Impact of Overnight Storage of Human Atrial Myocytes on Intracellular Calcium Homeostasis and Electrophysiological Utility.

Human atrial myocytes afford an attractive experimental model to investigate mechanisms underlying electrophysiological alterations in cardiovascular disease. However, this model presents limitations, such as the availability of human atrial tissue and a variable yield of myocytes isolation. Therefore, we aimed to determine whether overnight storage can increase the time window where the electrophysiological properties of human atrial myocytes can be determined.

Intraoperative intra-aortic balloon pump insertion: step by step.

A 76-year-old patient with non-ST elevation myocardial infarction was admitted to our hospital. Coronary angiography revealed significant left main and two-vessel coronary artery disease. Preoperative testing indicated severe left ventricular dysfunction.

Apolipoprotein J protects cardiomyocytes from lipid-mediated inflammation and cytotoxicity induced by the epicardial adipose tissue of diabetic patients.

Diabetic patients present increased volume and functional alterations in epicardial adipose tissue (EAT). We aimed to analyze EAT from type 2 diabetic patients and the inflammatory and cytotoxic effects induced on cardiomyocytes. Furthermore, we analyzed the cardioprotective role of apolipoprotein J (apoJ).

Increased Density of Endogenous Adenosine A Receptors in Atrial Fibrillation: From Cellular and Porcine Models to Human Patients.

Adenosine, an endogenous nucleoside, plays a critical role in maintaining homeostasis during stressful situations, such as energy deprivation or cellular damage. Therefore, extracellular adenosine is generated locally in tissues under conditions such as hypoxia, ischemia, or inflammation. In fact, plasma levels of adenosine in patients with atrial fibrillation (AF) are elevated, which also correlates with an increased density of adenosine A receptors (ARs) both in the right atrium and in peripheral blood mononuclear cells (PBMCs).

Spatial Distribution of Calcium Sparks Determines Their Ability to Induce Afterdepolarizations in Human Atrial Myocytes.

Analysis of the spatio-temporal distribution of calcium sparks showed a preferential increase in sparks near the sarcolemma in atrial myocytes from patients with atrial fibrillation (AF), linked to higher ryanodine receptor (RyR2) phosphorylation at s2808 and lower calsequestrin-2 levels. Mathematical modeling, incorporating modulation of RyR2 gating, showed that only the observed combinations of RyR2 phosphorylation and calsequestrin-2 levels can account for the spatio-temporal distribution of sparks in patients with and without AF. Furthermore, we demonstrate that preferential calcium release near the sarcolemma is key to a higher incidence and amplitude of afterdepolarizations in atrial myocytes from patients with AF.

Beta-blocker treatment of patients with atrial fibrillation attenuates spontaneous calcium release-induced electrical activity.

Aims: Atrial fibrillation (AF) has been associated with excessive spontaneous calcium release, linked to cyclic AMP (cAMP)-dependent phosphorylation of calcium regulatory proteins. Because β-blockers are expected to attenuate cAMP-dependent signaling, we aimed to examine whether the treatment of patients with β-blockers affected the incidence of spontaneous calcium release events or transient inward currents (I).

Methods: The impact of treatment with commonly used β-blockers was analyzed in human atrial myocytes from 371 patients using patch-clamp technique, confocal calcium imaging or immunofluorescent labeling.

Impact of R-Carvedilol on β2-Adrenergic Receptor-Mediated Spontaneous Calcium Release in Human Atrial Myocytes.

A hallmark of atrial fibrillation is an excess of spontaneous calcium release events, which can be mimicked by β1- or β2-adrenergic stimulation. Because β1-adrenergic receptor blockers (β1-blockers) are primarily used in clinical practice, we here examined the impact of β2-adrenergic stimulation on spontaneous calcium release and assessed whether the R- and S-enantiomers of the non-selective β- blocker carvedilol could reverse these effects. For this purpose, human atrial myocytes were isolated from patients undergoing cardiovascular surgery and subjected to confocal calcium imaging or immunofluorescent labeling of the ryanodine receptor (RyR2).

Identification of atrial-enriched lncRNA Walras linked to cardiomyocyte cytoarchitecture and atrial fibrillation.

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia in humans. Genetic and genomic analyses have recently demonstrated that the homeobox transcription factor Pitx2 plays a fundamental role regulating expression of distinct growth factors, microRNAs and ion channels leading to morphological and molecular alterations that promote the onset of AF. Here we address the plausible contribution of long non-coding (lnc)RNAs within the Pitx2>Wnt>miRNA signaling pathway.

Fast and non-destructive ultrasonic test for face masks.

As a consequence of the large demand of face masks due to the COVID19 pandemic, cheap, fast and non-destructive tests that can verify in-line the variability of the filtration capacities, prove the potential disinfection and/or evaluate the performance of new filtering materials are needed. Using two different approaches based on air-coupled ultrasounds (0.15-1.

Mini-extracorporeal circulation surgery produces less inflammation than off-pump coronary surgery.

Objectives: Both off-pump coronary artery bypass grafting surgery (OPCABG) and mini-extracorporeal circulation (MECC) have been associated with lower morbidity and mortality and less inflammation than conventional cardiopulmonary bypass. However, studies comparing the 2 techniques are scarce and the results are controversial. We compared the clinical outcomes and inflammatory response of low-risk patients undergoing coronary bypass grafting with MECC versus OPCABG.

Atrial Fibrillation and Stroke Risk After Coronary Artery Bypass Grafting Surgery.

The present multicentre study was aimed at determining the effect of preoperative atrial fibrillation (preop-AF) as stroke risk factor in coronary artery bypass graft surgery (CABG) during the perioperative period. Patients undergoing isolated CABG surgery were enrolled from 21 Spanish centers. Baseline variables related with perioperative stroke risk were recorded and analysed.

A pre-operative planning for endoprosthetic human tracheal implantation: a decision support system based on robust design of experiments.

Swallowing depends on physiological variables that have a decisive influence on the swallowing capacity and on the tracheal stress distribution. Prosthetic implantation modifies these values and the overall performance of the trachea. The objective of this work was to develop a decision support system based on experimental, numerical and statistical approaches, with clinical verification, to help the thoracic surgeon in deciding the position and appropriate dimensions of a Dumon prosthesis for a specific patient in an optimal time and with sufficient robustness.

CFD analysis of the human airways under impedance-based boundary conditions: application to healthy, diseased and stented trachea.

A computational fluid dynamics model of a healthy, a stenotic and a post-operatory stented human trachea was developed to study the respiration under physiological boundary conditions. For this, outflow pressure waveforms were computed from patient-specific spirometries by means of a method that allows to compute the peripheral impedance of the truncated bronchial generation, modelling the lungs as fractal networks. Intratracheal flow pattern was analysed under different scenarios.

FSI analysis of a human trachea before and after prosthesis implantation.

In this work we analyzed the response of a stenotic trachea after a stent implantation. An endotracheal stent is the common treatment for tracheal diseases such as stenosis, chronic cough, or dispnoea episodes. Medical treatment and surgical techniques are still challenging due to the difficulties in overcoming potential complications after prosthesis implantation.

The Sorin Freedom SOLO stentless aortic valve: easier implantation technique with potentially less risk of complications.

Aortic valve replacement by bioprosthesis is increasingly being used. Among these, stentless bioprosthesis is becoming a valid choice due to its potential hemodynamic improvement. The Sorin Freedom SOLO stentless aortic valve (FS) (Sorin Biomedica Cardio, Saluggia, Italy) is widely used, with initial and midterm promising results.

FSI Analysis of a healthy and a stenotic human trachea under impedance-based boundary conditions.

In this work, a fluid-solid interaction (FSI) analysis of a healthy and a stenotic human trachea was studied to evaluate flow patterns, wall stresses, and deformations under physiological and pathological conditions. The two analyzed tracheal geometries, which include the first bifurcation after the carina, were obtained from computed tomography images of healthy and diseased patients, respectively. A finite element-based commercial software code was used to perform the simulations.

Patient-specific models of human trachea to predict mechanical consequences of endoprosthesis implantation.

Nowadays, interventions associated with the implantation of tracheal prostheses in patients with airway pathologies are very common. This surgery may promote problems such as migration of the prosthesis, development of granulation tissue at the edges of the stent with overgrowth of the tracheal lumen or accumulation of secretions inside the prosthesis. Among the movements that the trachea carries out, swallowing seems to have harmful consequences for the tracheal tissues surrounding the prosthesis.

Long term outcome of mechanical valve prosthesis in the pulmonary position.

Objectives: Assessment of the long term outcome of mechanical valve prosthesis at pulmonary position in a population of grown-up congenital heart disease patients from a tertiary referral center.

Methods: From 1977 to 2007, 22 consecutive patients underwent a total of 25 pulmonary valve replacements with mechanical prosthesis. The most frequent underlying cardiac condition was tetralogy of Fallot (n=16, 64%) and the mean age at the time of pulmonary valve replacement was 32 ± 11 years (range 14-50 years).

FSI analysis of the coughing mechanism in a human trachea.

The main physiological function of coughing is to remove from the airways the mucus and foreign particles that enter the lungs with respirable air. However, in patients with endotracheal tubes, further surgery has to be performed to improve cough effectiveness. Thus, it is necessary to analyze how this process is carried out in healthy tracheas to suggest ways to improve its efficacy in operated patients.

Experimental characterization and constitutive modeling of the mechanical behavior of the human trachea.

Background And Aims: Cartilage and smooth muscle constitute the main structural components of the human central airways, their mechanical properties affect the flow in the trachea and contribute to the biological function of the respiratory system. The aim of this work is to find out the mechanical passive response of the principal constituents of the human trachea under static tensile conditions and to propose constitutive models to describe their behavior.

Methods: Histological analyses to characterize the tissues and mechanical tests have been made on three human trachea specimens obtained from autopsies.

Right atrium traumatic rupture presenting as chronic tamponade.

Non-penetrating cardiac traumatisms can cause cardiac rupture, myocardial contusion or, rarely, commotio cordis. In cases of rupture of a cardiac cavity, acute and severe cardiac tamponade almost invariably occurs. This paper presents an exceptionally unusual case of non-penetrating cardiac trauma resulting in right atrium rupture contained by the pericardial cavity.

Orthotopic heart transplantation in patients with transposition of the great arteries.

Thanks to progress in cardiac surgery and cardiology, pediatric patients with complex congenital heart conditions who would previously have died are now reaching adulthood. Patients with transposition of the great arteries who have undergone atrial repair can present during follow-up with progression towards heart failure as a result of progressive systemic right ventricular failure. In this situation, heart transplantation is a possible therapeutic option.