Intracardiac echocardiography guided anatomical ablation of the arcuate ridge for drug refractory inappropriate sinus tachycardia

INTRODUCTION

Inappropriate sinus tachycardia (IST) is a common condition with frequently not tolerated beta-blockers or ivabradine and a high rate of complication in ablation strategy; we describe an alternative anatomical approach of sinus node (SN) modulation.

METHODS

This retrospective study describes a case series of 6 patients from two centers diagnosed with symptomatic IST undergoing SN ablation.

RESULTS

The mean age was 40.6 ± 13.9 years; five of the six patients were female, 100% of patients reported heart palpitations, and 66% reported dizziness, the average heart rate (HR) on a 24-h Holter was 93.2 ± 7.9 bpm. HR during the first stage of a stress test using a standard Bruce protocol was 150 ± 70 bpm, The average HR on 24-h Holter postablation was 75 ± 5.6 bpm, the sinus rate HR during stage 1 of a Bruce protocol exercise stress test was 120 ± 10 bpm.

CONCLUSION

This is the first case series reporting the acute and long-term results of a novel anatomical approach for SN modulation to treat IST targeting the arcuate ridge (AR) under intracardiac echography (ICE) guidance. The novel anatomic ICE-guided catheter ablation approach aimed to identify the earliest activation at the AR with an extension of RF lesions toward its septal region seems effective and safe to modulate the SN in symptomatic patients with IST refractory to medical treatment.

Catheter ablation of intramural outflow tract premature ventricular complexes: a multicentre study

AIMS

Ablation of outflow tract ventricular arrhythmias may be limited by a deep intramural location of the arrhythmogenic source. This study evaluates the acute and long-term outcomes of patients undergoing ablation of intramural outflow tract premature ventricular complexes (PVCs).

METHODS AND RESULTS

This multicenter series included patients with structurally normal heart or nonischemic cardiomyopathy and intramural outflow tract PVCs defined by: (a) ≥ 2 of the following criteria: (1) earliest endocardial or epicardial activation < 20ms pre-QRS; (2) Similar activation in different chambers; (3) no/transient PVC suppression with ablation at earliest endocardial/epicardial site; or (b) earliest ventricular activation recorded in a septal coronary vein. Ninety-two patients were included, with a mean PVC burden of 21.5±10.9%. Twenty-six patients had had previous ablations. All PVCs had inferior axis, with LBBB pattern in 68%. In 29 patients (32%) direct mapping of the intramural septum was performed using an insulated wire or multielectrode catheter, and in 13 of these cases the earliest activation was recorded within a septal vein. Most patients required special ablation techniques (one or more), including sequential unipolar ablation in 73%, low-ionic irrigation in 26%, bipolar ablation in 15% and ethanol ablation in 1%. Acute PVC suppression was achieved in 75% of patients. Following the procedure, the PVC burden was reduced to 5.8±8.4%. The mean follow-up was 15±14 months and 16 patients underwent a repeat ablation.

CONCLUSION

Ablation of intramural PVCs is challenging; acute arrhythmia elimination is achieved in 3/4 patients, and non-conventional approaches are often necessary for success.

Vascular Age, Metabolic Panel, Cardiovascular Risk and Inflammaging in Patients With Rheumatoid Arthritis Compared With Patients With Osteoarthritis

Introduction

The risk of cardiovascular disease (CVD) in patients with rheumatoid arthritis (RA) is 1.5–2 times higher than the general population. The fundamental risk factor for CVD is age, related to alterations at the arterial level. The aim of the study was to compare vascular age (VA) in RA patients under a strict treat-to-target (T2T) strategy with Osteoarthritis (OA) patients without strict follow up and to assess the influence of inflammaging (chronic, sterile, low-grade inflammation related to aging) and metabolic markers on VA.

Materials and Methods

This was an analytical cross-sectional study. Patients with RA (under a strict a T2T strategy) and OA patients without strict clinical follow-up were included. Patients with a history of uncontrolled hypertension, CVD, and/or current smoking were excluded. Sociodemographic, physical activity, and toxic exposure data were obtained. Waist-hip ratio and body mass index (BMI) were measured. DAS-28 (RA) and inflammatory markers, lipid profile, and glycaemia were analyzed. Pulse wave velocity (PWV) was measured (oscillometric method, Arteriograph-TensioMed®). VA was calculated based on PWV. Eleven components of inflammaging [six interleukins, three metalloproteinases (MMP), and two tissue inhibitors of metalloproteinases (TIMP)] were evaluated (Luminex® system). Univariate and bivariate analyzes (Mann Whitney U and chi-square) and correlations (Spearmans Rho) were done to compare the two groups.

Results

A total of 106 patients (74% women) were included, 52/RA and 54/OA. The mean age was 57 (Interquartile range - IQR 9 years). The BMI, waist circumference, and weight were higher in patients with OA (p &lt; 0.001). RA patients had low disease activity (DAS-28-CRP). There were no differences in VA, inflammaging nor in PWV between the two groups. VA had a positive, but weak correlation, with age and LDL. In group of RA, VA was higher in those who did not receive methotrexate (p = 0.013). LDL levels correlated with MMP1, TIMP1, and TIMP2.

Conclusions

When comparing RA patients with low levels of disease activity with OA patients with poor metabolic control, there are no differences in VA. Furthermore, methotrexate also influences VA in RA patients. This shows that implemented therapies may have an impact on not only the inflammatory state of the joint but also CVD risk.

AB0020 COMPARATIVE DESCRIPTION OF CYTOKINES AND MATRIX METALLOPROTEINASES IN A GROUP OF PATIENTS WITH RHEUMATOID ARTHRITIS AND OSTEOARTHROSIS UNDER A STRICT FOLLOW-UP COMPARED WITH COVID-19 PATIENTS

Background

COVID-19, rheumatoid arthritis (RA) and osteoarthrosis (OA) are diseases characterized by the secretion of cytokines related to the stimulation of the inflammatory response.

Objectives

To identify the differences in the cytokine and matrix metalloproteinases (MMP) profile within one acute infectious disease and two chronic inflammatory rheumatic diseases.

Methods

Analytical cross-sectional study. RA patients under a strict follow-up program (T2T evaluated every two months), OA patients without strict clinical follow-up, evaluated once or twice a year, and Severe (mortality) COVID-19 patients were included. Eleven proteins (cytokines, MMPs and its tissue inhibitors) were quantified through Luminex multiplex assay in serum samples. Univariate and bivariate analyzes were performed. Approval of Ethics Committee and informed consent were obtained.

Results

A total of 108 patients with RA and OA were compared with 20 severe COVID-19 patients. There were no significant differences through the method of Kruskall–Wallis, between RA and OA patients. IL1-B and MMP-2 were significantly lower in COVID-19 patients. Levels of IL-10, IL-1RA, IL-6, MMP-1, MMP-9, and TIMP-1 were significantly higher in COVID-19 patients. There were no differences in TNF-A, TIMP-2 and INF-G. (Table 1)

Table 1.

Significant correlations between cytokines related to Covid-19, RA and OR.

Cytokine (pg/ml) Median valuesRA (%)OACOVID-19P-valueIL-1054.9254.49116.38<0.0001aIl1-RA62.1951.82110.08<0.0001aIL1-B67.0955.3046.170.045IL-656.0951.3484.98<0.0001b 0.003cTNF-A17.514.616.3NSMMP-1d57.8454.8490.81<0.0001b 0.045cMMP-2 d70.3870.5948.560.040MMP-9 d66.2558.1686.40.007 bTIMP-1 d51.5960.99111.67<0.0001aTIMP-2 d45.247.749.6NSINF-G5.755.323.07NS

a Between RA and Covid-19 and OA and Covid-19, without differences between RA and OA. b Between OA and Covid-19.

C Between RA and Covid-19. d ng/ml.

Conclusion

Compared with RA and OA patients, severe COVID-19 patients have a great impact on the cytokines and MMPs addressed in this study, proving that COVID-19 patients suffer from a cytokine storm [1] when severely infected.

References

[1]R. Mulchandani, T. Lyngdoh, and A. K. Kakkar, “Deciphering the COVID-19 cytokine storm: Systematic review and meta-analysis,” Eur. J. Clin. Invest., vol. 51, no. 1, pp. 1–21, 2021, doi: 10.1111/eci.13429.

Disclosure of Interests

None declared

How to use the 12-lead ECG to predict the site of origin of idiopathic ventricular arrhythmias

Idiopathic ventricular arrhythmias may arise from anywhere in the heart, and the majority of them can be effectively treated with catheter ablation. The 12-lead electrocardiogram (ECG) is the initial mapping tool to predict the most likely site of origin and is valuable to choose the appropriate ablation strategy. Crucial to ECG interpretation is understanding the attitudinal orientation of the heart within the chest and the relationship between the different cardiac structures. In this review, we provide a stepwise anatomical approach for the localization of idiopathic ventricular arrhythmias based on sequential analysis of the most relevant ECG features.

Matrix Metalloproteinase 1 as a Novel Biomarker for Monitoring Hepatocellular Carcinoma in Liver Transplant Patients

INTRODUCTION

Orthotopic liver transplantation (LT) is considered to be one of the few curative treatments available for early stages of hepatocellular carcinoma (HCC). Alfa-fetoprotein (AFP) is the most-used biomarker for HCC despite low sensitivity and specificity. Matrix metalloproteinase 1 (MMP-1) has been considered to be involved in the process of vascular invasion of the malignant cells. The objective of this study was to assess the use of MMP-1 for the management of HCC patients for LT.

METHODS

Levels in serum of MMP-1 (ng/mL) and AFP (ng/mL) were assessed in 20 HCC patients (Milan criteria) before and 1, 6, and 12 months after LT.

RESULTS

There was a strong significant correlation between levels of MMP-1 and levels of AFP (ρ = .954; P ≤ .05). There were statistical differences in the levels of MMP-1 and APF between the pre-transplantation and post-transplantation groups (1 and 12 months). Increments of both markers 6 months after LT compared with the levels 1 month after LT were detected in 4 of the 20 HCC patients. The detection of recurrence by means of imaging was coincident with the increment of both markers 6 months after LT in 3 of those 4 patients.

CONCLUSIONS

After 12 months of follow-up, levels of MMP-1 were comparable to AFP levels after LT. Levels of both markers increase 6 months after LT in patients showing recurrence, indicating discriminatory power to predict relapse and thus serving as valuable markers for HCC monitoring. MMP-1 could be useful in the management of HCC after LT.

Evaluation of a multilayered chitosan-hydroxy-apatite porous composite enriched with fibronectin or an in vitro-generated bone-like extracellular matrix on proliferation and diferentiation of osteoblasts

The use of extracellular matrix (ECM) molecules from tissues is an interesting way to induce specific responses of cells grown onto composite scaffolds to promote adhesion, proliferation and differentiation. There have been several studies on the effects on cell proliferation and differentiation of osteoprogenitor cells cultured onto composites, either adding some ECM molecules or grown in the presence of growth factors. Other studies involve the use of osteoblasts cultured on a three-dimensional (3D) matrix, enriched with ECM molecules produced by the same cells grown previously inside the composite. Here, the effect of enrichment of a novel multilayered chitosan-hydroxyapatite composite with ECM molecules produced by osteoblasts, or the addition of 25 or 50 µg/ml fibronectin to the composite, on proliferation and differentiation of osteoblasts cultured on these composites was studied. The results showed an increase in the number of osteoblasts from day 1 of culture, which was higher in the group grown onto composites enriched with the highest concentration of fibronectin or with ECM molecules produced naturally by osteoblasts cultured previously on them, when compared with the control group. However, this increment tended to decline in all groups after day 7 of culture, the day when they reached the highest peak of proliferation. Differentiation expressed as alkaline phosphatase activity followed the proliferation pattern of the cells cultivated on the scaffolds. The results demonstrate the potential offered by these enriched 3D multilayered composites for improving their ability as bone grafting material.

The major genetic determinants of HIV-1 control affect HLA class I peptide presentation

Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection.

Poly(ADP-ribose) polymerase-1 modulates interferon-gamma-inducible protein (IP)-10 expression in murine embryonic fibroblasts by stabilizing IP-10 mRNA

Poly(ADP-ribose) polymerase-1 (Parp-1) is a nuclear enzyme that uses NAD(+) as a substrate to catalyze the addition of ADP-ribose polymers on a variety of nuclear proteins, modifying transiently their biological functions. Parp-1 has been involved in transcription regulation of many genes involved in the inflammatory response including cytokines and chemokines. Accordingly, genetic deletion of Parp-1 (Parp-1(-/-)) or pharmacological blockade of Parp-1 activity in mice results in a defective inflammatory immune response which confers an advantage in different pathophysiological conditions associated with inflammation. In addition to the transcriptional control, increasing mRNA stability, mainly through the mitogen-activated protein kinase p38 (p38(MAPK)) might be an important mechanism for the tight regulation in the expression of several chemokines such as IP-10. Here we demonstrate that Parp-1 deficiency in embryonic fibroblasts results in diminished IFN-gamma-induced IP-10 expression despite normal STAT1 activation and IP-10 promoter activity. Therefore, we have analyzed the involvement of Parp-1 in IP-10 mRNA stability. Parp-1 deficient cells showed a decreased half-life of IFN-gamma-induced IP-10 transcripts associated with a defect in p38(MAPK) activation. Our results demonstrate that Parp-1 can regulate inflammatory gene expression by increasing mRNA stability, via modulating a proper p38(MAPK) signalling pathway.

Regulation of NFAT by poly(ADP-ribose) polymerase activity in T cells

The nuclear factor of activated T cells (NFAT) family of transcription factors is pivotal for T lymphocyte functionality. All relevant NFAT activation events upon T cells stimulation such as nuclear translocation, DNA binding, and transcriptional activity have been shown to be dictated by its phosphorylation state. Here, we provide evidence for a novel post-translational modification that regulates NFAT. Indeed, NFATc1 and NFATc2 are poly(ADP-ribosyl)ated by poly-ADP-ribose polymerase-1 (PARP-1). Moreover, we have also found a physical interaction between PARP-1 and both NFATc1 and NFATc2. Interestingly, PARP is activated during T cell stimulation in the absence of DNA damage, leading to ADP-ribose polymers formation and transfer to nuclear acceptor proteins. Our data suggest that poly(ADP-ribosyl)ation modulates the activation of NFAT in T cells, as PARP inhibition causes an increase in NFAT-dependent transactivation and a delay in NFAT nuclear export. Poly(ADP-ribosyl)ation will expedited NFAT export from the nucleus directly or by priming/facilitating NFAT phosphorylation. Altogether, these data point to PARP-1 and poly(ADP-ribosyl)ation as a novel regulatory mechanism of NFAT at nuclear level, suggesting a potential use of PARP as a new therapeutic target in the modulation of NFAT.

Transcriptional regulation by poly(ADP-ribose) polymerase-1 during T cell activation

Background

Accumulating evidence suggests an important role for the enzyme poly(ADP-ribose) polymerase-1 (PARP-1) as an integral part of the gene expression regulatory machinery during development and in response to specific cellular signals. PARP-1 might modulate gene expression through its catalytic activity leading to poly(ADP-ribosyl)ation of nuclear proteins or by its physical association with relevant proteins. Recently, we have shown that PARP-1 is activated during T cell activation. However, the proposed role of PARP-1 in reprogramming T cell gene expression upon activation remains largely unexplored.

Results

In the present study we use oligonucleotide microarray analysis to gain more insight into the role played by PARP-1 during the gene expression reprogramming that takes place in T cells upon activation with anti-CD3 stimulation alone, or in combination with anti-CD28 co-stimulation. We have identified several groups of genes with expression modulated by PARP-1. The expression of 129 early-response genes to anti-CD3 seems to be regulated by PARP-1 either in a positive (45 genes) or in a negative manner (84 genes). Likewise, in the presence of co-stimulation (anti-CD3 + anti-CD28 stimulation), the expression of 203 genes is also regulated by PARP-1 either up (173 genes) or down (30 genes). Interestingly, PARP-1 deficiency significantly alters expression of genes associated with the immune response such as chemokines and genes involved in the Th1/Th2 balance.

Conclusion

This study provides new insights into changes in gene expression mediated by PARP-1 upon T cell activation. Pathway analysis of PARP-1 as a nuclear signalling molecule in T cells would be of relevance for the future development of new therapeutic approaches targeting PARP-1 in the acquired immune response.

PARP-2 deficiency affects the survival of CD4+CD8+ double-positive thymocytes

Poly-(ADP-ribose) polymerase-2 (PARP-2) belongs to a large family of enzymes that synthesize and transfer ADP-ribose polymers to acceptor proteins, modifying their functional properties. PARP-2-deficient (Parp-2-/-) cells, similar to Parp-1-/- cells, are sensitive to both ionizing radiation and alkylating agents. Here we show that inactivation of mouse Parp-2, but not Parp-1, produced a two-fold reduction in CD4+CD8+ double-positive (DP) thymocytes associated with decreased DP cell survival. Microarray analyses revealed increased expression of the proapoptotic Bcl-2 family member Noxa in Parp-2-/- DP thymocytes compared to littermate controls. In addition, DP thymocytes from Parp-2-/- have a reduced expression of T-cell receptor (TCR)alpha and a skewed repertoire of TCRalpha toward the 5' Jalpha segments. Our results show that in the absence of PARP-2, the survival of DP thymocytes undergoing TCRalpha recombination is compromised despite normal amounts of Bcl-xL. These data suggest a novel role for PARP-2 as an important mediator of T-cell survival during thymopoiesis by preventing the activation of DNA damage-dependent apoptotic response during the multiple rounds of TCRalpha rearrangements preceding a positively selected TCR.

Inhibition of poly(ADP-ribose) polymerase attenuates the severity of acute pancreatitis and associated lung injury

The severity of acute pancreatitis results from the transmigration and activation of leukocytes within the pancreas and the local synthesis and release of proinflammatory-soluble mediators that transform a local injury into a systemic inflammatory response. Poly(ADP-ribose)polymerase-1 (PARP-1) is a nuclear DNA-binding protein that has been shown to play a relevant role in cell necrosis and organ failure in various diseases associated with inflammation. Therefore, we set out to investigate whether the genetic deletion of PARP-1 or PARP-2 (a new member of the PARP family) genes, or pharmacological inhibition of PARP activity might affect the development and severity of acute pancreatitis and pancreatitis-associated lung injury. Secretagogue-induced acute pancreatitis was achieved by 12 hourly intraperitoneal injections of cerulein in mice deficient in PARP-1 or PARP-2 genes, and wild-type (WT) littermate mice untreated or treated with PARP activity inhibitors. The severity of pancreatitis was assessed by measurements of serum amylase, lipase, interleukin-1beta and IL-6, pancreatic water content, histologic grading and pancreas myeloperoxidase (MPO) activity. Lung injury was evaluated by quantifying MPO activity and morphological changes. We found that the severity of acute pancreatitis and pancreatitis-associated lung injury was significantly attenuated in mice lacking PARP-1, but not PARP-2, compared with WT mice. Interestingly, administration of PARP inhibitors, 3-aminobenzamide or PJ34 (N-(6-oxo-5,6-dihydro-phenanthridin-2-yl)-N,N-dimethyacetamide HCl), in WT mice markedly decreased acute pancreatitis severity and pulmonary-associated injury in a larger extension than genetic deletion of PARP-1. Our results support the potential therapeutic application of PARP inhibitors in the development and severity of acute pancreatitis and associated lung injury.

Evaluation of glucose as a cryoprotectant for boar semen

Fertility parameters of boar spermatozoa were evaluated in vitro, after freeze-thawing the semen in three different extenders containing permeable and non-permeable cryoprotectants: A (111.0 mM Tris, 31.4 mM citric acid, 185.0 mM glucose, 20 per cent egg yolk, 3 per cent glycerol and 100 iu/ml penicillin G); B (200 mM Tris; 70.8 mM citric acid, 55.5 mM glucose, 20 per cent egg yolk, three per cent glycerol and 100 iu/ml penicillin G); C (200 mM Tris, 70.8 mM citric acid, 55.5 mM fructose, 20 per cent egg yolk, 3 per cent glycerol and 100 iu/ml penicillin G). The freeze-thawing techniques were the same for each extender. Eight ejaculates from four boars were obtained; the sperm-rich fraction of each ejaculate was extended in each of the three media at a final concentration of 400 x 106 sperm/ml, loaded into 0.5 ml straws and frozen at a rate of 30 degrees C/minute to -196 degrees C. The straws were thawed at 60 degrees C for eight seconds. Sperm motility, acrosomal integrity and in vitro sperm penetration through the zona pellucida of gilt oocytes matured in vitro were evaluated. The motility of unfrozen spermatozoa was 93.1 per cent compared with 60.7 per cent, 48.2 per cent and 35 per cent for sperm frozen in extenders A, B and C respectively; these values were all significantly different (P<0.05). There was no significant decline in sperm motility after incubation for 30 minutes in extender A, but there were significant decreases in sperm motility after 30 minutes of incubation in B and C. The percentage acrosomal integrities were 97.2 per cent for the control and 45.5 per cent, 30.3 per cent and 16.8 per cent for the frozen-thawed spermatozoa in extenders A, B and C respectively. The results of the in vitro penetration assay were 80.7 per cent when using control spermatozoa, and 42.2 per cent, 18.4 per cent and 3.3 per cent when using frozen-thawed spermatozoa in extenders A, B and C respectively

Tobramycin in bone cement. An in-depth analysis of wound, serum, and urine concentrations in patients undergoing total hip revision arthroplasty

In this prospective clinical study, ten patients were treated by revision of total hip arthroplasties utilizing tobramycin-impregnated bone cement. After the operation, serum, urine, and wound suction drainage concentrations of tobramycin were determined serially by radioimmunoassay. Although high local wound concentrations, 5.7 micrograms/ml, were maintained for as long as 48 hours, serum concentration never reached even normal therapeutic ranges (greater than 2.0 micrograms/ml). There were no immediate postoperative infections; all patients are pain-free and ambulate without external support two years after surgery. One patient who had had a preoperative infection was successfully treated for late manifestation of infection 24 months after revision. Based on the evidence obtained in this study, tobramycin in bone cement is currently acceptable for clinical use.

Avulsion of ischial apophysis

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