W.L. Yeow

Bio: W.L. Yeow is an academic researcher from Royal Perth Hospital. The author has contributed to research in topics: Aortic valve replacement & Valve replacement. The author has an hindex of 1, co-authored 1 publications receiving 6 citations.

Expanding role for transcatheter aortic valve replacement: successful transfemoral implantation of a Medtronic CoreValve for severe aortic regurgitation.

Abstract: Severe aortic regurgitation (AR), when intervention is required, is best managed by surgical aortic valve replacement (SAVR). Transcatheter aortic valve replacement (TAVR) for aortic stenosis has recently shown non-inferiority to SAVR and superiority to medical management. Here we describe a successful TAVR for a patient with severe AR that was unsuitable for SAVR due to her high surgical risk.

Transcatheter valve-in-valve implantation: a systematic review of literature.

Abstract: Introduction Transcatheter aortic valve implantation (TAVI) has become an alternative to open surgery in those deemed high risk. The purpose of this study was to evaluate the effectiveness and outcomes of this emerging procedure. We have examined available literature to provide an overview of valve-in-valve implantation using transcatheter heart valves (THVs) in aortic, mitral, pulmonary, tricuspid positions. Methods A systematic search was conducted using MEDLINE, PubMed, EMBASE, Current Contents Connect, Cochrane library, Google Scholar, Science Direct, and Web of Science. Results Only 61 studies met full criteria and were included the review. This included 31 studies reporting transcatheter aortic valve-in-valve implantation, mitral valve-in-valve implantation (13 studies), tricuspid valve-in-valve implantation (12 studies), and pure native aortic valve regurgitation (nine studies). One of the limitations of this review is that most of the studies included were case reports, together with some case series. Conclusion Valve-in-valve implantation can be considered as an acceptable alternative to conventional open heart surgery for elderly high-risk surgical patients with bioprosthetic degeneration. Long-term follow-up of treated patients will be necessary to establish the true role of valve-in-valve implantation for bioprosthetic degeneration. Patients should be evaluated on an individual basis until outcomes are proven in large cohort studies or randomised trials.

Transcatheter aortic valve replacement for native aortic valve regurgitation as a bridge to liver transplantation.

Abstract: Coexistence of end-stage liver disease (ESLD) and severe valvular heart disease conveyed substantial risk for patients, oftentimes leading to exclusion from liver transplantation candidacy due to inability to safely offer cardiac surgery prior to transplantation. Several approaches have been described, including performing transplantation and valve surgery concurrently, or in sequence. Both options, however, have associated complications: catastrophic repercussion of peri-operative coagulopathy and organ dysfunction post-transplantation, respectively. The introduction of transcatheter procedures offered a safer alternative for high-risk patients; however, its recognized indications remained limited. A novel approach to this surgical dilemma by performing transcatheter aortic valve replacement (TAVR) for severe native aortic valve regurgitation in a patient on the liver transplant list has been presented. The procedure proved to be an effective management for the aortic valve insufficiency, improving our patient's hemodynamics in preparation for the subsequent orthotopic liver transplantation (OLT). © 2015 Wiley Periodicals, Inc.

Transcatheter Aortic Valve Implantation (TAVI) for Native Aortic Valve Regurgitation - A Systematic Review.

Abstract: Background Transcatheter aortic valve implantation (TAVI) has become the standard of care for management of high-risk patients with aortic stenosis. Limited data is available regarding the performance of TAVI in patients with native aortic valve regurgitation (NAVR).Methods and Results:We performed a systematic review from 2002 to 2016. The primary outcome was device success as per VARC-2 criteria. Secondary endpoints included procedural complications, and 30-day and 1-year mortality rates. A total of 175 patients were included from 31 studies. Device success was reported in 86.3% of patients - with device failure driven by moderate aortic regurgitation (AR ≥3+) and/or need for a second device. Procedural complications were rare, with no procedural deaths, myocardial infarctions or annular ruptures reported. Procedural safety was acceptable with a low 30-day incidence of stroke (1.5%). The 30-day and 1-year overall mortality rates were 9.6% and 20.0% (cardiovascular death, 3.8% and 10.1%, respectively). Patients receiving 2nd-generation valves demonstrated similar safety profiles with greater device success compared with 1st-generation valves (96.2% vs. 78.4%). This was driven by the higher incidence of second-valve implantation (23.4% vs. 1.7%) and significant paravalvular leak (8.3% vs. 0.0%). Conclusions TAVI demonstrates acceptable safety and efficacy in high-risk patients with severe NAVR. Second-generation valves may afford a similar safety profile with improved device success. Dedicated studies are needed to definitively establish the efficacy of TAVI in this population.

"Valve in valve" implantation of two self-expandable transcatheter aortic valves in a patient with aortic root aneurysm and massive aortic regurgitation: "a new TAVI option".

Abstract: Catheter-based treatment of aortic regurgitation (AR) often proves challenging especially due to associated anatomical difficulties. Here, we present a case of CoreValve implantation with a novel use of the valve-in-valve technique to effectively treat severe AR in a patient with repeated cardiac surgery and aneurismatic prosthetic ascending aorta. © 2013 Wiley Periodicals, Inc.

Transcatheter Aortic Valve Replacement: What the Near-Term Future Holds and What Evidence Is Needed?

Abstract: Transcatheter aortic valve replacement (TAVR) is a rapidly evolving therapy that already has a strong evidence base in both inoperable and high-risk patients with severe calcific aortic stenosis. Its ongoing growth as a treatment modality in the near future demands a rigorous approach to clinical research to provide evidence to support its long-term safety and efficacy. This evidence will come in several important areas: (1) refining the indications for TAVR, (2) improving its safety, and (3) building on the success of the first-generation devices with novel designs and concepts. The indications for this technology are being refined, and although the primary focus is on aortic stenosis, exciting new applications are emerging that will require rigorous evaluation and present new challenges. Improving the safety and efficacy of TAVR is of paramount importance, and there is a growing evidence base that concurrent advances in imaging techniques are helping to reduce complications that can arise with TAVR. Several new TAVR devices are emerging, which are each being evaluated in clinical studies.