Optical coherence tomography characterization of degradation kinetics between second- and third-generation resorbable magnesium scaffold.

Aims: This preclinical study aimed to establish optical coherence tomography (OCT)-derived parameters that could be used in the clinical setting for assessing strut degradation in the third-generation drug-eluting resorbable magnesium scaffold (DREAMS-3G), and characterize the comparative degradation profile against its precursor device (Magmaris scaffold).

Methods And Results: Twelve DREAMS-3G and 10 Magmaris scaffolds were implanted in juvenile pigs, and OCT images obtained at baseline and follow-up (6 or 12 months). Strut degradation was assessed by planimetric analysis and compared with OCT-derived indices to validate their diagnostic accuracy.

Intravascular ICG-enhanced NIRF-IVUS imaging to assess progressive atherosclerotic lesions in excised human coronary arteries.

Indocyanine green (ICG)-enhanced intravascular near-infrared fluorescence (NIRF) imaging enhances the information obtained with intravascular ultrasound (IVUS) by visualizing pathobiological characteristics of atherosclerotic plaques. To advance our understanding of this hybrid method, we aimed to assess the potential of NIRF-IVUS to identify different stages of atheroma progression by characterizing ICG uptake in human pathological specimens. After excision, 15 human coronary specimens from 13 adult patients were ICG-perfused and imaged with NIRF-IVUS.

Incidence of systemic inflammatory response syndrome and patient outcome following transcatheter edge-to-edge mitral valve repair.

Objectives: Systemic inflammatory response syndrome (SIRS) is a common finding after cardiovascular interventions. Data on the incidence of SIRS and its impact on outcome in patients undergoing transcatheter edge-to-edge mitral valve repair (MV-TEER) for mitral regurgitation (MR) is lacking.

Methods: From January 2013 to December 2020, 373 patients with moderate or severe MR undergoing MV-TEER were included.

Near-infrared spectroscopy-intravascular ultrasound to improve assessment of coronary artery disease severity in patients referred for transcatheter aortic valve implantation (The IMPACTavi registry): Design and rationale.

Background: Transcatheter aortic valve implantation (TAVI) was established as a standard treatment for high-operative risk patients with severe aortic stenosis (AS). Although coronary artery disease (CAD) often coexists with AS, clinical and angiographic evaluations of stenosis severity are unreliable in this specific setting. To provide precise risk stratification of coronary lesions, combined near-infrared spectroscopy and intravascular ultrasound (NIRS-IVUS) was developed to integrate morphological and molecular information on plaque composition.

The impact of extra-valvular cardiac damage on mid-term clinical outcome following transcatheter aortic valve replacement in patients with severe aortic stenosis.

Aims: To quantify extra-valvular cardiac damage associated with severe aortic valve stenosis (AS), a novel staging model was proposed. This study aimed to validate this model in patients undergoing transcatheter aortic valve replacement (TAVR) as well as to assess its prognostic impact.

Methods And Results: Based on echocardiographic findings, the following stages were applied: isolated AS (stage 0), left ventricular (LV) damage (stage 1), left atrial or mitral valve damage (stage 2), pulmonary hypertension or tricuspid regurgitation (stage 3), or right ventricular dysfunction (stage 4).

Echocardiographic evaluation of left ventricular function using an automated analysis algorithm is feasible for beginners and experts: comparison with invasive and non-invasive methods.

Aims: Echocardiographic measurement of left ventricular function using a user-friendly automated three-dimensional algorithm is highly attractive as it promises quick and accurate diagnosis, circumventing limitations associated with visual estimation or manual biplane measurements. We sought to assess the feasibility and correlation of such automated analysis with clinically established methods.

Methods: A total of 198 patients undergoing transthoracic echocardiography (TTE) with assessment of left ventricular parameters by automated software algorithm (Philips 3D-Heartmodel; 3D-HM) which additionally had either left ventricular angiography (LVA) or cardiac magnetic resonance (CMR) within 24 h of the TTE examination were analyzed.

Challenges of the newer generation of resorbable magnesium scaffolds: Lessons from failure mechanisms of the past generation.

Bioresorbable scaffolds (BRS) were developed to overcome the obstacles of metallic stents, mostly related to sustained presence of metallic foreign body in the coronary vessel. Following earlier success of single-arm BRS studies, randomized controlled trials of Absorb bioresorbable vascular scaffold (Abbott Vascular, Santa Clara, CA, USA) showed poor long-term clinical outcomes, particularly in terms of scaffold thrombosis. BRS made from magnesium alloy provide a promising alternative in terms of radial force, strut thickness and, potentially lower thrombogenicity.

Intravascular molecular imaging: translating pathophysiology of atherosclerosis into human disease conditions.

Progression of atherosclerotic plaque in coronary arteries is characterized by complex cellular and non-cellular molecular interactions. Within recent years, atherosclerosis has been recognized as inflammation-driven disease condition, where progressive stages are characterized by morphological changes in plaque composition but also relevant molecular processes resulting in increased plaque vulnerability. While existing intravascular imaging modalities are able to resolve key morphological features during plaque progression, they lack capability to characterize the molecular profile of advanced atherosclerotic plaque.

Timing and predictors of definite stent thrombosis in comatose survivors of out-of-hospital cardiac arrest undergoing percutaneous coronary intervention and therapeutic hypothermia (ST-OHCA study).

Background: Incidence of stent thrombosis (ST) in comatose survivors of out-of-hospital cardiac arrest (OHCA) undergoing immediate percutaneous coronary intervention (PCI) and therapeutic hypothermia (TH) varies considerably, from 2.7% to 31.2%, in retrospective studies.

Periprocedural myocardial injury according to optical characteristics of neointima and treatment modality of in-stent restenosis.

Aims: Aim of the present study was to investigate the impact of increasing neointimal inhomogeneity and neoatherosclerosis as well as of treatment modality of in-stent restenosis (ISR) on the occurrence of periprocedural myocardial injury (PMI).

Methods And Results: Patients with normal or stable/falling increased baseline high-sensitivity troponin T (hs-cTnT) undergoing intravascular optical coherence tomography (OCT) and subsequent percutaneous coronary intervention (PCI) of ISR by means of drug-coated balloon (DCB) or drug-eluting stent (DES) were included. Overall, 128 patients were subdivided into low (n = 64) and high (n = 64) inhomogeneity groups, based on the median of distribution of non-homogeneous quadrants.

Histopathology-Based Deep-Learning Predicts Atherosclerotic Lesions in Intravascular Imaging.

Optical coherence tomography is a powerful modality to assess atherosclerotic lesions, but detecting lesions in high-resolution OCT is challenging and requires expert knowledge. Deep-learning algorithms can be used to automatically identify atherosclerotic lesions, facilitating identification of patients at risk. We trained a deep-learning algorithm (DeepAD) with co-registered, annotated histopathology to predict atherosclerotic lesions in optical coherence tomography (OCT).

Validation and application of OCT tissue attenuation index for the detection of neointimal foam cells.

Neointimal infiltration with foamy macrophages is recognized as an early and important sign of de-novo atherosclerosis after stent implantation (neoatherosclerosis). Recent histopathological studies have proven that automated quantification of signal attenuation using intravascular optical coherence tomography (OCT) imaging allows for sensitive identification of macrophages in native atherosclerotic disease. Whether this is true for neointimal foam cells in the setting of neoatherosclerosis remains unknown.

Preclinical investigation of neoatherosclerosis in magnesium-based bioresorbable scaffolds versus thick-strut drug-eluting stents.

Aims: Neoatherosclerosis is a frequent finding after implantation of permanent metallic stents. Bioresorbable scaffolds (BRS) are considered to reduce the incidence of neoatherosclerosis owing to their dissolution and consequent vascular restoration. The aim of this study was to evaluate the formation of neoatherosclerosis between magnesium-based BRS and thick-strut metallic drug-eluting stents (DES) in a rabbit model of neoatherosclerosis and in proportion to the effect of high-dose statin medication.

Thrombus NET content is associated with clinical outcome in stroke and myocardial infarction.

Objective: To investigate whether immune cell composition and content of neutrophil extracellular traps (NETs) in relation to clinical outcome are different between acute ischemic stroke (AIS) and acute myocardial infarction (AMI), we performed histologic analysis and correlated results with clinical and procedural parameters.

Methods: We retrieved thrombi from patients with AIS (n = 71) and AMI (n = 72) during endovascular arterial recanalization and analyzed their immune cell composition and NET content by immunohistology. We then associated thrombus composition with procedural parameters and outcome in AIS and with cardiac function in patients with AMI.

Are we curing one evil with another? A translational approach targeting the role of neoatherosclerosis in late stent failure.

Neoatherosclerosis is defined as foamy macrophage infiltration into the peri-strut or neointimal area after stent implantation, potentially leading to late stent failure through progressive atherosclerotic changes including calcification, fibroatheroma, thin-cap fibroatheroma, and rupture with stent thrombosis (ST) in advanced stages. Human autopsy as well as intravascular imaging studies have led to the understanding of neoatherosclerosis formation as a similar but significantly accelerated pathophysiology as compared to native atherosclerosis. This acceleration is mainly based on disrupted endothelial integrity with insufficient barrier function and augmented transmigration of lipids following vascular injury after coronary intervention and especially after implantation of drug-eluting stents.

Small Dimension-Big Impact! Nanoparticle-Enhanced Non-Invasive and Intravascular Molecular Imaging of Atherosclerosis In Vivo.

Extensive translational research has provided considerable progress regarding the understanding of atherosclerosis pathophysiology over the last decades. In contrast, implementation of molecular in vivo imaging remains highly limited. In that context, nanoparticles represent a useful tool.

No effect of thymosin beta-4 on the expression of the transcription factor Islet-1 in the adult murine heart.

The transcription factor Islet-1 marks a progenitor cell population of the second heart field during cardiogenesis. In the adult heart Islet-1 expression is limited to the sinoatrial node, the ventricular outflow tract, and parasympathetic ganglia. The regenerative effect in the injured mouse ventricle of thymosin beta-4 (TB4), a 43-aminoacid peptide, was associated with increased Islet-1 immunostaining, suggesting the induction of an Islet-1-positive progenitor state by TB4.

Neoatherosclerosis: from basic principles to intravascular imaging.

Development of new atherosclerotic lesions within the neointima of stented vessels has been recognized as a novel disease manifestation of atherosclerosis (neoatherosclerosis), often manifesting as in-stent restenosis (ISR) or in-stent thrombosis (ST). The pathobiology of this entity is still not fully understood and definite diagnosis is challenging owing to limitations in resolution of contemporary intravascular imaging modalities and lack of consequent histopathology correlation studies. Yet, intravascular imaging has emerged as the gold standard for the diagnosis of in-stent pathologies, the most routinely used modalities being intravascular ultrasound (IVUS) and optical coherence tomography (OCT).

Assessment of DNA synthesis in Islet-1⁺ cells in the adult murine heart.

Rationale: Islet-1 positive (Islet-1(+)) cardiac progenitor cells give rise to the right ventricle, atria and outflow tract during murine cardiac development. In the adult heart Islet-1 expression is limited to parasympathetic neurons, few cardiomyocytes, smooth muscle cells, within the proximal aorta and pulmonary artery and sinoatrial node cells. Its role in these cells is unknown.