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This article discusses the reactivation of Chagas disease in the myocardium after heart transplantation. The authors examined endomyocardial biopsies from patients with Chagas disease and evaluated the presence and intensity of myocarditis and Trypanosoma cruzi parasites. They found that reactivation of Chagas disease is usually associated with high-grade myocarditis, similar to acute cellular rejection. However, reactivation can also occur in biopsies with low-grade or no myocarditis. The detection of T. cruzi parasites in the biopsies is dependent on the sectioning levels, so additional examination may be necessary. [Extracted from the article]

The purpose of our work was to select phages displaying peptides capable of binding to vascular markers present in human atheroma, and validate their capacity to target the vascular markers in vitro and in low-density lipoprotein receptor knockout (LDLr/) mouse model of atherosclerosis. By peptide fingerprinting on human atherosclerotic tissues, we selected and isolated four different peptides sequences, which bind to atherosclerotic lesions and share significant similarity to known human proteins with prominent roles in atherosclerosis. The CTHRSSVVC-phage peptide displayed the strongest reactivity with human carotid atherosclerotic lesions (p < 0.05), when compared to tissues from normal carotid arteries. This peptide sequence shares similarity to a sequence present in the fifth scavenger receptor cysteine-rich (SRCR) domain of CD163, which appeared to bind to CD163, and subsequently, was internalized by macrophages. Moreover, the CTHRSSVVC-phage targets atherosclerotic lesions of a low-density lipoprotein receptor knockout (LDLr/) mouse model of atherosclerosis in vivo to High-Fat diet group versus Control group.Tetraazacyclododecane-1,4,7,10-tetraacetic acid-CTHRSSVVC peptide (DOTA-CTHRSSVVC) was synthesized and labeled with 111InCl3 in >95% yield as determined by high performance liquid chromatography (HPLC), to validate the binding of the peptide in atherosclerotic plaque specimens. The results supported our hypothesis that CTHRSSVVC peptide has a remarkable sequence for the development of theranostics approaches in the treatment of atherosclerosis and other diseases. [ABSTRACT FROM AUTHOR]

Aims: Left ventricular remodelling occurs during the chronic course of aortic regurgitation (AR) and aortic stenosis (AS), leading to myocardial hypertrophy and fibrosis. Several studies have shown that extracellular volume fraction (ECV) and indexed extracellular volume (iECV) are important surrogate markers of diffuse myocardial fibrosis (MF). Postoperative data on these cardiovascular magnetic resonance (CMR) extracellular expansion parameters for either AS or AR are scarce. This study aimed to demonstrate the postoperative changes that occur in diffuse MF, and the influence of preoperative MF on the reversal of LV remodelling, in patients with AR or AS., Methods and Results: Patients with severe AR or AS and indications for surgery were prospectively enrolled. Patients underwent pre- and postoperative CMR, and ECV and iECV were quantified. Data from 99 patients were analysed (32 with AR and 67 with AS). After surgery, the left ventricle mass index decreased in both groups (AR: 110 vs. 91 g/m2; AS: 86 vs. 68 g/m2, both P < 0.001). The late gadolinium enhancement fraction (AR: preoperative 1.9% vs. postoperative 1.7%, P = 0.575; AS: preoperative 2.4% vs. postoperative 2.4%, P = 0.615) and late gadolinium enhancement mass (AR: preoperative 3.8 g vs. postoperative 2.5 g, P = 0.635; AS: preoperative 3.4 g vs. postoperative 3.5 g, P = 0.575) remained stable in both groups. Preoperative iECV and ECV were greater in the AR group (iECV: 30 mL/m2 vs. 22 mL/m2, P = 0.001; ECV: 28.4% vs. 27.2%, P = 0.048). Indexed extracellular volume decreased after surgery in both groups (AR: 30-26.5 mL/m2, AS: 22-18.2 mL/m2, both P < 0.001); it was still greater in the AR group (AR: 26.5 mL/m2 vs. AS: 18.2 mL/m2, P < 0.001). Postoperative ECV remained stable in the AR group (preoperative 28.4% vs. postoperative 29.9%; P = 0.617) and increased in the AS group (preoperative 27.2% vs. postoperative 28.6%; P = 0.033)., Conclusion: Patients with both AR or AS presented reduction in iECV after surgery, unfolding the reversible nature of diffuse MF. In contrast to patients with AS, those with AR developed postoperative iECV regression with stable ECV, suggesting a balanced reduction in both intracellular and extracellular myocardial components., Competing Interests: Conflict of interest: None declared., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Patients undergoing coronary angiography after myocardial infarction (MI) often develop cardiac and renal dysfunction. We hypothesized that the apolipoprotein A-I mimetic peptide 4F (4F) would prevent those complications. Male Wistar rats were fed a high-cholesterol diet for 8 days. The rats were then anesthetized with isoflurane and randomly divided into five groups: a control group (sham-operated rats), and four groups of rats induced to MI by left coronary artery ligation, the rats in three of those groups being injected 6 h later, with the nonionic contrast agent iopamidol, 4F, and iopamidol plus 4F, respectively. At postprocedure hour 24 , we performed the following experiments/tests ( n = 8 rats/group): metabolic cage studies; creatinine clearance studies; analysis of creatinine, urea, sodium, potassium, triglycerides, total cholesterol, very low-, low- and high-density lipoproteins (VLDL, LDL, and HDL); immunohistochemistry; histomorphometry; Western blot analysis; and transmission electron microscopy. In another set of experiments ( n = 8 rats/group), also performed at postprocedure hour 24 , we measured mean arterial pressure, heart rate, heart rate variability, echocardiographic parameters, left ventricular systolic pressure, and left ventricular end-diastolic pressure. 4F protected against MI-induced increases in total cholesterol, triglycerides, and LDL; increased HDL levels; reversed autonomic and cardiac dysfunction; decreased the myocardial ischemic area; minimized renal and cardiac apoptosis; protected mitochondria; and strengthened endothelia possibly by minimizing Toll-like receptor 4 upregulation (thus restoring endothelial nitric oxide synthase protein expression) and by upregulating vascular endothelial growth factor protein expression. 4F-treated animals showed signs of cardiac neovascularization. The nitric oxide-dependent cardioprotection and renoprotection provided by 4F could have implications for post-MI treatment.

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). At 28-day follow-up, optical coherence tomography (OCT) and histology were used to evaluate neointimal hyperplasia and healing response., Results: According to OCT analysis, Focus np stents had a greater lumen area and less neointimal hyperplasia response than BMS and Biomatrix had. Histomorphometry results showed less neointimal hyperplasia in Focus np than in BMS. Histology showed a higher fibrin deposition in Biomatrix stent compared to Focus np and BMS., Conclusions: The new polymer-free DES with sirolimus eluted from stent-plus-balloon demonstrated safety and reduced neointimal proliferation compared with the BMS and Biomatrix stents at 28-day follow-up in this porcine coronary model. This new polymer-free DES is promising and warrants further clinical studies.

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., Methods: Histopathological analysis was obtained from a porcine model of 28-day coronary in-stent neointimal proliferation (n=13 bare stents). Traditional histopathology neointimal area (NIHPATH area) was calculated as the lumen area minus the IEL area, while the percent neointimal obstruction was defined as NIHPATH area divided by the IEL area. The IVUS/OCT-like neointima area (NIHIVUS/OCT area) was defined as the lumen area minus the stent area, while the percent neointimal obstruction was defined as NIHIVUS/OCT area divided by the stent area., Results: The neointimal area as well as the percent obstruction were significantly correlated between histopathology and IVUS/OCT-like definitions (R(2)=0.89 and 0.95 respectively; P<0.01 for both). The average absolute difference between the IVUS/OCT-like and the pathology-like measurements was close to zero, however with a relatively wide dispersion (difference for neointimal area: 0.41 mm(2) [95% CI 1.72 to (-)0.90 mm(2)]; difference for percent neointimal obstruction: 2.5% [95% CI 11.5% to (-)6.5%])., Conclusions: The present findings support the use of stent area in replacement to IEL area, as in IVUS & OCT imaging protocols, for the calculation of neointimal parameters in experimental model of restenosis.

We described a case of left ventricular pseudoaneurysm associated to a severe mitral regurgitation, complicating a inferolaterodorsal acute myocardial infarction. The lesion was found in a routine echocardiogram during the in-hospital follow-up. The well-succeeded surgical strategy and the good clinical evolution of the patient were distinguished.