Peter Barlis

Peter Barlis
University of Melbourne | MSD · Melbourne Medical School

MBBS, MPH, PhD, FESC, FCSANZ, FACC, FSCAI, FRACP

About

213
Publications
20,560
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
5,296
Citations
Additional affiliations
January 2013 - present
St. Vincent's Hospital Melbourne
Position
  • Cardiologist
February 2012 - present
University of Melbourne
Position
  • Honorary Principal Fellow
April 2011 - present
St. Vincent's Hospital Melbourne
Position
  • Interventional Cardiologist

Publications

Publications (213)
Article
Background: Lipid-rich plaque (LRP) is thought to be a precursor to cardiac events. However, its clinical significance in coronary arteries has never been systematically investigated. Objectives: This study investigated the prevalence and clinical significance of LRP in the nonculprit region of the target vessel in patients undergoing percutaneo...
Article
A 3.0 × 18 mm Absorb bioresorbable vascular scaffold (Abbott Vascular, Santa Clara, California) was implanted in the midsegment of the left anterior descending coronary artery of a patient with stable angina pectoris. Optical coherence tomography was performed following scaffold implantation (
Article
Coronary plaque rupture is the most common cause of vessel thrombosis and acute coronary syndrome. The accurate early detection of plaques prone to rupture may allow prospective, preventative treatment; however, current diagnostic methods remain inadequate to detect these lesions. Established imaging features indicating vulnerability do not confer...
Article
Percutaneous coronary intervention (PCI) has shown a high success rate in the treatment of coronary artery disease. The decision to perform PCI often relies on the cardiologist's visual interpretation of coronary lesions during angiography. This has inherent limitations, particularly due to the low resolution and two-dimensional nature of angiograp...
Article
Blockages within arteries, called stenoses, are a common cause of coronary artery disease (CAD). Stenosis is a result of atherosclerotic plaque build-up limits blood flow and hence oxygen and nutrient supplies. Past studies on stenosed arterial flows often assumed stenosis to be axisymmetric in shape. However, medical imaging modalities have shown...
Article
Full-text available
Patient-specific coronary endothelial shear stress (ESS) calculations using Newtonian and non-Newtonian rheological models were performed to assess whether the common assumption of Newtonian blood behavior offers similar results to a more realistic but computationally expensive non-Newtonian model. 16 coronary arteries (from 16 patients) were recon...
Article
Background Local hemodynamics are known to play an important role in the development of plaque erosion. Recent studies showed that erosion patients might be treated conservatively without stent implantation. We investigated evolution of hemodynamic parameters on the plaque erosion site in conservatively treated patients. Methods Computational flui...
Article
Full-text available
Troponin has been the cornerstone of the definition of MI since its introduction to clinical practice. High-sensitivity troponin has allowed clinicians to detect degrees of myocardial damage at orders of magnitude smaller than previously and is challenging the definitions of MI, with implications for patient management and prognosis. Detection and...
Article
Objectives: This study aimed to investigate the impact of mechanical factors at baseline on the patency of a restorative conduit for coronary bypass grafts in an ovine model at serial follow-up up to 1 year. Methods: The analyses of 4 mechanical factors [i.e. bending angle, superficial wall strain and minimum and maximum endothelial shear stress...
Article
The development of optical coherence tomography (OCT) has revolutionized our understanding of coronary artery disease. In vivo OCT research has paralleled with advances in computational fluid dynamics, providing additional insights in the various hemodynamic factors influencing plaque growth and stability. Recent OCT studies introduced a new concep...
Article
Full-text available
A novel method for four-dimensional superficial wall strain and stress (4D-SWS) is derived from the arterial motion as pictured by invasive coronary angiography. Compared with the conventional finite element analysis of cardiovascular biomechanics using the estimated pulsatile pressure, the 4D-SWS approach can calculate the dynamic mechanical state...
Article
Full-text available
Modern technologies and methods such as computer simulation, so-called in silico methods, foster the development of medical devices. For accelerating the uptake of computer simulations and to increase credibility and reliability the U.S. Food and Drug Administration organized an inter-laboratory round robin study of a generic nozzle geometry. In pr...
Article
Aims To investigate local haemodynamics in the setting of acute coronary plaque rupture and erosion. Methods and results Intracoronary optical coherence tomography performed in 37 patients with acute coronary syndromes caused by plaque rupture (n = 19) or plaque erosion (n = 18) was used for three-dimensional reconstruction and computational fluid...
Article
Backgrounds Data on optimal antiplatelet therapy in patients undergoing stenting of the proximal left anterior descending artery (LAD) are limited. Methods This is a post-hoc analysis of the GLOBAL LEADERS trial, a prospective, multi-center, randomized controlled trial, comparing the experimental strategy (1-month dual anti-platelet therapy [DAPT]...
Article
Full-text available
Importance Women experience worse ischemic and bleeding outcomes after percutaneous coronary intervention (PCI). Objectives To assess the association of sex with patient outcomes at 2 years after contemporary PCI and with the efficacy and safety of 2 antiplatelet strategies. Design, Setting, and Analysis This study is a prespecified subgroup anal...
Article
Background Local haemodynamic disturbances in coronary blood flow are associated with abnormal endothelial shear stress (ESS) and progressive atherosclerosis. However, standard techniques to estimate ESS lack the diagnostic specificity necessary for future clinical utility. Possible improvements include use of a more realistic non-Newtonian model o...
Article
Background Although blood is a non-Newtonian fluid, most clinical computational fluid dynamic (CFD) studies assume blood to be a Newtonian fluid with constant viscosity. At higher blood flow rates in larger arteries, the two models should present similar results, and the Newtonian assumption can be considered acceptable. However, whether the Newton...
Article
Background Despite being a shear-thinning non-Newtonian fluid, most computational fluid dynamic (CFD) simulations assume blood to be a Newtonian fluid with constant viscosity. The use of more realistic assumptions may deepen mechanistic understanding of the relationship between blood flow disturbances and atherosclerosis, and improve the diagnostic...
Article
Full-text available
The aim of this manuscript is to provide guidelines for appropriate use of CFD to obtain reproducible and reliable wall shear stress maps in native and instrumented human coronary arteries. The outcome of CFD heavily depends on the quality of the input data, which include vessel geometrical data, proper boundary conditions, and material models. Ava...
Article
Full-text available
Abstract Cardiac events are commonly triggered by rupture of intracoronary plaque. Many studies have suggested that retinal small vessel abnormalities predict cardiac events. The present study examined retinal microvascular abnormalities associated with intracoronary plaque. This was a single centre cross-sectional observational study of consecutiv...
Article
Full-text available
Incomplete stent apposition (ISA) is one of the causes leading to poststent complications, which can be found when an undersized or an underexpanded stent is deployed at lesions. The previous research efforts have focused on ISA in idealized coronary arterial geometry with circular cross section. However, arterial cross section eccentricity plays a...
Article
Background: We hypothesised that ticagrelor, in combination with aspirin for 1 month, followed by ticagrelor alone, improves outcomes after percutaneous coronary intervention compared with standard antiplatelet regimens. Methods: GLOBAL LEADERS was a randomised, open-label superiority trial at 130 sites in 18 countries. Patients undergoing percu...
Article
Full-text available
Chest pain and troponin elevation may be due to an acute coronary syndrome, myocarditis, acute cardiomyopathy, or other less common conditions. Management differs depending on the aetiology, and the pathophysiologic diagnosis has direct implications on treatment and patient outcomes. History and clinical examination is supplemented by selected inve...
Article
Aims: To evaluate the effect of strut protrusion(SP) on wall shear stress(WSS) and neointimal growth(NG) one and five-year after implantation of Absorb bioresorbable vascular scaffold. Methods and results: Eight patients were selected from the first-in-man study.Following three-dimensional(3D) reconstruction of the coronaries, WSS was quantified...
Article
Full-text available
Epidemiological studies suggest retinal microvascular abnormalities predict cardiac events. This study examined microvascular features associated with coronary artery abnormalities. This was a single-centre, cross-sectional, observational study of 144 consecutive subjects undergoing coronary angiography for clinical indications. Their angiograms we...
Article
One particular complexity of coronary artery is the natural tapering of the vessel with proximal segments having larger caliber and distal tapering as the vessel get smaller. The natural tapering of a coronary artery often leads to proximal incomplete stent apposition (ISA). ISA alters coronary hemodynamics and creates pathological path to develop...
Article
Full-text available
Aims: As a sine qua non for arterial wall physiology, local hemodynamic forces such as endothelial shear stress (ESS) may influence long-term vessel changes as bioabsorbable scaffolds dissolve. The aim of this study was to perform serial computational fluid dynamic (CFD) simulations to examine immediate and long-term haemodynamic and vascular chan...
Article
In this review, the authors explore the evolving evidence linking physiological assessment of coronary artery disease with plaque progression and vulnerability. Reducing adverse clinical events remains the ultimate goal for diagnostic tests, and this review highlights evidence supporting the prognostic value of physiological metrics in predicting o...
Article
Incomplete stent apposition (ISA, also known as malapposition) is a complication that affects day-to-day coronary stenting procedures. ISA is more prominent in complex arterial geometries, such as curvature, as. a result of the limited conformability of coronary stents. These malapposed struts disturb the otherwise near-wall laminar blood flow and...
Article
Full-text available
Virtual fractional flow reserve (vFFR) has been evaluated as an adjunct to invasive fractional flow reserve (FFR) in the light of its operational and economic benefits. The accuracy of vFFR and the complexity of hyperemic flow simulation are still not clearly understood. This study investigates the flow–pressure relation in an idealised multiple se...
Article
Full-text available
Incomplete stent apposition (ISA) is sometimes found in stent deployment at complex lesions, and it is considered to be one of the causes of post-stenting complications, such as late stent thrombosis and restenosis. The presence of ISA leads to large recirculation bubbles behind the stent struts, which can reduce shear stress at the arterial wall t...
Article
Underexpansion and overexpansion have been incriminated as causative factors of adverse cardiac events. However, dynamic biological interaction between vessel wall and scaffold may attenuate the adverse haemodynamic impact of overexpansion or underexpansion.
Article
Full-text available
The haemodynamic behaviour of blood inside a coronary artery after stenting is greatly affected by individual stent features as well as complex geometrical properties of the artery including tortuosity and curvature. Regions at higher risk of restenosis, as measured by low wall shear stress (WSS < 0.5 Pa), have not yet been studied in detail in cur...
Article
Full-text available
Objectives: This study sought to assess the safety and effectiveness of the drug-filled stent (DFS) (Medtronic, Santa Rosa, California) in the treatment of patients with coronary artery disease. Background: Polymer-free drug-eluting stents have the potential to improve clinical outcomes and facilitate shorter durations of dual antiplatelet thera...
Conference Paper
Full-text available
Incomplete stent apposition (ISA) is often found in patients with drug eluting stent implantation, and lack of neointimal coverage is considered as one of the underlying mechanisms leading to late stent thrombosis. In-vivo studies using intravascular optical coherence tomography (OCT) showed that stents implanted at locations with complex arterial...
Conference Paper
Full-text available
Computational fluid dynamics (CFD) studies play an important role in the analysis and prediction of atherosclerosis in coronary arteries. Haemodynamics, in particular endothelial shear stress (ESS), is believed to influence the unhealthy development of the endothelium. In this study, we compared the geometric variances of a patient-specific arteria...
Chapter
Cobalt-chromium (CoCr) stents were largely born out of the need for a new generation of coronary stents preserving or improving the safety, efficacy, and deliverability of earlier iterations. This chapter provides an overview of several material and chemical properties of CoCr alloys that contribute to these stents’ superior biomechanics and biocom...
Chapter
The last decade has seen a paradigm shift in access site practice with an extraordinary uptake of radial artery access for both coronary angiography and interventional cardiac procedures. The benefits of the radial artery as an access site for catheterization is primarily because of its superficial compressible location allowing early effective hem...
Chapter
With the goal of reducing vessel injury, the conventional approach to stent design has prioritized flexibility and conformability to the vessel wall. This strategy has contributed to several immensely successful devices, among them the platinum-chromium everolimus-eluting stents. This chapter begins with a brief discussion of the platinum-chromium...
Chapter
This chapter reviews the pathogenesis of atherosclerosis and the inflammatory cascades leading to plaque progression and destabilization. New coronary imaging modalities and developments in computer modeling are critiqued as tools to help improve the understanding of cardiovascular diseases. The risk of major thrombotic and thromboembolic complicat...
Article
Full-text available
Calculation of fractional flow reserve (FFR) based on computational fluid dynamics (CFD) requires reconstruction of patient-specific coronary geometry and estimation of hyperemic flow rate. Coronary computed tomography angiography (CCTA) and invasive coronary angiography (ICA) are two dominating imaging modalities used for the geometrical reconstru...
Article
Minimisation of radiation exposure with cardiac imaging reduces the potential of secondary side effects. Radiation exposure from myocardial perfusion scintigraphy and computed tomography coronary angiography (CTCA) was compared. Overall doses were low with both modalities. Doses were lower in the CTCA group, but by only a small difference of 1.1mSv...