Targets for deprescribing in patients with hypertension and reflex syncope

BACKGROUND

We aimed to identify the target of deprescribing, i.e. the 24-hour SBP increase needed to achieve the greatest reduction of SBP drops.

METHOD

Forty hypertensive patients (mean age 73.6 ± 9.3 years, 26 females) with reflex syncope and SBP drops on a screening ABPM were advised to withdraw or to reduce their therapy. The study objective was the reduction of SBP drops <90 mmHg and <100 mmHg on a second ABPM performed within 3 months.

RESULTS

Out of a total of 98 drugs taken during ABPM 1, 44 were withdrawn, 16 had a dose reduction and 38 remained unchanged at the time of ABPM 2. 24-hour SBP increased from 119.7 ± 10.1 mmHg to 129.4 ± 13.2 mmHg during ABPM2. Total disappearance of daytime SBP drops <100 mmHg was achieved in 20 (50 %) patients who had 24-hour SBP of 134±13 mmHg and an increase from ABPM 1 of 12 (IQR 5-20) mmHg. Compared with the 20 patients who had persistence of drops, these patients had a greater reduction of the number of hypotensive drugs (67 % versus 19 %, p = 0.002) and a greater rate of withdrawals (62 % versus 29 %, p = 0.003).

CONCLUSION

In hypertensive patients with reflex syncope, an increase of 12 mmHg and an absolute value of 24-hour SBP of 134 mmHg appear to represent the optimal goals aimed to prevent SBP drops. Drugs withdrawal, rather than simply dose reduction, is mostly required to achieve the above target.

Interventions aimed to increase average 24-h systolic blood pressure reduce blood pressure drops in patients with reflex syncope and orthostatic intolerance

AIMS

Systolic blood pressure (SBP) drops recorded by 24-h ambulatory blood pressure (BP) monitoring (ABPM) identify patients with susceptibility to reflex syncope and orthostatic intolerance. We tested the hypothesis that treatments aimed to increase BP (reassurance, education, and lifestyle measures plus pharmacological strategies) can reduce SBP drops.

METHODS AND RESULTS

This was a multicentre, observational proof-of-concept study performed in patients with reflex syncope and/or orthostatic intolerance and with SBP drops on a screening ABPM. Among 144 eligible patients, 111 underwent a second ABPM on average 2.5 months after start of treatment. Overall, mean 24-h SBP increased from 114.1 ± 12.1 to 121.4 ± 14.5 mmHg (P < 0.0001). The number of SBP drops <90 and <100 mmHg decreased by 61%, 46% during daytime, and by 48% and 37% during 24-h period, respectively (P < 0.0001 for all). The dose-response relationship between difference in 24-h average SBP increase and reduction in number of SBP drops reached a plateau around ∼15 mmHg increase of 24-h SBP. The reduction in SBP drop rate was consistent and significant in patients who underwent deprescription of hypotensive medications (n = 44) and in patients who received BP-rising drugs (n = 67).

CONCLUSION

In patients with reflex syncope and/or orthostatic intolerance, an increase in average 24-h SBP, regardless of the implemented strategy, significantly reduced the number of SBP drops and symptom burden. A 13 mmHg increase in 24-h SBP appears to represent the optimal goal for aborting the maximal number of SBP drops, representing a possible target for future interventions. ClincalTrials.gov identifier: NCT05729724.

The Role of Fecal Microbiota Transplantation in the Allogeneic Stem Cell Transplant Setting

Microbiota changes during allogeneic hematopoietic stem cell transplantation has several known causes: conditioning chemotherapy and radiation, broad-spectrum antibiotic administration, modification in nutrition status and diet, and graft-versus-host disease. This article aims to review the current knowledge about the close link between microbiota and allogeneic stem cell transplantation setting. The PubMed search engine was used to perform this review. We analyzed data on microbiota dysbiosis related to the above-mentioned affecting factors. We also looked at treatments aimed at modifying gut dysbiosis and applications of fecal microbiota transplantation in the allogeneic stem cell transplant field, with particular interest in fecal microbiota transplantation for graft-versus-host disease (GvHD), multidrug-resistant and clostridium difficile infections, and microbiota restoration after chemotherapy and antibiotic therapy.

Physiological and Pharmacological overview of the Gonadotropin Releasing Hormone

Gonadotropin-releasing Hormone (GnRH) is a decapeptide responsible for the control of the reproductive functions. It shows C- and N-terminal aminoacid modifications and two other distinct isoforms have been so far identified. The biological effects of GnRH are mediated by binding to high-affinity G-protein couple receptors (GnRHR), showing characteristic very short C tail. In mammals, including humans, GnRH-producing neurons originate in the embryonic nasal compartment and during early embryogenesis they undergo rapid migration towards the hypothalamus; the increasing knowledge of such mechanisms improved diagnostic and therapeutic approaches to infertility. The pharmacological use of GnRH, or its synthetic peptide and non-peptide agonists or antagonists, provides a valid tool for reproductive disorders and assisted reproduction technology (ART). The presence of GnRHR in several organs and tissues indicates additional functions of the peptide. The identification of a GnRH/GnRHR system in the human endometrium, ovary, and prostate has extended the functions of the peptide to the physiology and tumor transformation of such tissues. Likely, the activity of a GnRH/GnRHR system at the level of the hippocampus, as well as its decreased expression in mice brain aging, raised interest in its possible involvement in neurogenesis and neuronal functions. In conclusion, GnRH/GnRHR appears to be a fascinating biological system that exerts several possibly integrated pleiotropic actions in the complex control of reproductive functions, tumor growth, neurogenesis, and neuroprotection. This review aims to provide an overview of the physiology of GnRH and the pharmacological applications of its synthetic analogs in the management of reproductive and non-reproductive diseases.

946 TAKOTSUBO SYNDROME TRIGGERED BY REFLEX SYNCOPE: A POTENTIALLY FATAL COMPLICATION OF A BENIGN CONDITION

Introduction

Vasovagal syncope is traditionally considered a benign condition due to parasympathetic nervous system activation. Here is a case of reflex syncopal episodes that triggered recurrent Takotsubo Syndrome (TS) with life–threatening presentation.

Report of a Case

A 71-year-old female presented to the Emergency Department (ED) complaining with dyspnoea and chest pain developed half an hour after a vasovagal syncope. Her past medical history was consistent with arterial hypertension, dyslipidaemia, and well-tolerated reflex syncopal episodes since she was a child. At hospital admission, a 12-leads ECG showed T-wave inversion in anterior leads while transthoracic echocardiogram (TTE) showed hypokinesia of the mid-apical segments, reduced left ventricular ejection fraction (LVEF) [40%], and severe mitral regurgitation (MR). Blood tests revealed increased hs-troponin I values [peak value: 1500 ng/L]. A coronary angiography (CA) was thus performed in the suspect of NSTEMI, showing non obstructive coronary disease. A diagnosis of TS was eventually made with ECG normalisation and resolution of echocardiographic abnormalities at 6 month follow-up. Five years later, the patients presented to the ED because of a new syncopal episode followed by severe pulmonary oedema. Since the presence of electrocardiographic T-wave inversion, apical segments akinesia and elevated hs-troponin I were consistent with NSTEMI, a CA was performed revealing (again!) normal coronary vessels. A suspect of TS relapse was thus made. Three months after discharge, ECG and echocardiogram were normal and a syncope diagnostic work–up was suggested. A 24/h ambulatory blood pressure monitoring demonstrated normal pressure values and a tilt test confirmed the well-established history of reflex syncope showing a remarkable cardioinhibitory response. A pacemaker implant was thus indicated.

Discussion

TS is a heart syndrome characterized by transient contractile dysfunction historically related to catecholamine activation of alpha and beta receptors. While sympathetic system involvement in the development of TS is clearly established, new evidence is emerging about the vagal role in the etiopathogenesis of the disease. Although syncopal episodes could be related to TS, because of LVOT obstruction or major arrhythmias, according to our experience, TS may be triggered by vagal hypertonus [i.e., after vasovagal syncopal episodes]. In similar situation, the implantation of a pace-maker could be considered to prevent future dangerous complications related to recurrent reflex syncope even if well tolerated by the patients.

Conclusion

In our experience, recurrent episodes of TS appeared triggered by reflex syncope. A condition traditionally considered benign may instead have life-threatening consequences. Moreover, the role of parasympathetic and vagal tone in the development of TS needs further investigation that may lead to the design of new strategies of clinical diagnosis and management.

313 BRUGADA SYNDROME MIMICRY: THE IMPORTANCE OF AN EXTENDED FOLLOW-UP

Introduction

Brugada Syndrome (BrS) is a genetically inherited condition associated with the risk of fatal arrhythmias and sudden cardiac death (SCD) occurring in a structurally normal heart. This disorder was historically related to mutations in the SCN5A gene, but recent observations suggest a more complex genetic inter-play, highlighting the possible overlap with structural cardiomyopathies, including hypertrophic cardiomyopathy (HCM).

Case Presentation

In May 2005, an asymptomatic 56-year-old man with a family history of unexplained SCD was referred to our outpatient clinic. A 12-lead ECG showed a type 2 Brugada pattern whilst transthoracic echocardiogram (TTE) was normal. Ventricular fibrillation (VF) was induced during an elective electrophysiological study and a transvenous implantable cardioverter-defibrillator (ICD) was implanted for primary prevention. More than 10 years later, in March 2022, our patient was admitted to the hospital because of palpitations. The ECG revealed a typical atrial flutter with a high ventricular rate, successfully treated with catheter ablation. Post-procedural ECG showed the persistence of type 2 Brugada pattern in association with new-onset T wave inversion in inferolateral leads and signs of ventricular hypertrophy. TTE revealed asymmetric left ventricular hypertrophy, with left ventricular outflow tract (LVOT) obstruction determined by mitral systolic anterior motion and preserved LV systolic function. The patient was treated with optimal medical therapy with symptom improvement and reduction of LVOT obstruction at a 3-month follow-up TTE.

Discussion

The distinction between Brugada phenocopy and BrS electrocardiogram patterns is not obvious, and according to our experience a Brugada type 2 pattern could be an early ECG marker of a concealed HCM which became manifest over an extended follow-up. Brugada ECG phenocopies are clinical entities characterized by type 1 or type 2 Brugada patterns elicited by an underlying condition, the disappearance of the pattern with the resolution of the condition and the absence of classical symptoms. Several pathogenic variants involving other and different genes have been recently reported suggesting a possible overlap with structural cardiomyopathies. Recently, two other cases of incidental findings of a Brugada ECG pattern in the context of HCM were described. Both patients had a common pathogenetic splicing mutation in the MYBPC3 sarcomeric gene (encoding for the cardiac myosin-binding protein C) responsible for HCM with no genetic mutations associated with Brugada syndrome. This fact suggests that patients are not simultaneously affected by BrS and HCM but a clinically manifest HCM with a specific genetic background can lead to an early BrS electrical manifestation.

Conclusion

Our experience confirms that a Brugada type 2 ECG pattern could be a very early sign of a concealed HCM manifested over 10 years later. The importance of proper risk stratification and regular follow-up has thus crucial implications in patient clinical management. However, whether Brugada pattern associated with structural heart disease is linked to an increased risk of sudden cardiac death is still unknown and needs further investigations.

Anosmin-1-Like Effect of UMODL1/Olfactorin on the Chemomigration of Mouse GnRH Neurons and Zebrafish Olfactory Axons Development

The impairment of development/migration of hypothalamic gonadotropin-releasing hormone (GnRH) neurons is the main cause of Kallmann's syndrome (KS), an inherited disorder characterized by hypogonadism, anosmia, and other developmental defects. Olfactorin is an extracellular matrix protein encoded by the UMODL1 (uromodulin-like 1) gene expressed in the mouse olfactory region along the migratory route of GnRH neurons. It shares a combination of WAP and FNIII repeats, expressed in complementary domains, with anosmin-1, the product of the ANOS1 gene, identified as the causative of KS. In the present study, we have investigated the effects of olfactorin in vitro and in vivo models. The results show that olfactorin exerts an anosmin-1-like strong chemoattractant effect on mouse-immortalized GnRH neurons (GN11 cells) through the activation of the FGFR and MAPK pathways. In silico analysis of olfactorin and anosmin-1 reveals a satisfactory similarity at the N-terminal region for the overall arrangement of corresponding WAP and FNIII domains and marked similarities between WAP domains’ binding modes of interaction with the resolved FGFR1–FGF2 complex. Finally, in vivo experiments show that the down-modulation of the zebrafish z-umodl1 gene (orthologous of UMODL1) in both GnRH3:GFP and omp2k:gap-CFPrw034 transgenic zebrafish strains leads to a clear disorganization and altered fasciculation of the neurites of GnRH3:GFP neurons crossing at the anterior commissure and a significant increase in olfactory CFP + fibers with altered trajectory. Thus, our study shows olfactorin as an additional factor involved in the development of olfactory and GnRH systems and proposes UMODL1 as a gene worthy of diagnostic investigation in KS.

Sex Steroid Regulation of Oxidative Stress in Bone Cells: An In Vitro Study

Environmental stimuli, including sex hormones and oxidative stress (OS), affect bone balance, modifying the epigenetic profiles of key osteogenic genes. Nonetheless, the interplay between sex steroids, epigenome and OS has yet be fully elucidated. This paper aims to study in vitro the role of sex steroids in OS-induced alteration in bone cells’ homeostasis, and to assess the possible contribution of epigenetic modifications. Toward this purpose, osteoblast (MC3T3-E1) and osteocyte (MLOY-4) cell lines were exposed to two different sources of free oxygen radicals, i.e., tert-butyl hydroperoxide and dexamethasone, and the protective effect of pre-treatment with androgens and estrogens was evaluated. In particular, we analyzed parameters that reflect bone cell homeostasis such as cell viability, cell migration, transcriptomic profile, transcriptional activity, and epigenetic signature. Our findings indicate that estrogens and androgens counteract OS effects. Using partially overlapping strategies, they reduce OS outcomes regarding cell viability, cell migration, the transcriptomic profile of gene families involved in bone remodeling, and epigenetic profile, i.e., H3K4me3 level. Additionally, we demonstrated that the protective effect of steroids against OS on bone homeostasis is partially mediated by the Akt pathway. Overall, these results suggest that the hormonal milieu may influence the mechanisms of age-related bone disease.

Complementary effectiveness of carotid sinus massage and tilt testing for the diagnosis of reflex syncope in patients older than 40 years: a cohort study

AIMS

Indications, methodology, and diagnostic criteria for carotid sinus massage (CSM) and tilt testing (TT) have been standardized by the 2018 Guidelines on Syncope of the European Society of Cardiology. Aim of this study was to assess their effectiveness in a large cohort which reflects the performance under 'real-world' conditions.

METHODS AND RESULTS

We analysed all patients who had undergone CSM and TT in the years 2003-2019 for suspected reflex syncope. Carotid sinus massage was performed according to the 'Method of Symptoms'. Tilt testing was performed according to the 'Italian protocol' which consists of a passive phase followed by a sublingual nitroglycerine phase. For both tests, positive test was defined as reproduction of spontaneous symptoms in the presence of bradycardia and/or hypotension. Among 3293 patients (mean age 73 ± 12 years, 48% males), 2019 (61%) had at least one test positive. A bradycardic phenotype was found in 420 patients (13%); of these, 60% were identified by CSM, 37% by TT, and 3% had both test positive. A hypotensive phenotype was found in 1733 patients (53%); of these, 98% were identified by TT and 2% had both TT and CSM positive.

CONCLUSION

The overall diagnostic yield of the tests in patients >40-year-old with suspected reflex syncope was 61%. Both CSM and TT are useful for identifying those patients with a bradycardic phenotype, whereas CSM has a limited value for identifying the hypotensive phenotype. Since the overlap of responses between tests is minimal, both CSM and TT should be performed in every patient over 40 years receiving investigation for unexplained but possible reflex syncope.

Recent advances in understanding and managing Kallmann syndrome

Many of the recent advances in our understanding of human reproductive biology and its genetic basis have arisen directly via the genetic investigation of patients with Kallmann syndrome and their families. The disease is characterised by the association of an isolated defect in the secretion (or, less commonly, action) of gonadotropin-releasing hormone (GnRH) and consequent infertility, with anosmia and potentially other associated non-reproductive features. GnRH-producing neurons are located in the hypothalamic brain region after a peculiar migration during embryonic life. To date, different genes affecting GnRH neuron development/migration have so far been implicated in Kallmann syndrome, but our knowledge of the genetic basis of the syndrome remains incomplete. From a clinical point of view, the disease has suffered from a lack of definitive diagnosis and treatment, and although progress has been made in terms of timely diagnosis and evidence-based treatment of patients, implementation remains inconsistent. These aspects will be discussed in this review, which examines new strategies for arriving at more evidence-based and patient-centred medical practice in Kallmann syndrome.

Left bundle branch area pacing in a young athlete with progressive cardiac conduction (Lev-Lenegre) disease

We present the case of a professional soccer player affected by right bundle branch block and symptomatic 2:1 atrio-ventricular block during effort, due to progressive cardiac conduction disease (Lev-Lenegre disease), who received successful left bundle branch area pacing after a failed attempt at His bundle pacing. The electrocardiographic outcome of paced QRS was consistent with a rapid electrical activation of the left ventricle through the Purkinje system. The pursue of physiological pacing was preferred over conventional, given the young age of our patient and the expectedly high burden of stimulation, to reduce the long-term risk of pacing-induced cardiomyopathy.

Antiproliferative effect of mifepristone (RU486) on human neuroblastoma cells (SK-N-SH): in vitro and in vivo studies

RU486 (mifepristone), a glucocorticoid and progesterone receptor antagonist, has been reported to exert antiproliferative effects on tumor cells. Experiments were performed to analyze the effects of RU486 on the proliferation of the human neuroblastoma, both in vitro and in vivo, using the human neuroblastoma SK-N-SH cell line. The exposure in vitro of SK-N-SH cells to RU486 revealed a dose-dependent inhibition of ³H-thymidine incorporation due to a rapid but persistent inhibition of MAPKinase activity and ERK phosphorylation. A significant decrease of SK-N-SH cell number was evident after 3, 6, and 9 days of treatment (up to 40% inhibition), without evident cell death. The inhibitory effect exerted by RU486 was not reversed by the treatment of the cells with dexamethasone or progesterone. Moreover, RU486 induced a shift in SK-N-SH cell phenotypes, with an almost complete disappearance of the neuronal-like and a prevalence of the epithelial-like cell subtypes. Finally, the treatment with RU486 of nude mice carrying a SK-N-SH cell xenograft induced a strong inhibition (up to 80%) of tumor growth. These results indicated a clear effect of RU486 on the growth of SK-N-SH neuroblastoma cells that does not seem to be mediated through the classical steroid receptors. RU486 acted mainly on the more aggressive component of the SK-N-SH cell line and its effect in vivo was achieved at a concentration already used to inhibit oocyte implantation.

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Reproducibility of carotid sinus massage

AIMS

The reproducibility of carotid sinus massage (CSM) is debated. The aim of this study was to assess the reproducibility according to the methodology and diagnostic criteria defined by the guidelines on syncope of the European Society of Cardiology.

METHOD

Among 2800 patients with syncope who underwent CSM in the years 2005-2019, 109 patients (62 males; mean age 76 ± 10 years) had performed a second CSM after a median of 28 months. Carotid sinus hypersensitivity (CSH) was diagnosed when CSM elicited a pause of >3 s and/or a fall in systolic blood pressure >50 mm Hg without reproduction of spontaneous symptoms. Carotid sinus syndrome (CSS) was established when spontaneous symptoms were reproduced in the presence of bradycardia and/or hypotension.

RESULTS

The reproducibility of CSM was 78% for 18 CSS patients, 41% for 29 CSH patients, and 77% for 62 negative patients. The corresponding interrater agreement was good for CSS (kappa = 0.66), moderate for negative CSM (kappa = 0.42), and poor for CSH (kappa = 0.30). Combining CSH and negative tests, their reproducibility rose to 90% with kappa = 0.66.

CONCLUSION

CSS but not CSH has a good reproducibility. About half of patients with CSH had a negative response at the second test, thus suggesting a great overlap between them.

Anticoagulation therapy in older patients at risk for syncopal and not-syncopal fall and/or frailty. An AcEMC-GIMSI multidisciplinary consensus document

In aged patients, the most frequent indications for anticoagulation are atrial fibrillation (AF) and venous thromboembolism for stroke and systemic embolism prevention. Despite systemic anticoagulation recommended by current guidelines for patients over 65 years, in clinical practice up to 50 % of elderly patients do not receive maintenance anticoagulation therapy. This is particularly evident in frail subjects at risk of syncopal and not-syncopal fall, fearing intracranial bleeding following a fall. As the risk of bleeding associated with falls is still debated, the boards of the Academy of Emergency Medicine and Care (AcEMC) and the Italian Multidisciplinary Working Group on Syncope (GIMSI), in order to write a consensus document, submitted to a panel of experts eight statement which could represent as many controversial topics for anticoagulant prescription in patients over 75 years. The Delphi method was used to obtain consensus between 15 physicians from different medical specialties; some of them were expert in syncope management and worked in a Syncope Unit. All had experience in prescribing oral anticoagulation. A questionnaire was sent on the appropriateness of oral anticoagulation in eight clinical situations where the risk of fall is present (frailty, cognitive impairment, previous falls, absence of caregiver, chronic renal impairment, nonvalvular AF with HAS-BLED score ≥3 or CHA2DS2-VASc score ≥3). All experts completed the questionnaire within three rounds and the consensus was reached on many but not all statements, leaving room for debate on some clinical situations. The consensus document gives useful advice for elderly patients’ management, who need oral anticoagulant therapy but are at risk of syncopal or not-syncopal fall. Nonetheless, there are some unresolved issues where an individual decision should be taken by the physician in agreement with the patient.

A novel dominant-negative FGFR1 variant causes Hartsfield syndrome by deregulating RAS/ERK1/2 pathway

Hartsfield syndrome (HS) is an ultrarare developmental disorder mainly featuring holoprosencephaly and ectrodactyly. It is caused by heterozygous or biallelic variants in FGFR1. Recently, a dominant-negative effect was suggested for FGFR1 variants associated with HS. Here, exome sequencing analysis in a 12-year-old boy with HS disclosed a novel de novo heterozygous variant c.1934C>T in FGFR1 predicted to cause the p.(Ala645Val) amino-acid substitution. In order to evaluate whether the variant, changing a highly conserved residue of the kinase domain, affects FGFR1 function, biochemical studies were employed. We measured the FGFR1 receptor activity in FGF2-treated cell lines exogenously expressing wild-type or Ala645Val FGFR1 by monitoring the activation status of FGF2/FGFR1 downstream pathways. Our analysis highlighted that RAS/ERK1/2 signaling was significantly perturbed in cells expressing mutated FGFR1, in comparison with control cells. We also provided preliminary evidence showing a modulation of the autophagic process in cells expressing mutated FGFR1. This study expands the FGFR1 mutational spectrum associated with HS, provides functional evidence further supporting a dominant-negative effect of this category of FGFR1 variants and offers initial insights on dysregulation of autophagy in HS.

ANOS1: a unified nomenclature for Kallmann syndrome 1 gene (KAL1) and anosmin-1

It is accepted that confusion regarding the description of genetic variants occurs when researchers do not use standard nomenclature. The Human Genome Organization Gene Nomenclature Committee contacted a panel of consultants, all working on the KAL1 gene, to propose an update of the nomenclature of the gene, as there was a convention in the literature of using the ‘KAL1’ symbol, when referring to the gene, but using the name ‘anosmin-1’ when referring to the protein. The new name, ANOS1, reflects protein name and is more transferrable across species.

Age-Related Frequency of Viral Lesions and Their Association with Uterine Cervical Intraepithelial Neoplasia

Data collection forms of 50,165 routine smears were examined, and of these 47,577 were considered for this study. Viral cytological lesions (VL) were observed in 101 cases: of these, 19 were associated with cervical intraepithelial neoplasia. The total frequency of VL was 0.21%, with the peak in the teenager group (0.49%). The frequency of CIN among VL showed an overall frequency of 18.8 %: this was null under 21 years of age and highest (50 %) between 51 and 60 years of age. The frequency of VL in relation to clinical provenance of patients and the season of the year did not attain significance.

The alpha-7 nicotinic acetylcholine receptor is involved in a direct inhibitory effect of nicotine on GnRH release: In vitro studies

The activation of nicotinic cholinergic receptors (nAChR) inhibits the reproductive axis; however, it is not clear whether nicotine may directly modulate the release of hypothalamic gonadotropin-releasing hormone (GnRH). Experiments carried out in GT1-1 immortalized GnRH neurons reveal the presence of a single class of high affinity α4β2 and α7 nAchR subtypes. The exposure of GT1-1 cells to nicotine does not modify the basal accumulation of GnRH. However, nicotine was found to modify GnRH pulsatility in perifusion experiments and inhibits, the release of GnRH induced by prostaglandin E₁ or by K⁺-induced cell depolarization; these effects were reversed by D-tubocurarine and α-bungarotoxin. In conclusion, the results reported here indicate that: functional nAChRs are present on GT1-1 cells, the activation of the α-bungarotoxin-sensitive subclass (α7) produces an inhibitory effect on the release of GnRH and that the direct action of nicotine on GnRH neurons may be involved in reducing fertility of smokers.

Titania supported on silica as an efficient catalyst for deep oxidative desulfurization of a model fuel with exceptionally diluted H2O2

The continuous ODS of a model fuel, catalyzed by titanium nanocrystals dispersed onto silica, was performed with <1% aqueous H₂O₂.

Long-Term Results After Single and Multiple Procedures of Ablation of Ventricular Tachycardia

INTRODUCTION

The aim of this study was to assess long-term results after single and multiple procedures of catheter ablation of ventricular tachycardia (VT). While it is generally accepted that multiple procedures are sometimes necessary in order to achieve long-term clinical success, the literature on this issue displays wide variability.

METHODS

We assessed the outcome of 160 consecutive patients who underwent 214 ablation procedures in the period 2008 to May 2015: 93 had overt structural heart disease (SHD) (previous myocardial infarction in 74 cases) and 67 had no SHD.

RESULTS

After the first procedure, the 1-year actuarial recurrence rates were 25% in patients with SHD and 5% in those without. However, recurrences increased progressively after the first year, reaching 46% and 35%, respectively, at 5 years. Overall, VT recurred in 35/93 (38%) patients with SHD and 22/67 (33%) patients without. Redo (1 to 4) procedures were performed in 28 (20%) patients with SHD and 18 (27%) patients without. After the last procedure, the 1-year actuarial recurrence rates were 5% in patients with SHD and 7% in those without, and the corresponding rates at 5 years were 23% and 7%. During follow-up, 21 patients died (all in the SHD group): no death was related to VT recurrence.

CONCLUSIONS

During long-term follow-up, VT frequently recurs after the first procedure, both in patients with SHD and in those without; multiple procedures are needed in order to increase the success rate.