In vitro heterogeneity of porcine adipose tissue-derived stem cells.

Tissue-specific adult stem cells (ASC) are heterogeneous and characterized by a mix of progenitor cells that produce cells at various stages of differentiation, and ultimately different terminally differentiated cells. Understanding the heterogeneity of ASCs may lead to the development of improved protocols of cell isolation and optimized cell therapy clinical protocols. Using a combination of enzymatic and explant culture protocols, we obtained pADSC population, which is composed by two distinct morphologies: fibroblast-like cells (FLCs) and endothelial-like cells (ELCs).

Effect of the Antioxidant Lipoic Acid in Aortic Phenotype in a Marfan Syndrome Mouse Model.

Marfan syndrome (MFS) cardiovascular manifestations such as aortic aneurysms and cardiomyopathy carry substantial morbidity/mortality. We investigated the effects of lipoic acid, an antioxidant, on ROS production and aortic remodeling in a MFS mgΔ mouse model. MFS and WT (wild-type) 1-month-old mice were allocated to 3 groups: untreated, treated with losartan, and treated with lipoic acid.

Allogeneic pASC transplantation in humanized pigs attenuates cardiac remodeling post-myocardial infarction.

Cell therapy repair strategies using adult mesenchymal stromal cells have shown promising evidence to prevent cardiac deterioration in rodents even in the absence of robust differentiation of the cells into cardiomyocytes. We tested whether increasing doses of porcine adipose-tissue derived mesenchymal stem cells (pASCs) increase cardiac tissue perfusion in pigs post-myocardial infarction (MI) receiving angiotensin-converting-enzyme inhibitor (ACE inhibitors) and Beta-blockers similarly to patients. Female pigs were subjected to MI induction by sponge permanent occlusion of left circumflex coronary artery (LCx) generating approximately 10% of injured LV area with minimum hemodynamic impact.

Peri/Epicellular Protein Disulfide Isomerase Sustains Vascular Lumen Caliber Through an Anticonstrictive Remodeling Effect.

Whole-vessel remodeling critically determines lumen caliber in vascular (patho)physiology, and it is reportedly redox-dependent. We hypothesized that the cell-surface pool of the endoplasmic reticulum redox chaperone protein disulfide isomerase-A1 (peri/epicellular=pecPDI), which is known to support thrombosis, also regulates disease-associated vascular architecture. In human coronary atheromas, PDI expression inversely correlated with constrictive remodeling and plaque stability.

Clinical performance of a novel ultrathin strut, low-dose, sirolimus-eluting stent with abluminal-only biodegradable polymeric coating for patients undergoing percutaneous coronary intervention in the daily practice.

Background: The present study aimed to evaluate the clinical performance, in the daily practice of a busy catheterization laboratory, of a novel drug-eluting stent (DES) built with an ultra-thin-strut metallic platform, eluting sirolimus at low doses, abluminal coated with biodegradable polymers, and mounted in a low-compliant delivery system.

Methods: Prospective, single-arm study, comprising all consecutive patients undergoing percutaneous coronary intervention (PCI) with the Inspiron™ sirolimus-eluting stent (SES) (Scitech, Aparecida de Goiania, Brazil). The primary endpoint was the occurrence of major adverse cardiac events (MACE) [cardiac death, non-PCI related myocardial infarction (MI), or target vessel revascularization (TVR)].

A bifurcation identifier for IV-OCT using orthogonal least squares and supervised machine learning.

Intravascular optical coherence tomography (IV-OCT) is an in-vivo imaging modality based on the intravascular introduction of a catheter which provides a view of the inner wall of blood vessels with a spatial resolution of 10-20 μm. Recent studies in IV-OCT have demonstrated the importance of the bifurcation regions. Therefore, the development of an automated tool to classify hundreds of coronary OCT frames as bifurcation or nonbifurcation can be an important step to improve automated methods for atherosclerotic plaques quantification, stent analysis and co-registration between different modalities.

A new polymer-free drug-eluting stent with nanocarriers eluting sirolimus from stent-plus-balloon compared with bare-metal stent and with biolimus A9 eluting stent in porcine coronary arteries.

Background: Permanent polymers in first generation drug-eluting stent (DES) have been imputed to be a possible cause of persistent inflammation, remodeling, malapposition and late stent thrombosis. We aim to describe the in vivo experimental result of a new polymer-free DES eluting sirolimus from stent-plus-balloon (Focus np stent, Envision Scientific) compared with a bare-metal stent (BMS) (Amazonia CroCo, Minvasys) and with a biolimus A9 eluting stent (Biomatrix, Biosensors).

Methods: In 10 juvenile pigs, 23 coronary stents were implanted in the coronary arteries (8 Amazonia CroCo, 8 Focus np, and 7 Biomatrix).

Intravascular ultrasound guidance to minimize the use of iodine contrast in percutaneous coronary intervention: the MOZART (Minimizing cOntrast utiliZation With IVUS Guidance in coRonary angioplasTy) randomized controlled trial.

Objectives: The aim of this study was to evaluate the impact of intravascular ultrasound (IVUS) guidance on the final volume of contrast agent used in patients undergoing percutaneous coronary intervention (PCI).

Background: To date, few approaches have been described to reduce the final dose of contrast agent in PCIs. We hypothesized that IVUS might serve as an alternative imaging tool to angiography in many steps during PCI, thereby reducing the use of iodine contrast.

Catheter-based induction of renal ischemia/reperfusion in swine: description of an experimental model.

Several techniques to induce renal ischemia have been proposed: clamp, PVA particles, and catheter-balloon. We report the development of a controlled, single-insult model of unilateral renal ischemia/reperfusion (I/R) without contralateral nephrectomy, using a suitable model, the pig. This is a balloon-catheter-based model using a percutaneous, interventional radiology procedure.

Development of a closed-artery catheter-based myocardial infarction in pigs using sponge and lidocaine hydrochloride infusion to prevent irreversible ventricular fibrillation.

The objectives of this study were to develop a robust, homogeneous, viable and inexpensive model of closed-artery catheter-based model of myocardial infarction (MI) in pigs without major cardiac dysfunction. Suitable animal models that mimic human cardiovascular conditions are of paramount importance to understand the effects of novel therapeutic strategies to improve tissue perfusion and prevent cardiac deterioration post-MI. Pigs (N = 21, BW = 17 ± 1 kg) receiving continuous iv lidocaine hydrochloride were subjected to percutaneous intracoronary implant of foam sponge into the proximal left circumflex coronary artery.

Preclinical study of a biodegradable polymer-based stent with abluminal sirolimus release.

Background: Bioabsorbable polymer stents with drug elution only on the abluminal surface may be safer than durable polymer drug-eluting stents.

Objective: To report the experimental findings with the Inspiron™ stent - a bioabsorbable polymer-coated stent with sirolimus release from the abluminal surface only, recently approved for clinical use.

Methods: 45 stents were implanted in the coronary arteries of 15 pigs.

Emerging technologies: polymer-free phospholipid encapsulated sirolimus nanocarriers for the controlled release of drug from a stent-plus-balloon or a stand-alone balloon catheter.

Drug-eluting stents have proven to be effective in reducing the risk of late restenosis. In order to achieve a controlled and prolonged release of the antiproliferative agent, current drug-eluting stents utilise various biodegradable as well as non-erodible polymeric blends to coat the stent surface and to serve as drug carriers. The utilisation of polymeric compounds in current drug-eluting stents may eventually limit their performance as well as their clinical applicability due to the potential induction of undesirable local reactions.

Assessment of stent strut endothelialization in iliac arteries of rabbits.

Background: Fast post-implantation stent endothelialization is desirable for theoretically reducing the possibility of stent thrombosis.

Objective: To evaluate the extent of sirolimus-eluting stent strut endothelialization (delivered from the luminal and abluminal aspects or abluminal aspect only) in the iliac arteries of rabbits.

Methods: The iliac arteries of 10 rabbits were implanted with four sirolimus-eluting stents in the luminal and abluminal aspects, three sirolimus-eluting stents in the abluminal aspect, six polymer-coated stents, and four uncoated stents.

Optical coherence tomography in conjunction with bronchoscopy.

Objective: To evaluate the feasibility of and the potential for using optical coherence tomography in conjunction with conventional bronchoscopy in the evaluation of the airways.

Methods: This was a pilot study based on an ex vivo experimental model involving three animals: one adult New Zealand rabbit and two Landrace pigs. An optical coherence tomography imaging catheter was inserted through the working channel of a flexible bronchoscope in order to reach the distal trachea of the animals.

A histopathological comparison of different definitions for quantifying in-stent neointimal tissue: implications for the validity of intracoronary ultrasound and optical coherence tomography measurements.

Purpose: Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) define neointima as the tissue encompassed between the stent and the lumen boundaries. This approach differs from the gold-standard histopathology, where neointima is traditionally calculated as the tissue between the internal elastic lamina (IEL) and the lumen. We aimed to investigate whether the neointimal assessment using IVUS and OCT-like definitions would correlate with the traditional histopathological quantification of neointima.

[Angiographic geometric predictors of myocardial infarction are not associated with ultrasonographic markers of plaque vulnerability].

Objective: Some angiographic geometric features of coronary lesions have recently been described as independent predictors of myocardial infarction. The purpose of this study was to correlate these geometric markers with intravascular ultrasound findings known to be associated with greater vulnerability to plaque rupture.

Methods: A total of 30 patients with stable coronary syndromes and de novo lesions (31 lesions) underwent coronary angiography and intravascular ultrasound (IVUS).

Anomalous origin of the left coronary artery from the pulmonary artery: report of an adult case.

We report the clinical findings, pathophysiology, diagnostic characteristics, and surgical repair of anomalous origin of the left coronary artery from the pulmonary artery in a 26-year-old female patient with a clinical diagnosis of coronary heart disease.