55 research outputs found
Heart rate modulation in stable coronary artery disease without clinical heart failure: What we have already learned from SIGNIFY?
An elevated heart rate is a marker of cardiovascular risk in patients with stable coronary artery disease. Ivabradine selectively inhibits the âfâ current in the sinus node and reduces heart rate without any modifications of blood pressure, myocardial contractility and arteriolar resistance. However the addition of ivabradine to standard therapy to reduce heart rate did not improve outcomes in the recent SIGNIFY trial. Moreover, a significant interaction between the effect of ivabradine among subgroups with and without angina was detected, with a worse outcome in patients in CCS class >II at baseline. The explanation for this surprising finding despite a significant reduction in angina and myocardial revascularization procedures is uncertain. A J-curve for heart rate was not demonstrated. We speculate a significant interference on adverse events (mainly atrial fibrillation and consequently acute coronary syndromes) and on the outcome of unfavorable interactions between ivabradine and diltiazem, verapamil and strong inhibitors of CYP3A4 (4.6% of the total population). Indeed, when these patients are excluded from subgroup analysis, the harmful effect of Ivabradine among patients with severe angina disappears. In conclusion, heart rate is a marker of risk but is not a risk factor and/or a target of therapy in patients with stable coronary artery disease and preserved ventricular systolic function. Standard doses of ivabradine are indicated for treatment of angina as an alternative or in addition to beta-blockers, but should not be administered in association with CYP3A4 inhibitors or heart rate-lowering calcium-channel blockers
ARB-based combination therapy for the clinical management of hypertension and hypertension-related comorbidities: a spotlight on their use in COVID-19 patients
Essential hypertension is the most common cardiovascular (CV) risk factor, being primarily involved in the pathogenesis of CV disease and mortality worldwide. Given the high prevalence and growing incidence of this clinical condition in the general population in both high and low-income countries, antihypertensive drug therapies are frequently prescribed in different hypertension-related CV diseases and comorbidities. Among these conditions, evidence are available demonstrating the clinical benefits of lowering blood pressure (BP) levels, particularly in those hypertensive patients at high or very high CV risk profile. Preliminary studies, performed during the Sars-COVID-19 epidemic, raised some concerns on the potential implication of hypertension and antihypertensive medications in the susceptibility of having severe pneumonia, particularly with regard to the use of drugs inhibiting the renin-angiotensin system (RAS), including angiotensin converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs). These hypotheses were not confirmed by subsequent studies, which independently and systematically demonstrated no clinical harm of these drugs also in patients with Sars-COVID-19 infection. The aim of this narrative review is to critically discuss the available evidence supporting the use of antihypertensive therapies based RAS blocking agents in hypertensive patients with different CV risk profile and with additional clinical conditions or comorbidities, including Sars-COVID-19 infection, with a particular focus on single-pill combination therapies based on olmesartan medoxomil
Would You Prescribe Mobile Health Apps for Heart Failure Self-care? An Integrated Review of Commercially Available Mobile Technology for Heart Failure Patients
Treatment of chronic diseases, such as heart failure, requires complex protocols based on early diagnosis; self-monitoring of symptoms, vital signs and physical activity; regular medication intake; and education of patients and caregivers about relevant aspects of the disease. Smartphones and mobile health applications could be very helpful in improving the efficacy of such protocols, but several barriers make it difficult to fully exploit their technological potential and produce clear clinical evidence of their effectiveness. App suppliers do not help users distinguish between useless/dangerous apps and valid solutions. The latter are few and often characterised by rapid obsolescence, lack of interactivity and lack of authoritative information. Systematic reviews can help physicians and researchers find and assess the 'best candidate solutions' in a repeatable manner and pave the way for well-grounded and fruitful discussion on their clinical effectiveness. To this purpose, the authors assess 10 apps for heart failure self-care using the Intercontinental Marketing Statistics score and other criteria, discuss the clinical effectiveness of existing solutions and identify barriers to their use in practice and drivers for change
Monitoring of hadrontherapy treatments by means of charged particle detection
The interaction of the incoming beam radiation with the patient body in hadrontherapy
treatments produces secondary charged and neutral particles, whose detection can be
used for monitoring purposes and to perform an on-line check of beam particle range. In
the context of ion-therapy with active scanning, charged particles are potentially attractive
since they can be easily tracked with a high efficiency, in presence of a relatively low
background contamination. In order to verify the possibility of exploiting this approach
for in-beam monitoring in ion-therapy, and to guide the design of specific detectors, both
simulations and experimental tests are being performed with ion beams impinging on
simple homogeneous tissue-like targets (PMMA). From these studies, a resolution of the
order of few millimeters on the single track has been proven to be sufficient to exploit
charged particle tracking for monitoring purposes, preserving the precision achievable
on longitudinal shape. The results obtained so far show that the measurement of charged
particles can be successfully implemented in a technology capable of monitoring both
the dose profile and the position of the Bragg peak inside the target and finally lead to
the design of a novel profile detector. Crucial aspects to be considered are the detector
positioning, to be optimized in order to maximize the available statistics, and the capability
of accounting for the multiple scattering interactions undergone by the charged
fragments along their exit path from the patient body. The experimental results collected
up to now are also valuable for the validation of Monte Carlo simulation software tools
and their implementation in Treatment Planning Software packages
Genome and transcriptome of the regeneration-competent flatworm, Macrostomum lignano.
The free-living flatworm, Macrostomum lignano has an impressive regenerative capacity. Following injury, it can regenerate almost an entirely new organism because of the presence of an abundant somatic stem cell population, the neoblasts. This set of unique properties makes many flatworms attractive organisms for studying the evolution of pathways involved in tissue self-renewal, cell-fate specification, and regeneration. The use of these organisms as models, however, is hampered by the lack of a well-assembled and annotated genome sequences, fundamental to modern genetic and molecular studies. Here we report the genomic sequence of M. lignano and an accompanying characterization of its transcriptome. The genome structure of M. lignano is remarkably complex, with âŒ75% of its sequence being comprised of simple repeats and transposon sequences. This has made high-quality assembly from Illumina reads alone impossible (N50=222 bp). We therefore generated 130Ă coverage by long sequencing reads from the Pacific Biosciences platform to create a substantially improved assembly with an N50 of 64 Kbp. We complemented the reference genome with an assembled and annotated transcriptome, and used both of these datasets in combination to probe gene-expression patterns during regeneration, examining pathways important to stem cell function.This work is supported by National Institutes of Health Grants R37 GM062534 (to G.J.H.) and R01-HG006677 (to M.S.); National Science Foundation Grant DBI-1350041 (to M.S.); and a Swiss National Science Foundation Grant 31003A-143732 (to L.S.). This work was performed with assistance from Cold Spring Harbor Laboratory Shared Resources, which are funded, in part, by Cancer Center Support Grant 5P30CA045508.This is the final version of the article. It first appeared from PNAS via http://dx.doi.org/10.1073/pnas.151671811
Localization of anatomical changes in patients during proton therapy with in-beam PET monitoring: a voxel-based morphometry approach exploiting Monte Carlo simulations
Purpose: In-beam positron emission tomography (PET) is one of the modalities that can be used for in vivo noninvasive treatment monitoring in proton therapy. Although PET monitoring has been frequently applied for this purpose, there is still no straightforward method to translate the information obtained from the PET images into easy-to-interpret information for clinical personnel. The purpose of this work is to propose a statistical method for analyzing in-beam PET monitoring images that can be used to locate, quantify, and visualize regions with possible morphological changes occurring over the course of treatment. Methods: We selected a patient treated for squamous cell carcinoma (SCC) with proton therapy, to perform multiple Monte Carlo (MC) simulations of the expected PET signal at the start of treatment, and to study how the PET signal may change along the treatment course due to morphological changes. We performed voxel-wise two-tailed statistical tests of the simulated PET images, resembling the voxel-based morphometry (VBM) method commonly used in neuroimaging data analysis, to locate regions with significant morphological changes and to quantify the change. Results: The VBM resembling method has been successfully applied to the simulated in-beam PET images, despite the fact that such images suffer from image artifacts and limited statistics. Three dimensional probability maps were obtained, that allowed to identify interfractional morphological changes and to visualize them superimposed on the computed tomography (CT) scan. In particular, the characteristic color patterns resulting from the two-tailed statistical tests lend themselves to trigger alarms in case of morphological changes along the course of treatment. Conclusions: The statistical method presented in this work is a promising method to apply to PET monitoring data to reveal interfractional morphological changes in patients, occurring over the course of treatment. Based on simulated in-beam PET treatment monitoring images, we showed that with our method it was possible to correctly identify the regions that changed. Moreover we could quantify the changes, and visualize them superimposed on the CT scan. The proposed method can possibly help clinical personnel in the replanning procedure in adaptive proton therapy treatments
In-vivo range verification analysis with in-beam PET data for patients treated with proton therapy at CNAO
Morphological changes that may arise through a treatment course are probably one of the most significant sources of range uncertainty in proton therapy. Non-invasive in-vivo treatment monitoring is useful to increase treatment quality. The INSIDE in-beam Positron Emission Tomography (PET) scanner performs in-vivo range monitoring in proton and carbon therapy treatments at the National Center of Oncological Hadrontherapy (CNAO). It is currently in a clinical trial (ID: NCT03662373) and has acquired in-beam PET data during the treatment of various patients. In this work we analyze the in-beam PET (IB-PET) data of eight patients treated with proton therapy at CNAO. The goal of the analysis is twofold. First, we assess the level of experimental fluctuations in inter-fractional range differences (sensitivity) of the INSIDE PET system by studying patients without morphological changes. Second, we use the obtained results to see whether we can observe anomalously large range variations in patients where morphological changes have occurred. The sensitivity of the INSIDE IB-PET scanner was quantified as the standard deviation of the range difference distributions observed for six patients that did not show morphological changes. Inter-fractional range variations with respect to a reference distribution were estimated using the Most-Likely-Shift (MLS) method. To establish the efficacy of this method, we made a comparison with the Beam's Eye View (BEV) method. For patients showing no morphological changes in the control CT the average range variation standard deviation was found to be 2.5 mm with the MLS method and 2.3 mm with the BEV method. On the other hand, for patients where some small anatomical changes occurred, we found larger standard deviation values. In these patients we evaluated where anomalous range differences were found and compared them with the CT. We found that the identified regions were mostly in agreement with the morphological changes seen in the CT scan
FOOT: a new experiment to measure nuclear fragmentation at intermediate energies
Summary: Charged particle therapy exploits proton or 12C beams to treat deep-seated solid tumors. Due to the advantageous characteristics of charged particles energy deposition in matter, the maximum of the dose is released to the tumor at the end of the beam range, in the Bragg peak region. However, the beam nuclear interactions with the patient tissues induces fragmentation both of projectile and target nuclei and needs to be carefully taken into account. In proton treatments, target fragmentation produces low energy, short range fragments along all the beam range, which deposit a non negligible dose in the entry channel. In 12C treatments the main concern is represented by long range fragments due to beam fragmentation that release their dose in the healthy tissues beyond the tumor. The FOOT experiment (FragmentatiOn Of Target) of INFN is designed to study these processes, in order to improve the nuclear fragmentation description in next generation Treatment Planning Systems and the treatment plans quality. Target (16O and 12C nuclei) fragmentation induced by âproton beams at therapeutic energies will be studied via an inverse kinematic approach, where 16O and 12C therapeutic beams impinge on graphite and hydrocarbon targets to provide the nuclear fragmentation cross section on hydrogen. Projectile fragmentation of 16O and 12C beams will be explored as well. The FOOT detector includes a magnetic spectrometer for the fragments momentum measurement, a plastic scintillator for ÎE and time of flight measurements and a crystal calorimeter to measure the fragments kinetic energy. These measurements will be combined in order to make an accurate fragment charge and isotopic identification. Keywords: Hadrontherapy, Nuclear fragmentation cross sections, Tracking detectors, Scintillating detector
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