Catheter ablation of right ventricular outflow tract tachycardia using contact force guidance

Outflow tract tachycardias (OTT) originating from the right or left ventricular outflow tract are thought to be benign. However, symptoms can be disabling and deterioration of left ventricular function may occur with a high arrhythmia burden. Catheter ablation has a high acute success rate of up to 90 %, but recurrences are not uncommon [1, 2]. Novel catheter designs, and mapping and ablation technologies aim to improve procedural outcome, lower the complication rate, and increase the long-term success rate [3]. The TactiCath (R) catheter (TactiCath (R), Endosense, SA Meyrin/Geneva, Switzerland, distributed by Biotronik, Berlin, Germany) is a contact force (CF) sensing radiofrequency ablation catheter that provides real-time assessment of tip-to-tissue CF during ablation [4]. Until now, it has only been used in ablation of supraventricular tachycardias, mainly atrial fibrillation. In this report, we describe the case of a patient who underwent successful ablation of right ventricular OTT and ventricular premature beats (VPBs) using CF guidance. To the best of our knowledge, this is the first case ever described of OTT ablation using CF with the TactiCath (R) catheter

The magnetic navigation system allows safety and high efficacy for ablation of arrhythmias

Aims: We aimed to evaluate the safety and long-term efficacy of the magnetic navigation system (MNS) in a large number of patients. The MNS has the potential for improving safety and efficacy based on atraumatic catheter design and superior navigation capabilities. Methods and results: In this study, 610 consecutive patients underwent ablation. Patients were divided into two age- and sex-matched groups. Ablations were performed either using MNS (group MNS, 292) or conventional manual ablation [group manual navigation (MAN), 318]. The following parameters were analysed: acute success rate, fluoroscopy time, procedure time, complications [major: pericardial tamponade, permanent atrioventricular (AV) block, major bleeding, and death; minor: minor bleeding and temporary AV block]. Recurrence rate was assessed during follow-up (15 ± 9.5 months). Subgroup analysis was performed for the following groups: atrial fibrillation, isthmus dependent and atypical atrial flutter, atrial tachycardia, AV nodal re-entrant tachycardia, circus movement tachycardia, and ventricular tachycardia (VT). Magnetic navigation system was associated with less major complications (0.34 vs. 3.2%, P = 0.01). The total numbers of complications were lower in group MNS (4.5 vs. 10%, P = 0.005). Magnetic navigation system was equally effective as MAN in acute success rate for overall groups (92 vs. 94%, P = ns). Magnetic navigation system was more successful for VTs (93 vs. 72%, P < 0.05). Less fluoroscopy was used in group MNS (30 ± 20 vs. 35 ± 25 min, P < 0.01). There were no differences in procedure times and recurrence rates for the overall groups (168 ± 67 vs. 159 ± 75 min, P = ns; 14 vs. 11%, P = ns; respectively). Conclusions: Our data suggest that the use of MNS improves safety without compromising efficiency of ablations. Magnetic navigation system is more effective than manual ablation for VTs. Published on behalf of the European Society of Cardiology. All rights reserved

Clinical experience with a novel subcutaneous implantable defibrillator system in a single center

Background: Implantable cardioverter-defibrillators (ICDs) reduce mortality in both primary and secondary prevention, but are associated with substantial short- and long-term morbidity. A totally subcutaneous ICD (S-ICD) system has been developed. We report the initial clinical experience of the first 31 patients implanted at our hospital. Methods: All patients had an ICD indication according to the ACC/AHA/ESC guidelines. The first 11 patients were part of the reported CE trial. The implantation was performed without fluoroscopy. The device was implanted subcutaneously in the anterior axillary line, with a parasternal lead tunneled from the xiphoid to the manubrial-sternal junction. Ventricular fibrillation (VF) was induced to assess detection accuracy and defibrillation efficacy using 65 J shocks. Results: Post-implant, 52 sustained episodes of VF were induced. Sensitivity was 100% and induced conversion efficacy was 100% (with standard polarity in 29 patients). Mean time to therapy was 13.9 ± 2.5 s (range 11-21.6 s). Late procedure-related complications were observed in 2 of the first 11 implantations (lead migration). During follow-up, spontaneous ventricular arrhythmias occurred in four patients, with accurate detection of all episodes. Inappropriate therapy was observed in five patients. Recurrences were prevented with reprogramming. Conclusions: The S-ICD system can be implanted without the use of fluoroscopy by using anatomical landmarks only. Episodes of VF were accurately detected using subcutaneous signals, and all induced and clinical episodes were successfully converted. The S-ICD system is a viable alternative to conventional ICD systems for selected patients

All-cause hospitalisation among people living with HIV according to gender, mode of HIV acquisition, ethnicity, and geographical origin in Europe and North America: findings from the ART-CC cohort collaboration

BACKGROUND: Understanding demographic disparities in hospitalisation is crucial for the identification of vulnerable populations, interventions, and resource planning. METHODS: Data were from the Antiretroviral Therapy Cohort Collaboration (ART-CC) on people living with HIV in Europe and North America, followed up between January, 2007 and December, 2020. We investigated differences in all-cause hospitalisation according to gender and mode of HIV acquisition, ethnicity, and combined geographical origin and ethnicity, in people living with HIV on modern combination antiretroviral therapy (cART). Analyses were performed separately for European and North American cohorts. Hospitalisation rates were assessed using negative binomial multilevel regression, adjusted for age, time since cART intitiaion, and calendar year. FINDINGS: Among 23 594 people living with HIV in Europe and 9612 in North America, hospitalisation rates per 100 person-years were 16·2 (95% CI 16·0-16·4) and 13·1 (12·8-13·5). Compared with gay, bisexual, and other men who have sex with men, rates were higher for heterosexual men and women, and much higher for men and women who acquired HIV through injection drug use (adjusted incidence rate ratios ranged from 1·2 to 2·5 in Europe and from 1·2 to 3·3 in North America). In both regions, individuals with geographical origin other than the region of study generally had lower hospitalisation rates compared with those with geographical origin of the study country. In North America, Indigenous people and Black or African American individuals had higher rates than White individuals (adjusted incidence rate ratios 1·9 and 1·2), whereas Asian and Hispanic people living with HIV had somewhat lower rates. In Europe there was a lower rate in Asian individuals compared with White individuals. INTERPRETATION: Substantial disparities exist in all-cause hospitalisation between demographic groups of people living with HIV in the current cART era in high-income settings, highlighting the need for targeted support. FUNDING: Royal Free Charity and the National Institute on Alcohol Abuse and Alcoholism

Autocrine Activation of the MET Receptor Tyrosine Kinase in Acute Myeloid Leukemia

Although the treatment of acute myeloid leukemia (AML) has improved significantly, more than half of all patients develop disease that is refractory to intensive chemotherapy. Functional genomics approaches offer a means to discover specific molecules mediating aberrant growth and survival of cancer cells. Thus, using a loss-of-function RNA interference genomic screen, we identified aberrant expression of the hepatocyte growth factor (HGF) as a critical factor in AML pathogenesis. We found HGF expression leading to autocrine activation of its receptor tyrosine kinase, MET, in nearly half of the AML cell lines and clinical samples studied. Genetic depletion of HGF or MET potently inhibited the growth and survival of HGF-expressing AML cells. However, leukemic cells treated with the specific MET kinase inhibitor crizotinib developed resistance due to compensatory upregulation of HGF expression, leading to restoration of MET signaling. In cases of AML where MET is coactivated with other tyrosine kinases, such as fibroblast growth factor receptor 1 (FGFR1), concomitant inhibition of FGFR1 and MET blocked compensatory HGF upregulation, resulting in sustained logarithmic cell kill both in vitro and in xenograft models in vivo. Our results demonstrate widespread dependence of AML cells on autocrine activation of MET, as well as the importance of compensatory upregulation of HGF expression in maintaining leukemogenic signaling by this receptor. We anticipate that these findings will lead to the design of additional strategies to block adaptive cellular responses that drive compensatory ligand expression as an essential component of the targeted inhibition of oncogenic receptors in human cancers

Parental and child factors associated with inhalant and food allergy in a population-based prospective cohort study: the Generation R Study

The prevalence of allergic diseases in children is markedly increasing to epidemic proportions. The aim of this study is to describe the presence and examine associated parental and child characteristics of allergic sensitization an

Has the Rate of CD4 Cell Count Decline before Initiation of Antiretroviral Therapy Changed over the Course of the Dutch HIV Epidemic among MSM?

Introduction:Studies suggest that the HIV-1 epidemic in the Netherlands may have become more virulent, leading to faster disease progression if untreated. Analysis of CD4 cell count decline before antiretroviral therapy (ART) initiation, a surrogate marker for disease progression, may be hampered by informative censoring as ART initiation is more likely with a steeper CD4 cell count decline.Methods:Development of CD4 cell count from 9 to 48 months after seroconversion was analyzed using a mixed-effects model and 2 models that jointly modeled CD4 cell counts and time to censoring event (start ART