Stephanie Sellers

University of British Columbia | UBC · Division of Cardiology

Background: Transcatheter aortic valve implantation (TAVI) is now a well-established therapeutic option in an elderly high-risk patient cohort with aortic valve disease. Although most commonly performed via a transfemoral route, alternative approaches for TAVI are constantly being improved. Instead of the classical mini-sternotomy, it is possible...

Background: When a balloon-expandable transcatheter heart valve (THV) is chosen to treat a failed balloon-expandable THV, there is a risk of underexpansion with a potential impact on performance. Aims: We aimed to assess the impact of pre- and post-dilatation on the expansion of balloon-expandable THVs after redo-transcatheter aortic valve impla...

Background: With growing adoption of coronary computed tomographic angiography (CTA), there is increasing evidence for and interest in the prognostic importance of atherosclerotic plaque volume. Manual tools for plaque segmentation are cumbersome, and their routine implementation in clinical practice is limited. Objectives: The aim of this study...

Background: Preprocedural computed tomography (CT) workup with assessment of virtual transcatheter heart valve-to-coronary ostia (VTC) distance and transcatheter heart valve-to-sinus (VTS) distances is recommended to assess the risk of coronary obstruction following valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR). Objectives:...

Transcatheter aortic valve replacement (TAVR) in patients with bicuspid aortic valve disease (BAV) has potential risks of under expansion and non-circularity which may compromise long-term durability. This study aims to investigate calcium fracture and balloon over expansion in balloon-expandable TAVs on the stent deformation with the aid of simula...

Background: Coronary obstruction and access are concerns in patients undergoing redo transcatheter aortic valve implantation (TAVI). Aims: We sought to assess the neo-skirt height, leaflet overhang, leaflet deflection,and transcatheter heart valve (THV) expansion and performance, at 2 different implant depths, of the SAPIEN 3 Ultra (S3U) within...

Background: Bioprosthetic valve fracture (BVF) can be used to improve transcatheter heart valve (THV) haemodynamics following a valve-in-valve (ViV) intervention. However, whether BVF should be performed before or after THV deployment and the implications on durability are unknown. Aims: We sought to assess the impact of BVF timing on long-term TH...

Introduction: Coronary CT Angiogram (CCTA) has become a powerful tool in the diagnosis and risk stratification of coronary artery disease (CAD), but can also provide unique insight into the effects of pharmacotherapy on the progression of atherosclerosis. Although Renin-Angiotensin-Aldosterone-System (RAAS) inhibitors are indicated in patients with...

Aim Myocardial infarction remains the leading cause of heart failure. The adult human heart lacks the capacity to undergo endogenous regeneration. New blood vessel growth is integral to regenerative medicine necessitating a comprehensive understanding of the pathways that regulate vascular regeneration. We sought to define the transcriptomic dynami...

Bioprosthetic valve dysfunction (BVD) and bioprosthetic valve failure (BVF) may be caused by structural or nonstructural valve dysfunction. Both surgical and transcatheter bioprosthetic valves have limited durability because of structural valve deterioration. The main objective of this summary of experts participating in a virtual workshop was to p...

In spite of the noninferiority of transcatheter aortic valve replacement (TAVR) in high- and intermediate-risk patients, there are still obstacles that need to be overcome before the procedure is further expanded and clinically integrated. The lack of evidence on the long-term durability of the bioprostheses used for TAVR remains of particular conc...

Objectives The authors sought to evaluate the impact of different transcatheter heart valve (THV) designs, neoskirt height, implant technique, and cell misalignment on coronary access after redo transcatheter aortic valve replacement (TAVR). Background The implications and potential challenges of coronary access after redo TAVR are unknown. Metho...

Background Limited evidence is available regarding valve-in-valve (VIV) intervention with the ACURATE neo transcatheter heart valve (THV). Low implantation has demonstrated leaflet interaction between the surgical bioprosthesis and the THV, leading to impaired hydrodynamic performance. It is unknown if commissural alignment (CA) can affect this phe...

Background: Patients with thoracic aortopathy are at increased risk of catastrophic aortic dissection, carrying with it substantial mortality and morbidity. Although granular medial calcinosis (medial microcalcification) has been associated with thoracic aortopathy, its relationship to disease severity has yet to be established. Methods: One hun...

Over the last two decades, transcatheter devices have been developed to repair or replace diseased mitral valves (MV). Transcatheter mitral valve repair (TMVr) devices have been proven to be efficient and safe, but many anatomical structures are not compatible with these technologies. The most significant advantage of transcatheter mitral valve rep...

Background MRI and fluorine 18-labeled sodium fluoride (18F-NaF) PET can be used to identify features of plaque instability, rupture, and disease activity, but large studies have not been performed. Purpose To evaluate the association between 18F-NaF activity and culprit carotid plaque in acute neurovascular syndrome. Materials and Methods In this...

Background Myocardial infarction (MI) is the leading cause of heart failure. The adult human heart, unlike mouse or early neonatal hearts, lacks the capability to undergo extensive regeneration. Rapid re-establishment of blood flow post MI is vital for limiting tissue damage and preserving cardiac function. A better understanding of the mechanisms...

PurposeFailure of transcatheter heart valves (THV) may potentially be treated with repeat transcatheter aortic valve implantation (redo TAVI). We assessed hydrodynamic performance, stability and pinwheeling utilizing the ALLEGRA (New Valve Technology, Hechingen, Germany) THV, a CE approved and marketed THV in Europe, inside different THVs.Methods R...

South Asians (SAs) experience a higher prevalence and earlier onset of coronary artery disease and have worse outcomes relative to White Caucasians (WCs) following invasive revascularization procedures, a mainstay of coronary artery disease (CAD) management. We sought to review the differences in the CAD pattern and risk factors between SA and WC p...

Purpose: In this cohort study, 5-year data from the Coronary CT Angiography Evaluation for Clinical Outcomes: An International Multicenter Registry (ie, CONFIRM) were examined to identify associations of baseline aspirin and statin use with mortality, major adverse cardiovascular events (MACE), and myocardial infarction (MI) in individuals without...

Background Transcatheter heart valve (THV) dysfunction with an elevated gradient or paravalvular leak (PVL) may be documented late after THV implantation. Medical management, paravalvular plugs, redo THV replacement, or surgical valve replacement may be considered. However, late balloon dilatation is rarely utilized because of concerns about safety...

Objectives Among patients with low to high coronary artery calcium (CAC) scores, our aims were to quantify co-occurring obstructive and nonobstructive noncalcified plaque and serial progression of atherosclerotic plaque volume. Background Among symptomatic patients, it remains unclear whether a CAC score alone is sufficient or misses a sizeable bu...

Objective To evaluate the flow dynamics of self-expanding and balloon expandable transcatheter aortic valves (TAV) pertaining to turbulence and pressure recovery. Transcatheter aortic valves are characterized by different designs that have different valve performance and outcomes. Methods Assessment of TAVs was performed using self-expanding devic...

Objectives In a proof-of-concept study, this investigation aimed to establish whether ¹⁸F-sodium fluoride (¹⁸F-NaF) positron emission tomography (PET) combined with computed tomography (CT) angiography could identify aortic medial disease activity in patients with acute aortic syndrome. Background Acute aortic syndrome is associated with aortic me...

Myocardial infarction remains the leading cause of heart failure. The adult human heart lacks the capacity to undergo endogenous regeneration. New blood vessel growth is integral to regenerative medicine necessitating a comprehensive understanding of the pathways that regulate vascular regeneration. We present a comprehensive meta-analysis of integ...

Objectives The aim of this study was to describe the potential of ¹⁸F-sodium fluoride (¹⁸F-NaF) positron emission tomography (PET) to identify graft vasculopathy and to investigate the influence of coronary artery bypass graft (CABG) surgery on native coronary artery disease activity and progression. Background As well as developing graft vasculop...

Objectives This study sought to determine the degree of Evolut (Medtronic) leaflet pinning, diameter expansion, leaflet overhang, and performance at different implant depths of the balloon-expandable Sapien 3 (S3, Edwards Lifesciences LLC) transcatheter heart valve (THV) within the Evolut THV. Background Preservation of coronary access and flow is...

Objectives Using a novel glycoprotein IIb/IIIa receptor radiotracer 18F-GP1, we investigated whether positron emission tomography (PET)-computed tomography (CT) could detect thrombus formation on bioprosthetic aortic valves. Background Bioprosthetic valve thrombosis may have implications for valve function and durability. Methods Ex vivo experime...

Patients with the complex congenital heart disease (CHD) are usually associated with right ventricular outflow tract dysfunction and typically require multiple surgical interventions during their lives to relieve the right ventricular outflow tract abnormality. Transcatheter pulmonary valve replacement was used as a non-surgical, less invasive alte...

Clinically used heart valve prostheses, despite their progress, are still associated with limitations. Biodegradable poly-ε-caprolactone (PCL) nanofiber scaffolds, as a matrix, were seeded with human endothelial colony-forming cells (ECFCs) and human induced-pluripotent stem cells-derived MSCs (iMSCs) for the generation of tissue-engineered heart v...

Aortic stenosis (AS) is the most common heart valve disease requiring surgery in developed countries, with a rising global burden associated with aging populations. The predominant cause of AS is believed to be driven by calcific degeneration of the aortic valve and a growing body of evidence suggests that platelets play a major role in this diseas...

Objectives The aim of this study was to evaluate flow dynamics in the aortic sinus and the neosinus (NS) after transcatheter heart valve (THV) implantation in valve-in-valve (ViV). Background Leaflet thrombosis may occur on THVs and affect performance and durability. Differences in flow dynamics may affect the risk for leaflet thrombosis. Methods...

Objectives: To obtain more powerful assessment of the prognostic value of fractional flow reserveCT testing we performed a systematic literature review and collaborative meta-analysis of studies that assessed clinical outcomes of CT-derived calculation of FFR (FFRCT) (HeartFlow) analysis in patients with stable coronary artery disease (CAD). Meth...

Background South Asians (SA) have an increased prevalence of coronary artery disease (CAD) and myocardial infarction compared with age- and sex-adjusted White Caucasians (WC). The mechanism for this increased risk is poorly understood. While classical CD14++CD16- monocytes act as independent predictors of cardiovascular disease, differences in the...

Objectives To investigate potential differences in plaque progression (PP) between in East Asians and Caucasians as well as to determine clinical predictors of PP in East Asians. Background Studies have demonstrated differences in cardiovascular risk factors as well as plaque burden and progression across different ethnic groups. Methods The stud...

BACKGROUND South Asians (SAs) have an increased prevalence of coronary artery disease (CAD) and myocardial infarction compared with age- and sex-adjusted White Caucasians (WCs). The mechanism for this increased risk is poorly understood. While classical CD14++CD16- monocytes act as independent predictors of cardiovascular disease, differences in th...

In the absence of disease impacting the coronary arteries or myocardium, there exists a linear relationship between vessel volume and myocardial mass to ensure balanced distribution of blood supply. This balance may be disturbed in diseases of either the coronary artery tree, the myocardium, or both. However, in contemporary evaluation the coronary...

As transcatheter aortic valve replacement (TAVR) expands into a younger and lower risk cohort of patients, many important clinical questions are raised, including the one of overall valve durability. Bioprosthetic valve dysfunction (BVD) is a complex clinical issue, of which structural valve deterioration (SVD) is a subcategory. Similar to surgical...

Background Posterolateral rotator instability (PLRI) is the most common pattern of recurrent elbow instability and current imaging to aid PLRI diagnosis is limited. Thus, we sought to define use of ultrasound (US) to determine normal lateral ulnohumeral joint measurements, with and without posterolateral drawer testing to provide an insight into ho...

Background: There remain major uncertainties regarding disease activity within the retained native aortic valve as well as bioprosthetic valve durability following transcatheter aortic valve implantation (TAVI). We aimed to assess native aortic valve disease activity and bioprosthetic valve durability in patients with TAVI in comparison to subjects...

Dysferlinopathies are a group of muscle disorders caused by mutations to dysferlin, a transmembrane protein involved in membrane patching events following physical damage to skeletal myofibers. We documented dysferlin expression in vascular tissues including non-muscle endothelial cells, suggesting that blood vessels may have an endogenous repair s...

Background Acute aortic syndrome is a catastrophic condition characterised by medial degeneration and cellular destruction within the aortic wall. 18F-Sodium fluoride (18F-NaF) positron emission tomography (PET) detects microscopic calcification as a marker of disease activity. This proof-of-concept study aims characterise 18F-NaF PET in patients w...

One of the most common acute and chronic cardiovascular disease conditions is aortic stenosis, a disease in which the aortic valve is damaged and can no longer function properly. Moreover, aortic stenosis commonly exists in combination with other conditions causing so many patients suffer from the most general and fundamentally challenging conditio...

Aims To investigate the change in atherosclerotic plaque volume in patients with chronic kidney disease (CKD) and declining renal function, using coronary computed tomography angiography (CCTA). Methods and results In total, 891 participants with analysable serial CCTA and available glomerular filtration rate (GFR, derived using Cockcroft–Gault f...

The association of obesity with cardiovascular disease is well established. However, the interplay of obesity and vascular dysfunction in peripheral tissues such as skeletal muscle, which plays a key in role metabolic homeostasis, requires further study. In particular, there is a paucity of data with regard to sex-differences. Therefore, using a mu...

Background: THV implantation within failed surgical valves is well established. However the implications of THV implantation within failed THVs is poorly understood. Aims: This study assessed the impact of different transcatheter heart valve (THV) designs and implant positioning strategies on hydrodynamic performance after redo transcatheter aor...

Early microcalcification is a feature of coronary plaques with an increased propensity to rupture and to cause acute coronary syndromes. In this ex vivo imaging study of coronary artery specimens, the non-invasive imaging radiotracer, ¹⁸F-fluoride, was highly selective for hydroxyapatite deposition in atherosclerotic coronary plaque. Specifically,...

Background 18F-GP1 is a novel radiotracer with a high affinity for the platelet glycoprotein IIb/IIIa receptor. Subclinical bioprosthetic valve thrombus has been postulated as a trigger for accelerated valve degeneration. Purpose To determine the feasibility of 18F-GP1 positron-emission tomography-computed tomography (PET-CT) for the detection of...

Objectives The aim of the current study was to explore the impact of plaque calcification in terms of absolute calcified plaque volume (CPV) and in the context of its percentage of the total plaque volume at a lesion and patient level on the progression of coronary artery disease. Background Coronary artery calcification is an established marker o...

Degeneration of surgical bioprosthetic heart valves (BPVs) occurs in up to one third of surviving patients within a decade of implantation and is a common cause of cardiovascular morbidity. Valve-in-valve transcatheter aortic valve replacement (VIV TAVR) is a safe and effective treatment for patients with failed BPVs who are unsuitable for reoperat...

Background Bioprosthetic valve fracture (BVF) improves residual transvalvular gradients following valve-in-valve (VIV) transcatheter aortic valve replacement (TAVR). The extent and composition of potential embolized debris from BVF are unknown. Methods BVF was performed in 4 previously explanted and fixed surgical bioprosthetic valves (BPVs) using...

Bioprosthetic valve thrombosis (BPVT) is a recognised complication of prosthetic aortic valves and can be found in up to 13% of patients after transcatheter implantation. The mechanism of BPVT is not well known, abnormal flow conditions in the new and native sinuses and lack of functional endothelialisation are suspected causes. BPVT may result in...

Introduction CT measurement of supra-annular area (SA) has been proposed as an alternative to annular area (AA) for sizing of trancatheter valves in biscuspid aortic valves (BAV). This study examines the reproducibility of SA and AA measurements and their potential impact on downstream transcatheter heart valve sizing and clinical outcomes. Method...

The treatment of severe symptomatic aortic stenosis has undergone a paradigm shift over the last decade, paralleling the publication of several landmark trials showing efficacy and safety of transcatheter aortic valve replacement (TAVR) as compared to traditional open surgical aortic valve replacement (SAVR) across multiple risk strata. Hypoattenua...

Introduction: With growing guideline support and clinical evidence, the demand for CCTA is increasing at a significant rate globally. With modest reimbursement in the US and limited resources in single payer systems, access to cardiac CT remains an issue. We aimed to assess the impact of a small footprint purpose built cardiac CT on access and the...