Reduced atmospheric levels of PM2.5 and decreased admissions and surgery for Ischemic stroke in Italy.

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Brugada syndrome genetics is associated with phenotype severity.

AIMS: Brugada syndrome (BrS) is associated with an increased risk of sudden cardiac death due to ventricular tachycardia/fibrillation (VT/VF) in young, otherwise healthy individuals. Despite SCN5A being the most commonly known mutated gene to date, the genotype-phenotype relationship is poorly understood and remains uncertain. This study aimed to elucidate the genotype-phenotype correlation in BrS. METHODS AND RESULTS: Brugada syndrome probands deemed at high risk of future arrhythmic events underwent genetic testing and phenotype characterization by the means of epicardial arrhythmogenic substrate (AS) mapping, and were divided into two groups according to the presence or absence of SCN5A mutation. Two-hundred probands (160 males, 80%; mean age 42.6 ± 12.2 years) were included in this study. Patients harbouring SCN5A mutations exhibited a spontaneous type 1 pattern and experienced aborted cardiac arrest or spontaneous VT/VF more frequently than the other subjects. SCN5A-positive patients exhibited a larger epicardial AS area, more prolonged electrograms and more frequently observed non-invasive late potentials. The presence of an SCN5A mutation explained >26% of the variation in the epicardial AS area and was the strongest predictor of a large epicardial area. CONCLUSION: In BrS, the genetic background is the main determinant for the extent of the electrophysiological abnormalities. SCN5A mutation carriers exhibit more pronounced epicardial electrical abnormalities and a more aggressive clinical presentation. These results contribute to the understanding of the genetic determinants of the BrS phenotypic expression and provide possible explanations for the varying degrees of disease expression.

Clinical Considerations for a Family with Dilated Cardiomyopathy, Sudden Cardiac Death, and a Novel TTN Frameshift Mutation.

Dilated cardiomyopathy (DCM) is the leading indication for heart transplantation. TTN gene truncating mutations account for about 25% of familial DCM cases and for 18% of sporadic DCM cases. The clinical relevance of specific variants in TTN has been difficult to determine because of the sheer size of the protein for which TTN encodes, as well as existing extensive genetic variation. Clinicians should communicate novel clinically-relevant variants and genotype-phenotype associations, so that animal studies evaluating the molecular mechanisms are always conducted with a focus on clinical significance. In the present study, we report for the first time the novel truncating heterozygous variant NM_001256850.1:c.72777_72783del (p.Phe24259Leufs*51) in the TTN gene and its association with DCM in a family with sudden death. This variant occurs in the A-band region of the sarcomere, in a known mutational hotspot of the gene. Truncating titin variants that occur in this region are the most common cause of DCM and have been rarely reported in asymptomatic individuals, differently from other pathogenic TTN gene variants. Further studies are warranted to better understand this particular clinically-relevant variant.

Novel SCN5A p.Val1667Asp Missense Variant Segregation and Characterization in a Family with Severe Brugada Syndrome and Multiple Sudden Deaths.

Genetic testing in Brugada syndrome (BrS) is still not considered to be useful for clinical management of patients in the majority of cases, due to the current lack of understanding about the effect of specific variants. Additionally, family history of sudden death is generally not considered useful for arrhythmic risk stratification. We sought to demonstrate the usefulness of genetic testing and family history in diagnosis and risk stratification. The family history was collected for a proband who presented with a personal history of aborted cardiac arrest and in whom a novel variant in the SCN5A gene was found. Living family members underwent ajmaline testing, electrophysiological study, and genetic testing to determine genotype-phenotype segregation, if any. Patch-clamp experiments on transfected human embryonic kidney 293 cells enabled the functional characterization of the SCN5A novel variant in vitro. In this study, we provide crucial human data on the novel heterozygous variant NM_198056.2:c.5000T>A (p.Val1667Asp) in the SCN5A gene, and demonstrate its segregation with a severe form of BrS and multiple sudden deaths. Functional data revealed a loss of function of the protein affected by the variant. These results provide the first disease association with this variant and demonstrate the usefulness of genetic testing for diagnosis and risk stratification in certain patients. This study also demonstrates the usefulness of collecting the family history, which can assist in understanding the severity of the disease in certain situations and confirm the importance of the functional studies to distinguish between pathogenic mutations and harmless genetic variants.

Novel SCN5A p.V1429M Variant Segregation in a Family with Brugada Syndrome.

Brugada syndrome (BrS) is diagnosed by the presence of an elevated ST-segment and can result in sudden cardiac death. The most commonly found mutated gene is SCN5A, which some argue is the only gene that has been definitively confirmed to cause BrS, while the potential causative effect of other genes is still under debate. While the issue of BrS genetics is currently a hot topic, current knowledge is not able to result in molecular confirmation of over half of BrS cases. Therefore, it is difficult to develop research models with wide potential. Instead, the clinical genetics first need to be better understood. In this study, we provide crucial human data on the novel heterozygous variant NM_198056.2:c.4285G>A (p.Val1429Met) in the SCN5A gene, and demonstrate its segregation with BrS, suggesting a pathogenic effect. These results provide the first disease association with this variant and are crucial clinical data to communicate to basic scientists, who could perform functional studies to better understand the molecular effects of this clinically-relevant variant in BrS.

Local release of metalloproteinases and their inhibitors after a successful revascularisation procedure.

An altered balance between metalloproteinases (MMPs) and their inhibitor tissue inhibitor of metalloproteinases (TIMPs) may influence the healing process of a minor amputation following a successful vein graft. To speed up this process, negative pressure wound therapy (NPWT) and advanced moist wound dressing have been proposed. We determined the systemic and local release of MMP-1, -2, -3, -9, TIMP-1, and TIMP-2 by enzyme linked immunosorbent assay (ELISA) technique and their influences in the healing process in 26 patients who underwent minor amputation after a successful revascularisation procedure. Twelve patients (group 1) were medicated with NPWT and 14 (group 2) with advanced moist wound dressing. Plasma samples were collected on the morning of surgery and thereafter at 1, 3, and 5 months; exudates were collected 3 days after surgery when amputation was performed and thereafter at 1, 3, and 5 months. Fifteen age-matched healthy male volunteers served as controls. All wounds healed in 5 ± 0.5 months. Follow-up plasma and local release of MMP-1, -2, -3, and -9 were overall significantly lower when compared with the preoperative levels, while those of TIMP-1 and -2 were significantly higher with no differences among the groups. Despite no differences in the healing process being observed among the two types of medications, at 1 month the local release of MMP-2 and -9 was significantly lower (P = .013 and .047, respectively) and that of TIMP-1 was significantly higher (P = .042) in group 1 as compared to group 2. A correct and aggressive local approach to the wound is able to promote the healing of the lesion stimulating the extracellular matrix turnover with local MMP/TIMP adequate balance and favouring the creation of granulation tissue. However, a successful restoration of an adequate blood flow remains the key point of a durable and rapid wound healing.

Non-invasive assessment of the arrhythmogenic substrate in Brugada syndrome using signal-averaged electrocardiogram: clinical implications from a prospective clinical trial.

AIMS: Brugada syndrome (BrS) represents a major cause of sudden cardiac death in young individuals. The risk stratification to forecast future life-threatening events is still controversial. Non-invasive assessment of late potentials (LPs) has been proposed as a risk stratification tool. However, their nature in BrS is still undetermined. The purpose of this study is to assess the electrophysiological determinants of non-invasive LPs. METHODS AND RESULTS: Two hundred and fifty consecutive patients with (Group 1, n = 96) and without (Group 2, n = 154) BrS-related symptoms were prospectively enrolled in the registry. Signal-averaged electrocardiogram (SAECG) was performed in all subjects before undergoing epicardial mapping. Group 1 patients exhibited larger arrhythmogenic substrates (AS; 5.8 ± 2.8 vs. 2.6 ± 2.1 cm2, P < 0.001) with more delayed potentials (220.4 ± 46.0 vs. 186.7 ± 42.3 ms, P < 0.001). Late potentials were present in 82/96 (85.4%) Group 1 and in 31/154 (20.1%) Group 2 individuals (P < 0.001). Patients exhibiting LPs had more frequently a spontaneous Type 1 pattern (30.1% vs. 10.9%, P < 0.001), SCN5A mutation (34.5% vs. 21.2%, P = 0.02), and exhibited a larger AS with longer potentials (5.8 ± 2.7 vs. 2.2 ± 1.7 cm2; 231.2 ± 37.3 vs. 213.8 ± 39.0 ms; P < 0.001, respectively). Arrhythmogenic substrate dimension was the strongest predictor of the presence of LPs (odds ratio 1.9; P < 0.001). An AS area of at least 3.5 cm2 identified patients with LPs (area under the curve 0.88, 95% confidence interval 0.843-0.931; P < 0.001) with a sensitivity of 86%, specificity 88%, positive predictive value 85%, and negative predictive value 89%. CONCLUSION: The results of this study support the role of the epicardial AS as an electrophysiological determinant of non-invasive LPs, which may serve as a tool in the non-invasive assessment of the BrS substrate, as SAECG-LPs could be considered an expression of the abnormal epicardial electrical activity.ClinicalTrials.gov number (NCT02641431; NCT03106701).

Comparable clinical characteristics in Brugada syndrome patients harboring SCN5A or novel SCN10A variants.

AIMS: The Brugada syndrome (BrS) is an inherited disease associated with an increased risk of sudden cardiac death. Often, the genetic cause remains undetected. Perhaps due at least in part because the NaV1.8 protein is expressed more in both the central and peripheral nervous systems than in the heart, the SCN10A gene is not included in diagnostic arrhythmia/sudden death panels in the vast majority of cardiogenetics centres. METHODS AND RESULTS: Clinical characteristics were assessed in patients harboring either SCN5A or novel SCN10A variants. Genetic testing was performed using Next Generation Sequencing on genomic DNA. Clinical characteristics, including the arrhythmogenic substrate, in BrS patients harboring novel SCN10A variants and SCN5A variants are comparable. Clinical characteristics, including gender, age, personal history of cardiac arrest/syncope, spontaneous BrS electrocardiogram pattern, family history of sudden death, and arrhythmic substrate are not significantly different between probands harboring SCN10A or SCN5A variants. CONCLUSION: Future studies are warranted to further characterize the role of these specific SCN10A variants.

Genotype-Phenotype Correlation in a Family with Brugada Syndrome Harboring the Novel p.Gln371* Nonsense Variant in the SCN5A Gene.

Brugada syndrome (BrS) is marked by coved ST-segment elevation and increased risk of sudden cardiac death. The genetics of this syndrome are elusive in over half of the cases. Variants in the SCN5A gene are the single most common known genetic unifier, accounting for about a third of cases. Research models, such as animal models and cell lines, are limited. In the present study, we report the novel NM_198056.2:c.1111C>T (p.Gln371*) heterozygous variant in the SCN5A gene, as well as its segregation with BrS in a large family. The results herein suggest a pathogenic effect of this variant. Functional studies are certainly warranted to characterize the molecular effects of this variant.

Novel SCN5A p.W697X Nonsense Mutation Segregation in a Family with Brugada Syndrome.

Brugada syndrome (BrS) is marked by an elevated ST-segment elevation and increased risk of sudden cardiac death. Variants in the SCN5A gene are considered to be molecular confirmation of the syndrome in about one third of cases, while the genetics remain a mystery in about half of the cases, with the remaining cases being attributed to variants in any of a number of genes. Before research models can be developed, it is imperative to understand the genetics in patients. Even data from humans is complicated, since variants in the most common gene in BrS, SCN5A, are associated with a number of pathologies, or could even be considered benign, depending on the variant. Here, we provide crucial human data on a novel NM_198056.2:c.2091G>A (p.Trp697X) point-nonsense heterozygous variant in the SCN5A gene, as well as its segregation with BrS. The results herein suggest a pathogenic effect of this variant. These results could be used as a stepping stone for functional studies to better understand the molecular effects of this variant in BrS.

Inflammatory biomarkers, vascular procedures of lower limbs, and wound healing.

Abnormal, persistent inflammation after bypass surgery could prevent healing of an ischaemic foot lesion. In 37 patients with peripheral arterial disease (PAD) (Rutherford Grade III Category 5) who underwent infrapopliteal vein graft and midfoot amputation, plasma levels of fibrinogen, C-reactive protein (CRP), interleukin-1 (IL-1), interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α), and matrix metalloproteinase-2 and -9 (MMP-2 and MMP-9) were determined preoperatively and during the follow up. Nine patients without clinical and Doppler evidence of arterial disease, who underwent post-traumatic midfoot primary amputation, were included in the experiment group, and 15 age-matched healthy volunteers served as control. In patients who had midfoot amputation for trauma, all wounds healed. Seven (19%) wounds in patients with an occluded graft healed, and five (13%) required major amputation because of a non-healing wound. Time required for complete healing of the lesion was similar between trauma and PAD patients (8 ± 2 months vs 11 ± 6, respectively, P = NS). Univariate analysis demonstrated that, in PAD patients, the postoperative high levels of TNF-α, IL-6, and MMP-2 and -9 were predictive for wound healing failure at 3, 6, and 9 months (P < 0.05), respectively. Furthermore, the subgroup of patients who experienced occlusion of the vein graft during follow up had a significant increase of MMP-2, -9, IL-6, and TNF-α at 3, 6, and 9 months (P < 0.05), respectively. Monitoring inflammatory markers allows the determination of patients at risk of healing failure of midfoot amputation after distal revascularisation and might predict the fate of the vein graft.

Different inflammatory cytokines release after open and endovascular reconstructions influences wound healing.

Prodromal signs of a non-healing wound after revascularisation, which might be strictly linked with impending failure of vascular reconstructions, are associated with an inflammatory response mediated by several circulating adhesion molecules, extracellular endopeptidases, and cytokines. The aim of our study was to investigate the role of selected plasma biomarkers in the prediction of both wound healing and failure of infrapopliteal vein graft or percutaneous trans-luminal angioplasty (PTA) with selective stent positioning of the superficial femoral artery (SFA) in a population affected with critical limb ischaemia. A total of 68 patients who underwent either surgical or endovascular revascularisation of the inferior limb with autologous saphenous vein infrapopliteal bypass or PTA and selective stenting of the SFA were enrolled in our study. Patients were divided into two groups according to treatment: 41 patients were included in Group 1 (open surgery) and 27 in Group 2 (endovascular procedure). Plasma and blood samples were collected on the morning of surgery and every 6 months thereafter for up to 2 years of follow-up or until an occlusion occurred of either the vein bypass graft or the vessel treated endovascularly. Fifteen age-matched healthy male volunteers were considered a reference for biological parameters. Vascular cell adhesion molecule 1 [VCAM-1]/CD106, inter-cellular adhesion molecule-1 [ICAM-1]/CD54), interleukin-1 (IL-1), interleukin-6 (IL-6), tumour necrosis factor alpha (TNF-α), and metalloproteinases (MMP)-2 and -9 plasma levels were measured with enzyme-linked immunosorbent assay (ELISA) kits. The mean observed time to heal of 54 wounds was 13 ± 4 months, with no statistically significant differences among the groups. The healing failure of the remaining wounds was strictly related to an unsuccessful open (n = 12) or endovascular (n = 8) treatment. The 2-year primary patency rate was 65% (SE = .09) in Group 1 and 52% (SE = .1) in Group 2. When compared with mean concentration values of Group 1, VCAM-1 and ICAM-1 were always significantly higher during follow-up in patients of Group 2 (P < .05). Furthermore, in the same group, IL-6 and tumour necrosis factor alpha (TNF-α) were found to be significantly higher at 6- and 12-month (P < .05) when compared with surgically treated patients. Cox regression analysis showed that elevated plasma levels of VCAM-1, ICAM-1, IL-6, and TNF-α during follow up were strongly related to impaired wound healing and/or revascularisation failure (P < .05). Elevated plasma levels of inflammatory markers VCAM-1, ICAM-1, IL-6, and TNF-α may be related to the failure of wound healing and revascularisation procedures. Interestingly, we have observed that endovascular treatments cause a higher level of these inflammation biomarkers when compared with a vein graft, although wound-healing and patency and limb salvage rates are not influenced.

Cross talk between TGF beta and TNF alfa in regression of myointimal hyperplasia.

BACKGROUND: The phenomena involved in regression of arterial myointimal hyperplasia have not been analyzed in detail. MATERIALS AND METHODS: In 24 Lewis rats, a 1-cm-long venous graft, obtained from syngenic Lewis rats, was implanted in the infrarenal aorta. After 4 wk, the grafts were removed and analyzed using scanning electron microscopy and histochemistry. The grafts showed evidence of myointimal hyperplasia; 16 of these explanted grafts were reimplanted in the vein circulation of syngenic Lewis rats. These grafts were harvested 2 wk (8 animals) and 8 wk (8 animals) later, showing complete regression of myointimal hyperplasia. RESULTS: Regression of experimental myointimal hyperplasia was correlated with the simultaneous and complementary action of Transforming Growth Factor beta and Tumor Necrosis Factor alfa. Inflammatory cytokines (IL1, IL2, and IL6) inhibit Tumor Necrosis Factor alfa-induced apoptosis. CONCLUSIONS: Regression of myointimal hyperplasia is an active process, which implies the action of several inhibitory factors. The analysis of these phenomena can lead to new therapeutic approaches to prevent myointimal hyperplasia progression.