Gastrointestinal bleeding associated to aortic valve stenosis (Heyde's syndrome): a case series and literature review.

Background: The association among aortic valve stenosis, gastrointestinal bleeding, and anaemia due to arteriovenous malformations, known as Heyde's syndrome (HS), is poorly understood and controversial. Recently, acquired Type 2A von Willebrand syndrome (vWS 2A) was shown to be the most likely aetiological mechanism of anaemia. Case summary: We report two cases of HS in whom the percutaneous replacement of the aortic valve was resolutive for iron deficiency anaemia. Discussion: Iron deficiency anaemia and aortic stenosis are a common association in the elderly, so much that frequently; in such cases, the correction of the valvulopathy is often excluded as pre-operative anaemia is associated with higher morbidity and mortality. From this perspective, the correct diagnosis of HS is crucial to guide the decision to correct valvulopathy, as valvular substitution is resolutive for both anaemic disorders and aortic stenosis.

Permanent his bundle pacing: Description and comparison of four implantation techniques.

INTRODUCTION: Permanent His bundle pacing (HBP) is the most physiological pacing modality, and new implantation systems are now available. The aim of the present study was to describe and compare four different techniques to perform HBP. METHODS AND RESULTS: We included all consecutive patients who underwent a HBP attempt in our initial experience between June 2020 and May 2022. The success and characteristics of the procedure were compared among four implantation techniques: the Biotronik Selectra 3D sheath with Solia S60 lead (Selectra 3D), the Boston Scientific Site Selective Pacing Catheter with Ingevity lead (SSPC), the Abbott steerable stylet locator with Tendril lead (Locator), and the use of a standard stylet manually pre-shaped with a conventional pacing lead (Curved stylet). Ninety-eight patients (median age 79 years [interquartile range, 73-83], 83% men) were identified. The Selectra 3D technique was used in 43 procedures, SSPC in 26, Locator in 18 and Curved stylet in 11. The groups had similar clinical characteristics. Overall, procedural success was achieved in 91 patients (93%) with similar proportions among groups (p = .986). Fluoroscopy and procedural times were 6.0 (4.4-8.5) and 60 (45-75) min, respectively, without significant differences (p = .333 and p = .790). The rate of selective capture, the pacing threshold, and the paced QRS duration were also comparable. There was one pre-discharge HBP lead dislodgment (1%) that required implant revision. CONCLUSION: In our experience, four techniques for HBP achieved comparable results in terms of safety and effectiveness. The availability of different systems may lead to widespread use of physiological pacing.

Impedance-Based Monitoring of Mesenchymal Stromal Cell Three-Dimensional Proliferation Using Aerosol Jet Printed Sensors: A Tissue Engineering Application.

One of the main hurdles to improving scaffolds for regenerative medicine is the development of non-invasive methods to monitor cell proliferation within three-dimensional environments. Recently, an electrical impedance-based approach has been identified as promising for three-dimensional proliferation assays. A low-cost impedance-based solution, easily integrable with multi-well plates, is here presented. Sensors were developed using biocompatible carbon-based ink on foldable polyimide substrates by means of a novel aerosol jet printing technique. The setup was tested to monitor the proliferation of human mesenchymal stromal cells into previously validated gelatin-chitosan hybrid hydrogel scaffolds. Reliability of the methodology was assessed comparing variations of the electrical impedance parameters with the outcomes of enzymatic proliferation assay. Results obtained showed a magnitude increase and a phase angle decrease at 4 kHz (maximum of 2.5 kΩ and -9 degrees) and an exponential increase of the modeled resistance and capacitance components due to the cell proliferation (maximum of 1.5 kΩ and 200 nF). A statistically significant relationship with enzymatic assay outcomes could be detected for both phase angle and electric model parameters. Overall, these findings support the potentiality of this non-invasive approach for continuous monitoring of scaffold-based cultures, being also promising in the perspective of optimizing the scaffold-culture system.

Printed Smart Devices on Cellulose-Based Materials by means of Aerosol-Jet Printing and Photonic Curing.

Printed electronics is an expanding research field that can reach the goal of reducing the environmental impact on electronics exploiting renewable and biodegradable materials, like paper. In our work, we designed and tested a new method for fabricating hybrid smart devices on cellulose substrates by aerosol jet printing (AJP) and photonic curing, also known as flash lamp annealing (FLA), capable to cure low temperature materials without any damage. Three different cellulose-based materials (chromatographic paper, photopaper, cardboard) were tested. Multilayer capability and SMDs (surface mount devices) interconnections are possible permitting high flexibility in the fabrication process. Electrical and geometrical tests were performed to analyze the behavior of printed samples. Resulted resistivities are 26.3 × 10-8 m on chromatographic paper, 22.3 × 10-8 m on photopaper and 13.1 × 10-8 m on cardboard. Profilometer and optical microscope evaluations were performed to state deposition quality and penetration of the ink in cellulose materials (thicknesses equal to 24.9, 28.5, and 51 µm respectively for chromatographic paper, photopaper, and cardboard). Furthermore, bending (only chromatographic paper did not reach the break-up) and damp environment tests (no significant variations in resistance) where performed. A final prototype of a complete functioning multilayer smart devices on cellulose 3D-substrate is shown, characterized by multilayers, capacitive sensors, SMDs interconnections.

[Acute coronary syndrome with unusual finding of double coronary occlusion, acute and chronic, of the left anterior descending coronary artery]. / Sindrome coronarica acuta con inusuale riscontro di duplice occlusione, acuta e cronica, dell'arteria discendente anteriore.

In patients with acute coronary syndrome, total chronic occlusion of a non-culprit vessel is a frequent angiographic finding (10-30%) and it is associated with increased mortality. The effective treatment of these lesions results in better outcomes, and procedural success depends partly on the anatomical features of the lesion. As indicated by current guidelines, the treatment of non-infarct-related artery lesions is not recommended in the acute setting, even in case of hemodynamic instability. We here report the case of a 57-year-old patient suffering from an acute coronary syndrome with double occlusion, acute and chronic, of the left anterior descending artery, both treated in the acute setting with good angiographic and clinical results.

Support-Material-Free Microfluidics on an Electrochemical Sensors Platform by Aerosol Jet Printing.

Printed electronics have led to new possibilities in the detection and quantification of a wide range of molecules important for medical, biotechnological, and environmental fields. The integration with microfluidics is often adopted to avoid hand-deposition of little volumes of reagents and samples on miniaturized electrodes that strongly depend on operator's skills. Here we report design, fabrication and test of an easy-to-use electrochemical sensor platform with microfluidics entirely realized with Aerosol Jet Printing (AJP). We printed a six-electrochemical-sensors platform with AJP and we explored the possibility to aerosol jet print directly on it a microfluidic structure without any support material. Thus, the sacrificial material removal and/or the assembly with sensors steps are avoided. The repeatability observed when printing both conductive and ultraviolet (UV)-curable polymer inks can be supported from the values of relative standard deviation of maximum 5% for thickness and 9% for line width. We designed the whole microfluidic platform to make the sample deposition (20 µL) independent from the operator. To validate the platform, we quantified glucose at different concentrations using a standard enzyme-mediated procedure. Both mediator and enzyme were directly aerosol jet printed on working electrodes (WEs), thus the proposed platform is entirely fabricated by AJP and ready to use. The chronoamperometric tests show limit of detection (LOD) = 2.4 mM and sensitivity = 2.2 ± 0.08 µA/mM confirming the effectiveness of mediator and enzyme directly aerosol jet printed to provide sensing in a clinically relevant range (3-10 mM). The average relative standard inter-platform deviation is about 8%. AJP technique can be used for fabricating a ready-to-use microfluidic device that does not need further processing after fabrication, but is promptly available for electrochemical sample analysis.

Aerosol Jet Printed 3D Electrochemical Sensors for Protein Detection.

The use of electrochemical sensors for the analysis of biological samples is nowadays widespread and highly demanded from diagnostic and pharmaceutical research, but the reliability and repeatability still remain debated issues. In the expanding field of printed electronics, Aerosol Jet Printing (AJP) appears promising to bring an improvement in resolution, miniaturization, and flexibility. In this paper, the use of AJP is proposed to design and fabricate customized electrochemical sensors in term of geometry, materials and 3D liquid sample confinement, reducing variability in the functionalization process. After an analysis of geometrical, electrical and surface features, the optimal layout has been selected. An electrochemical test has been then performed quantifying Interleukin-8, selected as reference protein, by means of Anodic Stripping Voltammetry. AJP sensors have been compared with standard screen-printed electrodes in terms of current density and relative standard deviation. Results from AJP sensors with Ag-based Anodic Stripping Voltammetry confirmed nanostructures capability to reduce the limit of detection (from 2.1 to 0.3 ng/mL). Furthermore, AJP appeared to bring an improvement in term of relative standard deviation from 50 to 10%, if compared to screen-printed sensors. This is promising to improve reliability and repeatability of measurement techniques integrable in several biotechnological applications.

Tako-tsubo: a transitory impairment of microcirculation? A case report.

The tako-tsubo syndrome, or transient left ventricular apical ballooning, has been widely described in Japan as a cardiomyopathy which resembles acute myocardial infarction on presentation, but characterized by a normal coronary tree and a favorable outcome. Conversely few series have been described in Europe and etiology and mechanism are still unknown. We describe the case of a 74-year-old Italian woman with tako-tsubo cardiomyopathy, one of the first Italian cases reported to our knowledge. In the acute phase, echocardiography and ventriculography showed the typical mid-apical systolic left ventricular dysfunction, with an angiographically normal coronary tree. A few days after, technetium-99m single-photon emission computed tomography disclosed a large mid-apical perfusion defect and dobutamine stress echocardiography showed a typical "biphasic" response. Three months later, all of these tests normalized with normal left ventricular function. In conclusion, the results of functional tests, during the acute and subacute phases, suggest that, in the absence of evident coronary spasm, a transitory reduction of the coronary reserve played a role in the pathogenesis. In the absence of epicardial coronary obstruction this could be due to a transient microcircle dysfunction, and may be attributed to a spasm followed by impaired vasodilation capability.