClinicalTrials.gov Identifier: NCT02202434.

Lifetime management of patients with symptomatic severe aortic stenosis: a computed tomography simulation study.

BACKGROUND: Given enough time, transcatheter heart valves (THVs) will degenerate and may require reintervention. Redo transcatheter aortic valve implantation (TAVI) is an attractive strategy but carries a risk of coronary obstruction. AIMS: We sought to predict how many TAVIs patients could undergo in their lifetime using computed tomography (CT) simulation. METHODS: We analysed paired CT scans (baseline and 30 days post-TAVI) from patients in the LRT trial and EPROMPT registry. We implanted virtual THVs on baseline CTs, comparing predicted valve-to-coronary (VTC) distances to 30-day CT VTC distances to evaluate the accuracy of CT simulation. We then simulated implantation of a second virtual THV within the first to estimate the risk of coronary obstruction due to sinus sequestration and the need for leaflet modification. RESULTS: We included 213 patients with evaluable paired CTs. There was good agreement between virtual (baseline) and actual (30 days) CT measurements. CT simulation of TAVI followed by redo TAVI predicted low coronary obstruction risk in 25.4% of patients and high risk, likely necessitating leaflet modification, in 27.7%, regardless of THV type. The remaining 46.9% could undergo redo TAVI so long as the first THV was balloon-expandable but would likely require leaflet modification if the first THV was self-expanding. CONCLUSIONS: Using cardiac CT simulation, it is possible to predict whether a patient can undergo multiple TAVI procedures in their lifetime. Those who cannot may prefer to undergo surgery first. CT simulation could provide a personalised lifetime management strategy for younger patients with symptomatic severe aortic stenosis and inform decision-making. CLINICALTRIALS: gov: NCT02628899; ClinicalTrials.gov: NCT03557242; ClinicalTrials.gov: NCT03423459.

Balloon-Expandable Valve Geometry After Transcatheter Aortic Valve Replacement in Low-Risk Patients With Bicuspid Versus Tricuspid Aortic Stenosis.

BACKGROUND: Prospective bicuspid low-risk transcatheter aortic valve replacement (TAVR) registries' data demonstrated encouraging short-term results. Detailed data on transcatheter heart valve (THV) geometry after deployment using contemporary devices are lacking. This study sought to examine valve geometry after TAVR in patients with bicuspid aortic stenosis (AS). METHODS: The study population was patients from the LRT (Low Risk TAVR) trial who underwent TAVR using the SAPIEN 3 THV for bicuspid and tricuspid AS. THV geometry measured on 30-day computed tomography (CT) included valve height, angle, depth, and eccentricity. Additionally, THV hemodynamics and outcomes post-TAVR were compared among patients with bicuspid and tricuspid AS. RESULTS: A total of 107 patients from the LRT trial using the SAPIEN 3 THV were included in our analysis. On 30-day CT, the valve height ratio (1.07 vs. 1.07; p = 0.348), depths (right [5.6 mm vs. 6.2 mm; p = 0.223], left [5.3 mm vs. 4.4 mm; p = 0.082] and non [4.8 mm vs. 4.5 mm; p = 0.589] coronary cusps), eccentricities (1.08 vs. 1.07; p = 0.9550), and angles (except the right [3.9 degrees vs. 6.3 degrees; p = 0.003] and left [3.6 degrees vs. 6.0 degrees; p = 0.007]) were similar between bicuspid and tricuspid patients. Hemodynamics, stroke, and mortality were similar at 1 year. CONCLUSION: Despite challenging bicuspid anatomy of the aortic valve, our comprehensive CT analysis supports similar THV geometry between patients with bicuspid and tricuspid AS undergoing TAVR using the SAPIEN 3 THV in low-risk patients. This translated to excellent short-term clinical outcomes and THV hemodynamics in both aortic valve morphologies. TRIAL REGISTRY: NCT02628899, https://clinicaltrials.gov/ct2/show/NCT02628899.

Transcatheter aortic valve replacement in low-risk patients: 2-year results from the LRT trial.

BACKGROUND: Previous studies from the Low Risk TAVR (LRT) trial demonstrated that transcatheter aortic valve replacement (TAVR) is safe and feasible in low-risk patients, with excellent 30-day and 1-year outcomes. The objective of this study was to report clinical outcomes and the impact of 30-day hypoattenuated leaflet thickening (HALT) on structural valve deterioration (SVD) 2 years after TAVR. METHODS: The LRT trial was the first Food and Drug Administration-approved Investigational Device Exemption trial in the United States to evaluate the safety and feasibility of TAVR in low-risk patients with symptomatic severe tricuspid aortic stenosis (AS). Valve hemodynamics and SVD by echo were recorded 30 days, 1 year, and 2 years post-TAVR. RESULTS: The LRT trial enrolled 200 low-risk patients to receive TAVR. Their mean age was 73.6 years and 61.5% were men. At 2-year follow-up, the mortality rate was 4.2%; the cardiovascular death rate was 1.6%. The disabling stroke rate was 1.1%, permanent pacemaker implantation rate was 8.6%, and 4 patients (2.2%) presented with endocarditis (2 between years 1 and 2). Of the 14% of TAVR subjects who had evidence of HALT at 30 days, there was no impact on valve hemodynamics, endocarditis or stroke at 2 years. CONCLUSIONS: TAVR for low-risk patients with symptomatic severe tricuspid AS is safe at 2 years. The presence of HALT at 30 days did not impact the early hemodynamic improvements nor the durability of the valve structure.

Randomized Trial of Aspirin Versus Warfarin After Transcatheter Aortic Valve Replacement in Low-Risk Patients.

BACKGROUND: The optimal antithrombotic regimen after transcatheter aortic valve replacement remains unclear. METHODS: In this randomized open-label study, low-risk patients undergoing transfemoral transcatheter aortic valve replacement at 7 centers in the United States were randomized 1:1 to low-dose aspirin or warfarin plus low-dose aspirin for 30 days. Patients who could not be randomized were enrolled in a separate registry. Computed tomography or transesophageal echocardiography was performed at 30 days. The primary effectiveness end point was a composite of the following at 30 days: hypoattenuated leaflet thickening, at least moderately reduced leaflet motion, hemodynamic dysfunction (mean aortic valve gradient ≥20 mm Hg, effective orifice area ≤1.0 cm2, dimensionless valve index <0.35, or moderate or severe aortic regurgitation), stroke, or transient ischemic attack. RESULTS: Between July 2018 and October 2019, 94 patients were randomly assigned, 50 to aspirin and 44 to warfarin plus aspirin, and 30 were enrolled into the registry. In the intention-to-treat analysis of the randomized cohort, the composite primary effectiveness end point was met in 26.5% for aspirin versus 7.0% for warfarin plus aspirin (P=0.014; odds ratio, 4.8 [95% CI, 1.3-18.3]). The rate of hypoattenuated leaflet thickening was 16.3% for aspirin versus 4.7% for warfarin plus aspirin (P=0.07; odds ratio, 4.0 [95% CI, 0.8-20.0]). There was no excess bleeding at 30 days with anticoagulation. In the as-treated analysis of pooled randomized and registry cohorts, the rate of hypoattenuated leaflet thickening was 16.7% for aspirin versus 3.1% for warfarin plus aspirin (P=0.011; odds ratio, 6.3 [95% CI, 1.3-30.6]). CONCLUSIONS: In low-risk transcatheter aortic valve replacement patients, anticoagulation with warfarin may prevent transcatheter heart valve dysfunction in the short term without excess bleeding. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03557242.

Anatomical Characteristics Associated With Hypoattenuated Leaflet Thickening in Low-Risk Patients Undergoing Transcatheter Aortic Valve Replacement.

BACKGROUND/PURPOSE: This sub-analysis of the prospective Low Risk TAVR (LRT) trial determined anatomical characteristics associated with hypoattenuated leaflet thickening (HALT), which may contribute to early transcatheter heart valve (THV) degeneration. METHODS/MATERIALS: The LRT trial enrolled 200 low-risk patients between February 2016 and February 2018. All subjects underwent baseline and 30-day CT studies, analyzed by an independent core laboratory. Additional measurements, namely THV expansion, eccentricity, depth, and commissural alignment, were made by consensus of three independent readers. HALT was observed only in the Sapien 3 THV, so Evolut valves were excluded from this analysis. RESULTS: In the LRT trial, 177 subjects received Sapien 3 THVs, of whom 167 (94.3%) had interpretable 30-day CTs and were eligible for this analysis. Twenty-six subjects had HALT (15.6%). Baseline characteristics were similar between groups. There was no difference in THV size implanted and baseline aortic-root geometry between groups. In patients who developed HALT, THV implantation depth was shallower than in patients who did not develop HALT (2.6 ± 1.1 mm HALT versus 3.3 ± 1.8 mm no-HALT, p = 0.03). There were more patients in the HALT group with commissural malalignment (40% vs. 28%; p = 0.25), but this did not reach statistical significance. In a univariable regression model, no predetermined variables were shown to independently predict the development of HALT. CONCLUSIONS: This study did not find anatomical or THV implantation characteristics that predicted the development of HALT at 30 days. This study cannot exclude subtle effects or interaction between factors because of the small number of events.

Feasibility of Coronary Access and Aortic Valve Reintervention in Low-Risk TAVR Patients.

OBJECTIVES: The aim of this study was to evaluate the feasibility of coronary access and aortic valve reintervention in low-risk patients undergoing transcatheter aortic valve replacement (TAVR) with a balloon-expandable transcatheter heart valve (THV). BACKGROUND: Younger, low-risk TAVR patients are more likely than older, higher risk patients to require coronary angiography, percutaneous coronary intervention, or aortic valve reintervention, but their THVs may impede coronary access and cause coronary obstruction during TAVR-in-TAVR. METHODS: The LRT (Low Risk TAVR) trial (NCT02628899) enrolled 200 subjects with symptomatic severe aortic stenosis to undergo TAVR using commercially available THVs. Subjects who received balloon-expandable THVs and who had 30-day cardiac computed tomographic scans were included in this study. In a subgroup, the feasibility of intentional THV crimping on the delivery catheter to pre-determine commissural alignment was tested. RESULTS: In the LRT trial, 168 subjects received balloon-expandable THVs and had 30-day cardiac computed tomographic scans, of which 137 were of adequate image quality for analysis. The most challenging anatomy for coronary access (THV frame above and commissural suture post in front of a coronary ostium) was observed in 9% to 13% of subjects. Intentional THV crimping did not appear to meaningfully affect commissural alignment. The THV frame extended above the sinotubular junction in 21% of subjects, and in 13%, the distance between the THV and the sinotubular junction was <2 mm, signifying that TAVR-in-TAVR may not be feasible without causing coronary obstruction. CONCLUSIONS: TAVR may present challenges to future coronary access and aortic valve reintervention in a substantial number of low-risk patients.

Coronary Artery Disease Assessed by Computed Tomography-Based Leaman Score in Patients With Low-Risk Transcatheter Aortic Valve Implantation.

We aimed to evaluate the burden of coronary artery disease (CAD) using the computed tomography (CT) Leaman score in low-risk transcatheter aortic valve implantation (TAVI) patients. The extent of CAD in low-risk patients with aortic stenosis who are candidates for TAVI has not been accurately quantified. The CT Leaman score was developed to quantify coronary CT angiography (CCTA) atherosclerotic burden and has been validated to evaluate the extent of CAD. CT Leaman score >5 has been associated with an increase in major adverse cardiac events over long-term follow-up. The study population included patients enrolled in the Low Risk TAVI trial who underwent CCTA before the procedure. For the CT Leaman score, we used 3 sets of weighting factors: (1) location of coronary plaques, (2) type of plaque, and (3) degree of stenosis. A total of 200 patients were enrolled in the Low Risk TAVI trial. Excluded were 31 patients who had no analyzable CCTA imaging. For the remaining 169 patients, the mean CT Leaman score was 6.27 ± 0.27, of whom 102 (60.4%) had CT Leaman score >5. Nearly all analyzed patients (97%) had coronary plaques. Furthermore, 33 patients (19.5%) had potentially obstructive coronary plaques (>50% stenosis by CCTA) in proximal segments. Most low-risk TAVI patients have significant CAD burden by CCTA. It should be a priority for future TAVI devices to guarantee unimpeded access to the coronary arteries for selective angiography and interventions.

Hemodynamics and Subclinical Leaflet Thrombosis in Low-Risk Patients Undergoing Transcatheter Aortic Valve Replacement.

BACKGROUND: This analysis evaluated echocardiographic predictors of hypoattenuated leaflet thickening (HALT) in low-risk patients undergoing transcatheter aortic valve replacement and assessed 1-year clinical and hemodynamic consequences. HALT by computed tomography may be associated with early valve degeneration and increased neurological events. METHODS: Echocardiograms were performed at baseline, discharge, 30 days, and 1 year post-procedure. Four-dimensional contrast-enhanced computed tomography assessed HALT at 30 days. Independent core laboratories analyzed images. Doppler hemodynamic parameters were tested in a univariable regression model to identify HALT predictors. One-year clinical and hemodynamic outcomes were compared between HALT (+) and (-) patients. RESULTS: Analysis included 170 patients with Sapien 3 valves and diagnostic 30-day computed tomographies, of whom 27 (16%) had HALT. Baseline characteristics were similar between groups. After transcatheter aortic valve replacement, aortic flow was nonsignificantly reduced in patients who developed HALT. Regression analysis did not show significant association between baseline or discharge valve hemodynamics and development of HALT at 30 days. Patients with HALT had smaller aortic valve areas (1.4±0.4 versus 1.7±0.5 cm2; P=0.018) and Doppler velocity index (0.4±0.1 versus 0.5±0.1; P=0.003) than those without HALT at 30 days but not at 1 year. There was no difference in aortic mean gradient at 30 days. There was no difference between the groups in New York Heart Association class, 6-minute walk distance, and mortality at 1 year. CONCLUSIONS: There were no early hemodynamic predictors of HALT. At 30 days, patients with HALT had worse valve hemodynamics than those without HALT, but hemodynamic and clinical outcomes at 1 year were similar. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02628899.

Outcomes of Veterans Undergoing TAVR Within Veterans Affairs Medical Centers: Insights From the Veterans Affairs Clinical Assessment, Reporting, and Tracking Program.

OBJECTIVES: This study sought to describe clinical and procedural characteristics of veterans undergoing transcatheter aortic valve replacement (TAVR) within U.S. Department of Veterans Affairs (VA) centers and to examine their association with short- and long-term mortality, length of stay (LOS), and rehospitalization within 30 days. BACKGROUND: Veterans with severe aortic stenosis frequently undergo TAVR at VA medical centers. METHODS: Consecutive veterans undergoing TAVR between 2012 and 2017 were included. Patient and procedural characteristics were obtained from the VA Clinical Assessment, Reporting, and Tracking system. The primary outcomes were 30-day and 1-year survival, LOS >6 days, and rehospitalization within 30 days. Logistic regression and Cox proportional hazards analyses were performed to evaluate the associations between pre-procedural characteristics and LOS and rehospitalization. RESULTS: Nine hundred fifty-nine veterans underwent TAVR at 8 VA centers during the study period, 860 (90%) by transfemoral access, 50 (5%) transapical, 36 (3.8%) transaxillary, and 3 (0.3%) transaortic. Men predominated (939 of 959 [98%]), with an average age of 78.1 years. There were 28 deaths within 30 days (2.9%) and 134 at 1 year (14.0%). Median LOS was 5 days, and 141 veterans were rehospitalized within 30 days (14.7%). Nonfemoral access (odds ratio: 1.74; 95% confidence interval [CI]: 1.10 to 2.74), heart failure (odds ratio: 2.51; 95% CI: 1.83 to 3.44), and atrial fibrillation (odds ratio: 1.40; 95% CI: 1.01 to 1.95) were associated with increased LOS. Atrial fibrillation was associated with 30-day rehospitalization (hazard ratio: 1.79; 95% CI: 1.22 to 2.63). CONCLUSIONS: Veterans undergoing TAVR at VA centers are predominantly elderly men with significant comorbidities. Clinical outcomes of mortality and rehospitalization at 30 days and 1-year mortality compare favorably with benchmark outcome data outside the VA.

TAVR in Low-Risk Patients: 1-Year Results From the LRT Trial.

OBJECTIVES: This study sought to evaluate clinical outcomes and transcatheter heart valve hemodynamics at 1 year after transcatheter aortic valve replacement (TAVR) in low-risk patients. BACKGROUND: Early results from the LRT (Low Risk TAVR) trial demonstrated that TAVR is safe in patients with symptomatic severe aortic stenosis who are at low risk for surgical valve replacement. METHODS: The LRT trial was an investigator-initiated, prospective, multicenter study and was the first Food and Drug Administration-approved Investigational Device Exemption trial to evaluate feasibility of TAVR in low-risk patients. The primary endpoint was all-cause mortality at 30 days. Secondary endpoints included clinical outcomes and valve hemodynamics at 1 year. RESULTS: The LRT trial enrolled 200 low-risk patients with symptomatic severe AS to undergo TAVR at 11 centers. Mean age was 73.6 years and 61.5% were men. At 30 days, there was zero mortality, zero disabling stroke, and low permanent pacemaker implantation rate (5.0%). At 1-year follow-up, mortality was 3.0%, stroke rate was 2.1%, and permanent pacemaker implantation rate was 7.3%. Two (1.0%) subjects underwent surgical reintervention for endocarditis. Of the 14% of TAVR subjects who had evidence of hypoattenuated leaflet thickening at 30 days, there was no impact on valve hemodynamics at 1 year, but the stroke rate was numerically higher (3.8% vs. 1.9%; p = 0.53). CONCLUSIONS: TAVR in low-risk patients with symptomatic severe aortic stenosis appears to be safe at 1 year. Hypoattenuated leaflet thickening, observed in a minority of TAVR patients at 30 days, did not have an impact on valve hemodynamics in the longer term.

Effect of Mechanically Expanded vs Self-Expanding Transcatheter Aortic Valve Replacement on Mortality and Major Adverse Clinical Events in High-Risk Patients With Aortic Stenosis: The REPRISE III Randomized Clinical Trial.

Importance: Transcatheter aortic valve replacement (TAVR) is established for selected patients with severe aortic stenosis. However, limitations such as suboptimal deployment, conduction disturbances, and paravalvular leak occur. Objective: To evaluate if a mechanically expanded valve (MEV) is noninferior to an approved self-expanding valve (SEV) in high-risk patients with aortic stenosis undergoing TAVR. Design, Setting, and Participants: The REPRISE III trial was conducted in 912 patients with high or extreme risk and severe, symptomatic aortic stenosis at 55 centers in North America, Europe, and Australia between September 22, 2014, and December 24, 2015, with final follow-up on March 8, 2017. Interventions: Participants were randomized in a 2:1 ratio to receive either an MEV (n = 607) or an SEV (n = 305). Main Outcomes and Measures: The primary safety end point was the 30-day composite of all-cause mortality, stroke, life-threatening or major bleeding, stage 2/3 acute kidney injury, and major vascular complications tested for noninferiority (margin, 10.5%). The primary effectiveness end point was the 1-year composite of all-cause mortality, disabling stroke, and moderate or greater paravalvular leak tested for noninferiority (margin, 9.5%). If noninferiority criteria were met, the secondary end point of 1-year moderate or greater paravalvular leak was tested for superiority in the full analysis data set. Results: Among 912 randomized patients (mean age, 82.8 [SD, 7.3] years; 463 [51%] women; predicted risk of mortality, 6.8%), 874 (96%) were evaluable at 1 year. The primary safety composite end point at 30 days occurred in 20.3% of MEV patients and 17.2% of SEV patients (difference, 3.1%; Farrington-Manning 97.5% CI, -∞ to 8.3%; P = .003 for noninferiority). At 1 year, the primary effectiveness composite end point occurred in 15.4% with the MEV and 25.5% with the SEV (difference, -10.1%; Farrington-Manning 97.5% CI, -∞ to -4.4%; P<.001 for noninferiority). The 1-year rates of moderate or severe paravalvular leak were 0.9% for the MEV and 6.8% for the SEV (difference, -6.1%; 95% CI, -9.6% to -2.6%; P < .001). The superiority analysis for primary effectiveness was statistically significant (difference, -10.2%; 95% CI, -16.3% to -4.0%; P < .001). The MEV had higher rates of new pacemaker implants (35.5% vs 19.6%; P < .001) and valve thrombosis (1.5% vs 0%) but lower rates of repeat procedures (0.2% vs 2.0%), valve-in-valve deployments (0% vs 3.7%), and valve malpositioning (0% vs 2.7%). Conclusions and Relevance: Among high-risk patients with aortic stenosis, use of the MEV compared with the SEV did not result in inferior outcomes for the primary safety end point or the primary effectiveness end point. These findings suggest that the MEV may be a useful addition for TAVR in high-risk patients. Trial Registration: ClinicalTrials.gov Identifier: NCT02202434.

5-Year Outcomes After Left Atrial Appendage Closure: From the PREVAIL and PROTECT AF Trials.

BACKGROUND: The PROTECT AF (WATCHMAN Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation) trial demonstrated that left atrial appendage closure (LAAC) with the Watchman device (Boston Scientific, St. Paul, Minnesota) was equivalent to warfarin for preventing stroke in atrial fibrillation, but had a high rate of complications. In a second randomized trial, PREVAIL (Evaluation of the WATCHMAN LAA Closure Device in Patients With Atrial Fibrillation Versus Long Term Warfarin Therapy), the complication rate was low. The warfarin cohort experienced an unexpectedly low ischemic stroke rate, rendering the efficacy endpoints inconclusive. However, these outcomes were based on relatively few patients followed for a relatively short time. OBJECTIVES: The final results of the PREVAIL trial, both alone and as part of a patient-level meta-analysis with the PROTECT AF trial, are reported with patients in both trials followed for 5 years. METHODS: PREVAIL and PROTECT AF are prospective randomized clinical trials with patients randomized 2:1 to LAAC or warfarin; together, they enrolled 1,114 patients for 4,343 patient-years. Analyses are by intention-to-treat, and rates are events per 100 patient-years. RESULTS: For the PREVAIL trial, the first composite coprimary endpoint of stroke, systemic embolism (SE), or cardiovascular/unexplained death did not achieve noninferiority (posterior probability for noninferiority = 88.4%), whereas the second coprimary endpoint of post-procedure ischemic stroke/SE did achieve noninferiority (posterior probability for noninferiority = 97.5%); the warfarin arm maintained an unusually low ischemic stroke rate (0.73%). In the meta-analysis, the composite endpoint was similar between groups (hazard ratio [HR]: 0.820; p = 0.27), as were all-stroke/SE (HR: 0.961; p = 0.87). The ischemic stroke/SE rate was numerically higher with LAAC, but this difference did not reach statistical significance (HR: 1.71; p = 0.080). However, differences in hemorrhagic stroke, disabling/fatal stroke, cardiovascular/unexplained death, all-cause death, and post-procedure bleeding favored LAAC (HR: 0.20; p = 0.0022; HR: 0.45; p = 0.03; HR: 0.59; p = 0.027; HR: 0.73; p = 0.035; HR: 0.48; p = 0.0003, respectively). CONCLUSIONS: These 5-year outcomes of the PREVAIL trial, combined with the 5-year outcomes of the PROTECT AF trial, demonstrate that LAAC with Watchman provides stroke prevention in nonvalvular atrial fibrillation comparable to warfarin, with additional reductions in major bleeding, particularly hemorrhagic stroke, and mortality. (WATCHMAN Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation; NCT00129545; and Evaluation of the WATCHMAN LAA Closure Device in Patients With Atrial Fibrillation Versus Long Term Warfarin Therapy; NCT01182441).

The Assessment of the Watchman Device in Patients Unsuitable for Oral Anticoagulation (ASAP-TOO) trial.

BACKGROUND: Oral anticoagulants (OACs) reduce stroke risks with nonvalvular atrial fibrillation (AF); however, they are underused because of absolute or relative contraindications due to real or perceived risk of bleeding. Although left atrial appendage closure is increasingly performed in OAC-ineligible patients, this has not been studied in a randomized controlled trial. STUDY OBJECTIVES: The ASAP-TOO study is designed to establish the safety and effectiveness of the Watchman left atrial appendage closure device in patients with nonvalvular AF who are deemed ineligible for OAC. The primary effectiveness end point is the time to first occurrence of ischemic stroke or systemic embolism. The primary safety end point includes all-cause death, ischemic stroke, systemic embolism, or device- or procedural-related event requiring open cardiac surgery or major endovascular intervention. STUDY DESIGN: This is a multinational, multicenter prospective randomized trial. Patients meeting the inclusion criteria with CHA2DS2-VASc score≥2 and who are deemed by 2 study physicians to be unsuitable for OAC will be randomized in a 2:1 allocation ratio to Watchman versus control. Control patients will be prescribed single antiplatelet therapy or no therapy at the discretion of the study physician. Up to 888 randomized subjects will be enrolled from up to 100 global investigational sites. Both device group and control patients will have follow-up visits at 3, 6, and 12months and then every 6months through 60months. SUMMARY: This trial will assess the safety and efficacy of Watchman in this challenging population of high-stroke risk AF patients.

Post-Approval U.S. Experience With Left Atrial Appendage Closure for Stroke Prevention in Atrial Fibrillation.

BACKGROUND: Left atrial appendage closure (LAAC) was approved by the U.S. Food and Drug Administration (FDA) as a stroke prevention alternative to warfarin for patients with nonvalvular atrial fibrillation. However, clinical decision-making is confounded by the fact that although LAAC attenuates the anticoagulant-related lifetime risk of bleeding, implantation is associated with upfront complications. Thus, enthusiasm for LAAC as a treatment option has been appropriately tempered, particularly as the therapy is introduced beyond the clinical trial sites into general clinical practice. OBJECTIVES: This study evaluated the acute procedural performance and complication rates for all cases performed in the United States since FDA approval. METHODS: In the absence of a formal national clinical registry since regulatory approval in March 2015, we obtained procedural data on implantation procedures. Every LAAC procedure requires the presence of a manufacturer clinical specialist and for procedural parameter and periprocedural complication data to be collected using a standardized process and forms. RESULTS: In 3,822 consecutive cases, implantation was successful in 3,653 (95.6%), with a median procedure time of 50 min (range 10 to 210 min). Implanting physicians performing these procedures (n = 382) included 71% new, nonclinical trial implanters, who performed 50% of the procedures. Procedural complication rates included 39 pericardial tamponades (1.02%) (24 treated percutaneously, 12 surgically, and 3 fatal); 3 procedure-related strokes (0.078%); 9 device embolizations (0.24%) (6 requiring surgical removal); and 3 procedure-related deaths (0.078%). CONCLUSIONS: Despite a large fraction of previously inexperienced operators, in the real-world post-FDA approval experience of LAAC, procedural success was high and complication rates were low.

Cryotherapy increases features of plaque stability in atherosclerotic rabbits.

AIMS: In the last 10 years, cryotherapy has been investigated as a new technology to treat vascular disease. The efficiency of cryotherapy in stabilising atherosclerotic plaques has never been described. The purpose of the present study was to evaluate the effect of catheter-based cryotherapy on atherosclerotic plaque composition in a rabbit model of atherosclerosis. METHODS AND RESULTS: Twenty-four New Zealand white rabbits were fed a 0.3% cholesterol-supplemented diet for 24 weeks. At two predefined sites of the atherosclerotic thoracic aorta, catheter-based cryotherapy, applying either single-dose, double-dose cryotherapy or control inflation, was performed after randomisation. Rabbits were continued on a cholesterol-supplemented diet for one day (acute) or four weeks (chronic). One day after cryotherapy, apoptotic cell death of smooth muscle cells (SMCs) and endothelial cells (ECs) was observed, whereas macrophages were unaffected. Four weeks later, the amount of SMCs was restored, the EC layer was regenerated, and a subendothelial macrophage-free layer was formed, indicative of a more stable plaque. In addition, both the thickness and the type I collagen content of the fibrous cap were increased. CONCLUSIONS: The present study demonstrated that cryotherapy is feasible and appears to stabilise atherosclerotic plaques in a rabbit model.