Evelyn Regar

• PhD
• Erasmus MC

Safety and efficacy of coronary drug-eluting stents (DES) are often preclinically tested using healthy or minimally diseased swine. These generally show significant fibrotic neointima at follow-up, while in patients, incomplete healing is often observed. The aim of this study was to investigate neointima responses to DES in swine with significant c...

Introduction: Safety and efficacy of novel drug-eluting coronary stents (DES) are often preclinically tested using healthy swine coronary models. These only show fibrotic neointima (NI) response, while in humans we also observe uncovered struts and minimal NI thickening. Therefore, healthy swine models only allow limited conclusions. Hypothesis: In...

Atherosclerotic plaques prone to rupture may cause acute myocardial infarction (MI) but can also heal without causing an event. Certain common histopathological features, including inflammation, a thin fibrous cap, positive remodelling, a large necrotic core, microcalcification, and plaque haemorrhage are commonly found in plaques causing an acute...

This consensus document, a summary of the views of an expert panel organized by the European Association of Percutaneous Cardiovascular Interventions (EAPCI), appraises the importance of ischaemia with non-obstructive coronary arteries (INOCA). Angina pectoris affects approximately 112 million people globally. Up to 70% of patients undergoing invas...

This consensus document, a summary of the views of an expert panel organized by the European Association of Percutaneous Cardiovascular Interventions (EAPCI), appraises the importance of ischaemia with non-obstructive coronary arteries (INOCA). Angina pectoris affects approximately 112 million people globally. Up to 70% of patients undergoing invas...

Objectives: The aim of this study was to evaluate the very long-term clinical outcome after radioactive stent (RS) implantation and intracoronary β radiation brachytherapy (IRBT). Background: Radioactive stents (RS) and intracoronary β radiation brachytherapy (IRBT) were introduced to prevent restenosis after percutaneous coronary intervention (...

Background: Near-infrared spectroscopy (NIRS) intravascular ultrasound imaging can detect lipid-rich plaques (LRPs). LRPs are associated with acute coronary syndromes or myocardial infarction, which can result in revascularisation or cardiac death. In this study, we aimed to establish the relationship between LRPs detected by NIRS-intravascular ul...

Objectives: The aims of this first-in-human pilot study of intravascular polarimetry were to investigate polarization properties of coronary plaques in patients and to examine the relationship of these features with established structural characteristics available to conventional optical frequency domain imaging (OFDI) and with clinical presentati...

This consensus document is the second of two reports summarizing the views of an expert panel organized by the European Association of Percutaneous Cardiovascular Interventions (EAPCI) on the clinical use of intracoronary imaging including intravascular ultrasound (IVUS), optical coherence tomography (OCT), and near infrared spectroscopy (NIRS)-IVU...

This consensus document is the second of two reports summarizing the views of an expert panel organized by the European Association of Percutaneous Cardiovascular Interventions (EAPCI) on the clinical use of intracoronary imaging including intravascular ultrasound (IVUS), optical coherence tomography (OCT), and near infrared spectroscopy (NIRS)-IVU...

Objectives The purpose of this study was to derive a biomechanical stress metric that was based on the multifactorial assessment of coronary plaque morphology, likely related to the propensity of plaque rupture in patients. Background Plaque rupture, the most frequent cause of coronary thrombosis, occurs at locations of elevated tensile stress in...

Purpose of Review The purpose of this study was to investigate the association of 26 inflammatory biomarkers (acute phase proteins, cytokines, chemokines) and renal markers with coronary lipid core burden index (LCBI) assessed by near-infrared spectroscopy (NIRS) imaging, as well as the association of these biomarkers with long-term cardiovascular...

Background: Prospective data on the associations of adiponectin with in-vivo measurements of degree, phenotype and vulnerability of coronary atherosclerosis are currently lacking. Objective: To investigate the association of plasma adiponectin with virtual histology intravascular ultrasound (VH-IVUS)-derived measures of atherosclerosis and with...

Background: Certain immunoglobulins (Ig) are proposed to have protective functions in atherosclerosis. Objectives: We tested whether serum levels of IgG and IgM autoantibodies against malondialdehyde low density lipoprotein (MDA-LDL) are associated with clinical coronary heart disease (CHD) and unfavorable plaque characteristics. Methods: NORD...

This Consensus Document is the first of two reports summarizing the views of an expert panel organized by the European Association of Percutaneous Cardiovascular Interventions (EAPCI) on the clinical use of intracoronary imaging including intravascular ultrasound (IVUS) and optical coherence tomography (OCT). The first document appraises the role o...

Objective: To examine the implications of endothelial shear stress (ESS) distribution in the formation of neoatherosclerotic lesions. Methods: Thirty six patients with neoatherosclerotic lesions on optical coherence tomography (OCT) were included in this study. The OCT data were used to reconstruct coronary anatomy. Blood flow simulation was perfor...

This Consensus Document is the first of two reports summarizing the views of an expert panel organized by the European Association of Percutaneous Cardiovascular Interventions (EAPCI) on the clinical use of intracoronary imaging including intravascular ultrasound (IVUS) and optical coherence tomography (OCT). The first document appraises the role o...

Intravascular polarimetry with polarization sensitive optical frequency domain imaging (PS-OFDI) measures polarization properties of the vessel wall and offers characterization of coronary atherosclerotic lesions beyond the cross-sectional image of arterial microstructure available to conventional OFDI. A previous study of intravascular polarimetry...

Aims: To examine the relationship between the anatomical SYNTAX score (SXscore), derived from all three coronary arteries, and coronary wall pathology measured by radiofrequency-intravascular ultrasound (RF-IVUS) and near-infrared spectroscopy (NIRS) in a single non-culprit segment. Methods and results: In referred for coronary angiography (N=88...

Background: The relationship between vessel angulation and large changes in vessel geometry after stent implantation and the occurrence of stent failure still remains unclear. We sought to investigate the association of the change in the coronary bending angle after stenting and the risk for late stent failure by three-dimensional quantitative cor...

The aim of this study was to determine if there are significant differences in curvature of the treated vessel after the deployment of a polymeric BRS or MPS in long lesions. The impact of long polymeric bioresorbable scaffolds (BRS) compared with metallic platform stents (MPS) on vessel curvature is unknown. This retrospective study compares 32 pa...

Objectives: This study aimed to evaluate whether polarimetry, performed using a modified optical frequency domain imaging (OFDI) system, can improve the assessment of histological features relevant to characterizing human coronary atherosclerosis. Background: The microscopic structure and organization of the arterial wall influence the polarizat...

Aims: The aim of the study was to assess the vascular healing response after Absorb bioresorbable vascular scaffold (BVS) implantation in patients with ST segment elevation myocardial infarction (STEMI) utilizing truly serial optical coherence tomography (OCT) examination at baseline, 12- and 24-months. Methods and results: This is the single-ce...

Aims: There is limited in vivo evidence regarding the temporal evolution of non-culprit coronary plaque morphology. We evaluated changes in non-culprit plaque morphology over time by optical coherence tomography (OCT). Methods and results: 72 patients with 257 non-culprit segments with serial OCT studies were analyzed. Non-culprit 5mm-long coron...

Aims: The European Collaborative Project on Inflammation and Vascular Wall Remodelling in Atherosclerosis - Intravascular Ultrasound (ATHEROREMO-IVUS) study has been designed as an exploratory clinical study to investigate the associations between genetic variation, coronary atherosclerosis phenotypes, and plaque vulnerability as determined by IVU...

Background DM remains a risk factor for poor outcome after stent-implantation, but little is known if and how DM affects the vascular response to BVS. Aim The aim of our study was to examine coronary responses to bioresorbable vascular scaffolds (BVS) in swine with and without diabetes mellitus fed a ‘fast-food’ diet (FF-DM and FF-NDM, respectivel...

Qualitative OCT analysis of the scaffold coverage. In the top OCT cross-sections of a homogeneous, heterogeneous, lipid-laden, calcified and mixed appearance of the coverage are depicted and on the bottom the magnifications. The ‘open’ stars indicate the black boxes of the scaffold struts at follow-up. The asterix (*) indicates the guide wire artif...

Restenosis at 3M. Restenosis of a BVS implanted in an FF-NDM swine at 3M. Coronary angiography post-implantation (A) and at 3M (B) demonstrates a significant lumen loss, with a percentage diameter stenosis (%DS) of 70% which persisted at 6M, (C). At 3M OCT was not performed as the lesion was considered too tight to allow passage of an OCT catheter...

Schematic representation of histological regions of interest. Within the neointima, 2 specific regions were discerned: para-strut neointima, defined as in contact with the struts, and subluminal: located near the lumen. (TIF)

Organized and non-organized luminal layers in the neointima. The vessels with well-organized neointimal layers (two arrows in A-D) showed dense elastic fibers (B) with 3 or more layers of αSMA positive cells (C) without lipid accumulation (D). The unorganized neointima showed myxoid degeneration (double arrow in E-H) with disarray and low density o...

Quantitative QCA and OCT analysis results. Normally distributed data are presented as mean ± SD, non-normally distributed data as median (interquartile range). FF-DM = fast-food fed diabetic swine, FF-NDM = fast-food fed non-diabetic swine, QCA = Quantitative coronary angiography, OCT = optical coherence tomography, BVS = bioresorbable vascular sca...

6M OCT pullback of BVS in an FF-NDM swine. OCT imaging at 6M in an FF-NDM swine demonstrates a highly heterogeneous appearance of the coverage. The red line in the longitudinal view of the OCT pullback (middle panel) corresponds to the location of the OCT catheter in the 2D pullback (left panel) and 3D pullback (right panel). The green line delinea...

NIRS analysis results. NIRS = Near-infrared spectroscopy, LCBI = lipid core burden index. §P-value for the difference between pre-procedure and 3M. Remaining footnotes and abbreviations are as listed in Table 1. (DOCX)

OCT strut appearance. Percentages are calculated as mean from the total (100%). Footnotes and abbreviations are as listed in Table 1. (DOCX)

6M OCT pullback of a BVS implanted in a FF-DM swine. OCT imaging at 6M in a FF-DM swine demonstrates a highly heterogeneous appearance of the coverage. The red line in the longitudinal view of the OCT pullback (middle panel) corresponds to the location of the OCT catheter in the 2D pullback (left panel) and 3D pullback (right panel). The asterisk (...

Supporting material and methods. Supporting information accompanying the manuscript titled: “Neoatherosclerosis development following bioresorbable vascular scaffold implantation in diabetic and non-diabetic swine coronary arteries”. (DOC)

Background: There is limited data on the impact of calcium (Ca) on acute procedural and clinical outcomes in patients with lesions treated with bioresorbable vascular scaffolds (BRS). We sought to evaluate the effect of calcium on procedural and clinical outcomes in a 'real world' population. Methods: Clinical outcomes were compared between pati...

Purpose Quantitative and automatic analysis of intracoronary optical coherence tomography images is useful and time-saving to assess cardiovascular risk in the clinical arena. Methods First, the interfaces of the intima, media and adventitia layers are segmented, by means of an original front propagation scheme, running in a 4D multi-parametric sp...

This short review surveys recent developments in coronary intravascular imaging technologies. We present an outline of the applications of intravascular imaging for guidance of percutaneous coronary interventions and imaging of atherosclerosis, along with emerging clinical evidence for use. Imaging of tissue composition is important for understandi...

Aims: To assess neoatherosclerotic plaque morphology in bare metal (BMS) and 1st and 2nd generation drug eluting stents (DES) in patients presenting with an event attributed to stent failure. Methods and results: Thirty five patients (11 implanted with BMS, 13 with a 1st generation and 11 with a 2nd generation DES) admitted with an event due to...

Background Malondialdehyde (MDA)-LDL is one of the main oxidation products involved in atherosclerosis pathogenesis. IgM antibodies against MDA-LDL have been generally regarded as protecting from atherosclerosis. In contrast, the role of IgG antibodies is less clear. How antibody levels relate to coronary atherosclerosis plaque characteristics stil...

Percutaneous coronary intervention is a minimally invasive procedure that is usually performed under image guidance using X-ray angiograms in which coronary arteries are opacified with contrast agent. In X-ray images, 3D objects are projected on a 2D plane, generating semi-transparent layers that overlap each other. The overlapping of structures ma...

Background: A new-generation everolimus eluting platinum-chromium stent (EePCS), offering improved radial strength, radiopacity and conformability compared to everolimus-eluting cobalt-chromium stents (EeCCS), was evaluated with regard to safety and efficacy in an all-comer cohort. Methods: A total of 1000 consecutive all-comer patients (includi...

By providing valuable information about the coronary artery wall and lumen, intravascular imaging may aid in optimizing interventional procedure results and thereby could improve clinical outcomes following percutaneous coronary intervention (PCI). Intravascular optical coherence tomography (OCT) is a light-based technology with a tissue penetratio...

Objectives: To assess whether the RXi Navvus system compared to the use of standard Fractional Flow Reserve (FFR) wires reduces total contrast volume, radiation and overall study cost in a real world patient population referred for coronary angiography or percutaneous coronary intervention. Background: FFR is the mainstay of functional hemodynam...

Lipid-core atherosclerotic plaques are associated with disease progression, procedural complications, and cardiac events. Coronary plaque lipid can be quantified in optical coherence tomography (OCT) pullbacks by measurement of lipid arcs and lipid lengths; parameters frequently used in clinical research, but labor intensive and subjective to analy...

Aims: Qualitative criteria for plaque tissue characterisation by OCT are well established, but quantitative methods lack systematic validation in vivo. High optical attenuation coefficient µt has been associated with unstable plaque features, such as lipid core. The purpose of this study was to validate optical coherence tomography (OCT) attenuati...

Aims: Fully bioresorbable Absorb poly-L-lactic-acid (PLLA) scaffolds (Abbott Vascular, Santa Clara, CA, USA) are a novel approach for the treatment of coronary narrowing. Due to the translucency of the material (PLLA), the optical coherence tomography (OCT) measurement methods used in the ABSORB trials were unique but not applicable for permanent...

Aims: We aimed to study sex differences in coronary plaque burden and plaque composition in patients with coronary artery disease (CAD). Methods and results: Virtual histology intravascular ultrasound (VH-IVUS) and near-infrared spectroscopy (NIRS) imaging of a non-culprit coronary artery was performed in 178 (23.5%) women and 581 men who underw...

Aims: Mechanisms of lumen compromise after provisional side-branch (SB) stenting are poorly understood. In this study we investigated the impact of bifurcation angle, plaque composition, and procedural strategy on SB compromise. Methods and results: Computer simulations of stent implantation were performed in Medina (1,1,1) bifurcation models. P...

Objectives: The acute expansion of bioresorbable vascular scaffolds (BRS) and drug-eluting stents (DES) in lesions with different extent of calcification was compared by Optical Coherence Tomography (OCT). Background: The acute mechanical performance of polymeric BRS in calcified lesions is poorly understood. Methods: Acute device performance...

The aim of this study was to investigate the relationship between the plaque free wall (PFW) measured by optical coherence tomography (OCT) and the plaque burden (PB) measured by intravascular ultrasound (IVUS). We hypothesize that measurement of the PFW could help to estimate the PB, thereby overcoming the limited ability of OCT to visualize the e...

The identification of vulnerable atherosclerotic plaques in the coronary arteries is emerging as an important tool for guiding atherosclerosis diagnosis and interventions. Assessment of plaque vulnerability requires knowledge of both the structure and composition of the plaque. Intravascular photoacoustic (IVPA) imaging is able to show the morpholo...

Objective: The aim of this study was to provide additional insight into the role of fibrinogen in coronary artery disease by investigating the associations between plasma fibrinogen with both degree and composition of coronary atherosclerosis as determined by virtual histology-intravascular ultrasound. Patients and methods: In 581 patients under...

Patients with diabetes mellitus (DM) are at increased risk for atherosclerosis-related events compared to non-DM (NDM) patients. With an expected worldwide epidemic of DM, early detection of anatomic and functional coronary atherosclerotic changes is gaining attention. To improve our understanding of early atherosclerosis development, we studied a...

Background and aims: We investigated whether plasma cystatin C (CysC) and neutrophil gelatinase-associated lipocalin (NGAL) are associated with intravascular ultrasound (IVUS)-derived characteristics of coronary atherosclerosis and 1-year adverse coronary events in patients with normal and mildly-to-moderately impaired kidney function. Methods:...

The efficacy of an IVUS-guided stent implantation strategy to improve acute results and clinical outcome has been described previously. OCT is another technique which allows high-resolution intracoronary imaging. However, the use of invasive imaging modalities to guide PCI has, as yet, played a limited role in current clinical practice. This may be...

Since the introduction of mechanical devices for the treatment of stenotic coronary artery disease, stent thrombosis (ST) has been an issue of major clinical concern. It is an uncommon but serious complication with high mortality and morbidity that almost always presents as death or myocardial infarction (MI), usually with electrocardiographic ST-s...

Aims: Statins are highly effective in reducing major adverse clinical events, but the direct effects on coronary plaque composition remain debatable. Our aim was to mechanistically evaluate the treatment effect of high-intensity statin therapy on compositional coronary plaque changes. Methods and results: The third Integrated Biomarker and Imagi...

Background: Conflicting results exist regarding the association between a common Haptoglobin (Hp) polymorphism and risk of coronary artery disease. We investigated the association of three functionally different anti-oxidant and anti-inflammatory Hp phenotypes (Hp1-1, Hp2-1, Hp2-2) with invasively measured degree and composition of coronary athero...

Objectives: This study sought to report on clinical outcomes beyond 1 year of the BVS Expand registry. Background: Multiple studies have proven feasibility and safety of the Absorb bioresorbable vascular scaffold (BVS) (Abbott Vascular, Santa Clara, California). However, data on medium- to long-term outcomes are limited and available only for si...

Goal: This aim of this review was to analyze and review the state of the art devices for the endovascular treatment of chronic and acute total occlusions in the different vascular beds (coronary, peripheral, carotid, and intracranial arteries) based on the forces exerted on the occlusion during treatment. Methods: The literature search was execu...

This article discusses the current value of optical coherence tomography (OCT) for the assessment of stable coronary lesions. OCT generates intracoronary images with unprecedented image resolution, namely a 10‐fold higher image resolution compared to conventional intravascular ultrasound. OCT is able to visualize a variety of atherosclerotic plaque...

Background: Limited data are available on bioresorbable vascular scaffolds (BVS) performance in bifurcations lesions and on the impact of BVS wider struts on side-branch impairment. Methods: Patients with at least one coronary bifurcation lesion involving a side-branch ≥2mm in diameter and treated with at least one BVS were examined. Procedural...

AIMS Limited data are available on bioresorbable vascular scaffold (BVS) performance in bifurcations lesions. We investigated the impact of BVS wider struts on side branch impairment. METHODS AND RESULTS Patients with at least one coronary bifurcation lesion involving a side branch ≥2 mm in diameter and treated with at least one BVS were examined...

A 50-year-old man underwent primary percutaneous coronary intervention for anterior ST-segment elevation myocardial infarction 3 h after symptom onset. After thrombectomy, polarization-sensitive optical frequency domain imaging (PS-OFDI) was performed at the culprit left anterior descending artery lesion using a prototype imaging system (Wellman Ce...

Purpose. Identification of rupture-prone plaques in coronary arteries is a major clinical challenge. Fibrous cap thickness and wall shear stress are two relevant image-based risk factors, but these two parameters are generally computed and analyzed separately. Accordingly, combining these two parameters can potentially improve the identification of...

Polarization sensitive (PS) OCT measures the polarization states of the light backscattered by tissue and provides measures of tissue birefringence and depolarization in addition to the structural OCT signal. Ex vivo studies have demonstrated that birefringence is increased in tissue rich in collagen and with elevated smooth muscle cell content. Pr...

Aims To compare optical coherence tomography (OCT)-derived plaque characteristics of the culprit and non-culprit coronary arteries in patients with Non ST elevation myocardial infarction (NSTEMI) and stable angina pectoris (SA). Methods Assessment of clinical data, angiographic, and OCT imaging including the analysis of plaques was performed. Plaqu...

Intravascular optical coherence tomography (IV-OCT) has gained widespread use over the past few years, offering highly detailed images of coronary artery pathologies and interventions [(1)][1]. In contrast to the cross-sectional view, longitudinal sections and 3-dimensional (3D) renderings are

Aims: Limited data are currently available on midterm outcomes after implantation of everolimus-eluting bioresorbable vascular scaffolds (BVS) for treatment of acute ST-elevation myocardial infarction (STEMI). Methods and results: Patients presenting with STEMI and undergoing primary percutaneous coronary intervention in the initial experience w...

Objectives: To investigate one-year outcomes after implantation of a bioresorbable vascular scaffold (BVS) in patients presenting with acute coronary syndrome (ACS) compared to stable angina patients. Background: Robust data on the outcome of BVS in the setting of ACS is still scarce. Methods: Two investigator initiated, single-center, single-...

We have developed a super fast intravascular optical coherence tomography (OCT) system called Heartbeat OCT. Heartbeat OCT relies on a Fourier Domain Mode Locked (FDML) laser and a micro-motor based catheter. The system enables acquisition of a uniformly sampled data set within one cardiac cycle, triggered by the ECG, to restore 3D OCT image fideli...