Alexander B Willson

Joondalup Health Campus · Cardiology

Background Current imaging techniques may inadequately rule out coronary artery obstruction (CAO), a potentially fatal complication during transcatheter aortic valve replacement (TAVR). Advancements in three-dimensional (3D)-printing allow the development of models capable of replicating cardiac anatomy and predicting CAO. We sought to simulate TAV...

Background: Shorter door to balloon times are associated with improved outcomes in patients suffering from ST-elevation myocardial infarctions (STEMI). To determine whether prehospital activation of a new regional Australian cardiac catheterisation Laboratory (CCL) reduced pain to balloon time (PTBT), first medical contact to balloon time (FMCTBT),...

Computed tomography (CT) has an increasingly important role in transcatheter aortic valve replacement (TAVR), offering noninvasive three-dimensional measurements of the aortic annulus which are used for transcatheter heart valve (THV) sizing. Accurate valve sizing is vital to reduce the risk of complications with TAVR, particular paravalvular aorti...

Introduction: ST-Elevation myocardial infarction (STEMI) is associated with significant mortality with primary percutaneous intervention (PCI) being the standard of care. Shorter door to balloon times is associated with reduced mortality. Additionally, delay in hospital presentation from the time of onset of chest pain and self presenting to hospit...

In transcatheter aortic valve replacement, prosthesis oversizing is essential to prevent paravalvular regurgitation. However, the estimated extent of oversizing strongly depends on the measurement used for annular sizing. The aim was to investigate the influence of geometrical parameters for calculation of relative oversizing in transcatheter aorti...

Prosthesis-patient mismatch (PPM) is a predictor of mortality after aortic valve replacement (AVR). We examined whether accurate 3-dimensional annular sizing with multidetector CT (MDCT) is predictive of PPM after transcatheter AVR (TAVR). One hundred twenty-eight patients underwent MDCT then TAVR. Moderate PPM was defined as an indexed effective o...

Objectives: This study prospectively investigated the impact of integration of a multidetector computed tomography (MDCT) annular area sizing algorithm on transcatheter aortic valve replacement (TAVR) outcomes. Background: Appreciation of the 3-dimensional, noncircular geometry of the aortic annulus is important for transcatheter heart valve (TH...

OBJECTIVES: This report sought to study the impact of the balloon-expandable SAPIEN XT (Edwards Lifesciences, Irvine, California) transcatheter heart valve (THV) stent frame geometry and position on outcomes of transcatheter aortic valve replacement (TAVR). BACKGROUND: Post-implant THV geometry and position might impact atrioventricular conduction,...

The aim of this study was to demonstrate the first-in-human feasibility and short-term clinical outcomes with a new balloon-expandable transcatheter heart valve (THV). The SAPIEN 3 (S3) THV incorporates a paravalvular sealing system, an active 3-dimensional coaxial positioning catheter, and is compatible with a 14-F expandable sheath. The S3 THV wa...

The aim of this study was to demonstrate feasibility and short- and midterm clinical outcomes with a new self-expanding transcatheter heart valve and motorized delivery system. Refining transcatheter aortic valve replacement with newly designed bioprostheses and delivery systems is anticipated to facilitate the procedure, reduce the risk of complic...

Background: Computed tomography (CT) annular measurements are predictive of paravalvular regurgitation after transcatheter aortic valve replacement (TAVR) which is a predictor of mortality and morbidity. Objectives: To demonstrate the rationale and potential implications of new CT sizing recommendations for TAVR. Methods: The CT sizing recomme...

Objectives To demonstrate the feasibility of transfemoral transcatheter aortic valve replacement (TAVR) with the 29 mm Edwards SAPIEN XT valve and Novaflex + delivery system through a 20F expandable sheath (eSheath, Edwards Lifesciences, USA). In addition, to describe the use of the Novaflex + delivery system and expandable sheath. BackgroundTAVR h...

The aim of this study was to examine sex differences in outcome after transcatheter aortic valve replacement (TAVR) with real-world data from 2 large centers in Canada. Transcatheter aortic valve replacement is an effective alternative to surgical valve replacement in symptomatic patients with severe aortic stenosis, but the impact of sex on outcom...

The purpose of this study was to demonstrate the feasibility and procedural outcomes with a new self-expanding and repositionable transcatheter heart valve. Transcatheter aortic valve replacement is a viable option for selected patients with severe symptomatic aortic stenosis. However, suboptimal prosthesis positioning may contribute to paravalvula...

This study sought to evaluate the structural integrity of balloon-expandable stents used in transcatheter aortic valve replacement. Underexpansion, deformation, or fracture of stent frames may affect transcatheter heart valve (THV) function and durability. Patients >1 year after transcatheter aortic valve replacement underwent multidetector compute...

This study sought to evaluate outcomes after implantation of a second transcatheter heart valve (THV-in-THV) for acute THV failure. Aortic regurgitation after transcatheter aortic valve replacement (TAVR) may be valvular due to prosthetic leaflet dysfunction or paravalvular due to poor annular sealing. Patients undergoing aortic balloon-expandable...

Identifying the optimal fluoroscopic projection of the aortic valve is important for successful transcatheter aortic valve replacement (TAVR). Various imaging modalities, including multidetector computed tomography (MDCT), have been proposed for prediction of the optimal deployment projection. We evaluated a method that provides 3-dimensional angio...

The aim of this study was to evaluate the impact of mitral regurgitation (MR) on outcomes after transcatheter aortic valve replacement (TAVR) and the impact of TAVR on MR. Little is known of the influence of MR on outcomes after TAVR. The outcomes of patients with mild or less (n = 319), moderate (n = 89), and severe (n = 43) MR were evaluated afte...

This study sought to analyze multidetector computed tomography (MDCT) 3-dimensional aortic annular dimensions for the prediction of paravalvular aortic regurgitation (PAR) following transcatheter aortic valve replacement (TAVR). Moderate or severe PAR after TAVR is associated with increased morbidity and mortality. A total of 109 consecutive patien...

The aim of this study was to evaluate vascular complications in a consecutive patient population undergoing transfemoral percutaneous aortic valve replacement (PAVR) applying current Valve Academic Research Consortium definitions. Vascular complications have been the major cause of mortality and morbidity associated with PAVR. Both open surgical an...

When bioprosthetic cardiac valves fail, reoperative valve replacement carries a higher risk of morbidity and mortality compared with initial valve replacement. Transcatheter heart valve implantation may be a viable alternative to surgical aortic valve replacement for high-risk patients with native aortic stenosis, and valve-in-valve (V-in-V) implan...

This study sought to determine the most reproducible multidetector computed tomography (MDCT) measurements of the aortic annulus and to determine methods to improve the applicability of these measurements for transcatheter aortic valve implantation. The reproducibility and applicability of MDCT annular measurements to guide transcatheter aortic val...

There is heterogeneity in the reporting of procedural outcomes and complications following transcatheter aortic valve replacement (TAVR). Recently, new definitions have been proposed by the Valve Academic Research Consortium (VARC) in an effort to standardise these outcomes and improve the quality of future clinical research. The aim of this study...

Transcatheter aortic valve replacement (TAVR) has become an attractive alternative for patients with severe aortic stenosis at high surgical risk. We describe a step-by-step approach to performing TAVR with the SAPIEN XT valve.

Transcatheter aortic valve implantation (TAVI) for the management of symptomatic aortic stenosis has evolved rapidly over the last ten years, to the point where TAVI has recently been established as the standard of care for inoperable patients. With the results of further trials, steady improvements in device design and a greater understanding, it...

To assess whether a collaborative interdepartmental pathway involving emergency department (ED) physicians activating the cardiac catheterisation laboratory (CCL) with immediate patient transfer to the CCL reduces door-to-balloon (DTB) times for patients with suspected ST-elevation myocardial infarction (STEMI). A quasi-experimental before-and-afte...