The evolving role of transcatheter aortic valve implantation computed tomography in coronary artery assessment: a deeper dive into efficiency, challenges, and future perspectives.
The evolving role of transcatheter aortic valve implantation computed tomography in coronary artery assessment: a deeper dive into efficiency, challenges, and future perspectives.
Project description:The rapid expansion of transcatheter aortic valve implantation (TAVI) has been based upon robust clinical evidence derived from randomized controlled trials and large-scale international and national registries. Over the past decade, TAVI has evolved into a safe and effective procedure with predictable and reproducible outcomes. As a consequence, the TAVI technology is increasingly used to treat patients with a lower risk profile and the volume of TAVI now exceeds surgical aortic valve replacement (SAVR) in some countries. It may be anticipated that, in the near future, the majority of patients with severe symptomatic aortic valve stenosis will undergo TAVI as first line therapy, regardless of their age and risk profile. This article identifies some of the specific challenges that lie ahead when considering expansion of TAVI to younger patients.
Project description:Background: The outcome of redo transcatheter aortic valve (TAV) implantation (TAVI) is unknown for TAV structural valve degeneration (SVD). This paper reports the initial results of redo TAVI for TAV-SVD in Japanese patients. Methods and Results: Of 630 consecutive patients, 6 (1.0%) underwent redo TAVI for TAV-SVD (689-1,932 days after the first TAVI). The first TAV were 23-mm balloon-expandable valves (BEV, n=5) and a 26-mm self-expandable valve (SEV, n=1). All patients underwent multidetector computed tomography (MDCT) before redo TAVI, which showed first-TAV under-expansion (range, 19.1-21.0 mm) compared with the label size. Two BEV and 4 SEV were successfully implanted as second TAV, without moderate/severe regurgitation or 30-day mortality. One of 2 patients with a BEV-inside-BEV implantation had a high transvalvular mean pressure gradient post-procedurally (34 mmHg) and required surgical valve replacement 248 days after the redo TAVI. This, however, was unnoted in patients with SEV implantation during redo TAVI. Planned coronary artery bypass grafting was concomitantly performed in 1 patient with a small sino-tubular junction and SEV-inside-SEV implantation because of the risk of coronary malperfusion caused by the first TAV leaflets. Five of the 6 patients survived during the follow-up period (range, 285-1,503 days). Conclusions: Redo TAVI for TAV-SVD appears safe and feasible, while specific strategies based on MDCT and device selection seem important for better outcomes.
Project description:ObjectiveTranscatheter aortic valve implantation (TAVI) procedures are increasing rapidly, but the durability of tissue valve and periprocedural complications are not satisfactory. Immune reaction to the galactose-α-1,3 galactose β-1,4-N-acetylglucosamine (α-Gal) and conventional processing protocols of cardiac xenografts lead to calcification. Next-generation TAVI needs to be made with α-Gal-free xenografts by multiple anticalcification therapies to avoid immune rejection and enhance durability, and three-dimensional (3D) printing technology to improve the procedural safety.MethodsPorcine pericardia were decellularized and immunologically modified with α-galactosidase. The pericardia were treated by space filler, crosslinked with glutaraldehyde in organic solvent, and detoxified. The sheep-specific nitinol (nickel-titanium memory alloy) wire backbone was made from a 3D-printed model for ovine aortic root. After it passed the fitting test, we manufactured a self-expandable stented valve with the porcine pericardia mounted on the customized nitinol wire-based stent. After in vitro circulation using customized silicone aortic root, we performed TAVI in 9 sheep and obtained hemodynamic, radiological, immunohistopathological, and biochemical results.ResultsThe valve functioned well, with excellent stent fitting and good coronary flow under in vitro circulation. Sheep were sequentially scheduled to be humanely killed until 238 days after TAVI. Echocardiography and cardiac catheterization demonstrated good hemodynamic status and function of the aortic valve. The xenografts were well preserved without α-Gal immune reaction or calcification based on the immunological, radiographic, microscopic, and biochemical examinations.ConclusionsWe proved preclinical safety and efficacy for next-generation α-Gal-free TAVI with multiple anticalcification therapies and 3D-printing technology. A future clinical study is warranted based on these promising preclinical results.
Project description:Transcatheter aortic valve implantation (TAVI) has emerged as the gold standard technique for all patients with symptomatic severe aortic stenosis at elevated surgical risk. Much progress has been made to reduce procedural complications and improve patient outcomes. The impressive results of contemporary TAVI can be attributed to a variety of factors, including improving operator experience, pre-operative patient screening, and developments in transcatheter heart valve and delivery system technology. Despite these advances, serious procedural complications continue to occur and there remain some anatomical subsets and patient groups to whom TAVI technology has not been expanded. Herein we discuss these unmet needs in TAVI.
Project description:BackgroundIncreasing demand for transcatheter aortic valve implantation (TAVI) places greater emphasis on the efficiency of pathways and services. A significant limitation to increasing TAVI capacity is the availability of cardiac catheterisation laboratory time. We have developed a novel complexity scoring system (TAVI ComplEXity; TEX score) which can aid in planning lists with appropriate case selection. To validate the TEX score, we have undertaken a retrospective analysis of TAVI cases. The hypothesis is that increasing TEX score correlates with increased procedural duration and reduced valve academic research consortium (VARC) 3 technical and device success.MethodsThe TEX score assigns patients to a complexity level of 1 (low), 2 (intermediate) or 3 (high) based on the presence of specific clinical and anatomical variables. For validation purposes, comparisons were made between patients in the three complexity levels with respect to procedural duration as well as VARC-3 technical success, device success and early safety.ResultsThe validation study included 1034 consecutive patients who underwent TAVI between June 2021 and October 2023. Of these, 582 (56.3%) were classified as level 1 complexity, 377 (36.5%) level 2 and 75 (7.3%) level 3. Significant differences were observed between the three groups with respect to procedural duration (73.7 min vs 85.6 min vs 136 min; p<0.001), VARC-3 technical success (97.9% vs 96.6% vs 92%; p<0.05) and VARC-3 device success (96.2% vs 92.3% vs 86.6%; p<0.001).ConclusionThe TEX score is a simple tool which allows stratification of patients into three levels of complexity. Increasing complexity levels correlate with increasing procedural duration and reduced VARC-3 technical and device success. This is potentially useful for scheduling patients onto appropriate lists.
Project description:The use of transcatheter aortic valve implantation (TAVI) to treat severe symptomatic aortic valve stenosis has increased exponentially in the last decade. This rapid expansion was seen predominantly in Western developed nations and has been fuelled by favorable results reported from a plethora of well-publicized randomized controlled trials, large retrospective series and national registries. Now, TAVI has become the standard of care for inoperable patients and an alternative to open surgery in patients who are at intermediate to high risk for open surgery. Notwithstanding these positive results, Asia has been relatively slow to adopt this technology despite a potentially large patient pool. Unique features of Asian medical environments and differences in Asian anatomy affecting TAVI uptake in Asia will be discussed. This article serves to outline the various challenging aspects of disseminating TAVI in Asian countries.
Project description:BackgroundTranscatheter aortic valve implantation is safe and effective for high-risk patients with bioprosthetic valve failure (BVF) but has not been studied in low- and intermediate-risk patients. One year outcomes of the PARTNER 3 Aortic Valve-in-valve (AViV) Study were evaluated.MethodsThis prospective, single-arm, multicenter study enrolled 100 patients from 29 sites with surgical BVF. The primary endpoint was a composite of all-cause mortality and stroke at 1 year. The key secondary outcomes included mean gradient, functional capacity, and rehospitalization (valve-related, procedure-related, or heart failure related).ResultsA total of 97 patients underwent AViV with a balloon-expandable valve from 2017 to 2019. Patients were 79.4% male with a mean age of 67.1 years and Society of Thoracic Surgeons score of 2.9%. The primary endpoint occurred in 2 patients (2.1%) who had strokes; there was no mortality at 1 year. Five patients (5.2%) had valve thrombosis events, and 9 patients (9.3%) had rehospitalizations, including 2 (2.1%) for strokes, 1 (1.0%) for heart failure, and 6 (6.2%) for aortic valve reinterventions (3 explants, 3 balloon dilations, and 1 percutaneous paravalvular regurgitation closure). From baseline to 1 year, New York Heart Association class III/IV decreased from 43.3% to 4.5%, mean gradient from 39.1 ± 18.2 mm Hg to 19.7 ± 7.6 mm Hg, and ≥moderate aortic regurgitation from 41.1% to 1.1%.ConclusionsAViV with a balloon-expandable valve improved hemodynamic and functional status at 1 year and can provide an additional therapeutic option in selected low- or intermediate-risk patients with surgical BVF, although longer term follow-up is necessary.
Project description:BackgroundValve-in-valve transcatheter aortic valve implantation (TAVI) has emerged as a competent alternative for the treatment of degenerated bioprosthetic valves after surgical aortic valve replacement, or during TAVI procedure as a bailout option. Herein, we report a rare case of a self-expandable Medtronic Evolut R valve into a failing Medtronic CoreValve, with the use of modern pre-TAVI imaging screening, suggesting the proper procedural design steps for so complicated implantations.Case summaryA frail 78-year-old woman with a degenerated Medtronic Core Valve 26 mm bioprosthesis, implanted in 2011 due to severe aortic stenosis, was referred to our hospital due to worsening dyspnoea New York Heart Association III. The screening echocardiography documented severe aortic stenosis, while the classical risk scores were in favour of repeated TAVI (EuroSCORE II 5.67%). Computed tomography measurements and three-dimensional (3D) printing model were of great help for the proper valve selection (Medtronic Evolut R 26 mm), while the use of cerebral protection device (Claret Sentinel) was considered as a necessary part of the procedure. The simultaneous use of fluoroscopy and transoesophageal echocardiogram led to optimal haemodynamic result, confirmed by the discharge echocardiogram, with a significant clinical improvement during the first month follow-up.DiscussionThe main periprocedural concerns remain valve malpositioning, coronary artery obstruction, and high remaining transvalvular gradients. The multimodality pre-TAVI imaging screening may be helpful for precise procedural design. Despite the limited use of 3D models, it is necessary to adopt such tissue-mimicking phantoms to increase the possibility of optimal procedural result.
Project description:Transcatheter aortic valve implantation (TAVI), an established treatment for inoperable and high-risk operable symptomatic patients with severe aortic stenosis with growing numbers of procedures and expanding indications, is an expensive therapy. Cost-effectiveness analyses rely on the value of the incremental cost-effectiveness ratio (ICER), which is the difference in cost between two possible interventions, divided by the difference in their effect. Several analyses have demonstrated that TAVI is cost-effective with an acceptable ICER for the inoperable patient alone and only via the iliofemoral route, while TAVI is more costly and is either less or equally effective as surgery in high-risk operable patients. When use of TAVI is extended to include a larger number of patients suitable for surgery, the overall results become less favorable. Acceptable ICERs should practically equate to the value of the gross domestic product (GDP) per capita in each country; however, the cost of the TAVI kit alone already exceeds the GDP per capita of all moderate- and low-income countries. An overview of the current cost-efficacy issues of TAVI is presented and this grisly reality is discussed, which may hopefully be improved in the future.