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Atrial fibrillation (AF) is an arrhythmia that occurs as a result of numerous pathophysiological processes in the atria. High rate, neurohumoral activation, aging and chronic stretch activate a variety of signaling pathways leading to electrical and structural remodeling. In particular, endomysial fibrosis within the epicardial layer, which also occurs as a result of AF itself, can disrupt electrical connections between muscle bundles. This leads to electrical dissociation not only within the epicardial layer, but also between the epicardial layer and the endocardial bundle network. Although the normal, healthy atrium has a complex 3-dimensional shape, differences in activation time between the epicardial layer and the underlying trabecular network in the atrial free walls are small, and the atrial walls essentially function as a 2-dimensional surface for propagating fibrillation waves. However, progressive structural remodeling leads to increased dissociation of epicardial and endocardial activation patterns. Epi-endocardial dissociation allows fibrillation waves to propagate between epicardium and endocardium, and become visible as ‘breakthrough waves’ that add to the overall complexity of fibrillatory conduction and thus to AF stability. This process greatly increases the effective surface area available to fibrillation waves and causes the atrial walls to behave as a 3-dimensional substrate. Computer models support that this behavior can increase AF stability. Under these conditions, ectopic activity originating from e.g. the pulmonary veins is likely to trigger longer episodes of AF. Experiments using simultaneous endo-epicardial mapping of AF suggest that disseminated, irregular and non-repetitive ectopic focal discharges might also occur during AF. The increasingly 3-dimensional character of AF as a result of structural remodeling lowers the responsiveness to antiarrhythmic compounds and ablation therapy, thus advocating early rhythm control strategies. [ABSTRACT FROM AUTHOR]

Our present knowledge about cardiac electrophysiology is based on numerous experiments and discoveries going back to the Greek antique and ancient Egypt. Exploration of cardiac anatomy was followed by the description of circulation and cardiac physiology in the 17th century. In the early 20th century cardiac electrophysiology became the new field of interest and was studied with the help of numerous animal experiments (squid, rays, dogs, goats, mice and other species). We ought to be grateful for the knowledge and possibilities in modern medicine that were made possible by the great number of researchers, patients and animals that contributed to this. [ABSTRACT FROM AUTHOR]

Objectives: Due to different release mechanisms, midregional pro-atrial natriuretic peptide (MR proANP) may be superior to N-terminal pro-B-type natriuretic peptide (NT proBNP) in the diagnosis of acute heart failure (AHF) in patients with atrial fibrillation (AF). We compared MR proANP and NT proBNP for their diagnostic value in patients with AF and sinus rhythm (SR). Design: Prospective cohort study. Setting: University hospital, emergency department. Patients: 632 consecutive patients presenting with acute dyspnoea. Main outcome measures: MR proANP and NT proBNP plasma levels were determined. The diagnosis of AHF was adjudicated by two independent cardiologists using all available data. Patients received long-term follow-up. Results: AF was present in 151 patients (24%). MR proANP and NT proBNP levels were significantly higher in the AF group compared with the SR group (385 (258e598) versus 201 (89e375) pmol/l for MR proANP, p<0.001 and 4916 (2169e10285) versus 1177 (258e5166) pg/ml, p<0.001 for NT proBNP). Diagnostic accuracy in AF patients was similar for MR proANP (0.90, 95% CI 0.84 to 0.95) and NT proBNP (0.89, 95% CI 0.81 to 0.96). Optimal cut-off levels in AF patients were significantly higher compared with the optimal cutoff levels for patients in SR (MR proANP 240 vs 200 pmol/l; NT proBNP 2670 vs 1500 pg/ml respectively). After adjustment in multivariable Cox proportional hazard analysis, MR proANP strongly predicted one-year all-cause mortality (HR¼1.13 (1.09e1.17), per 100 pmol/l increase, p<0.001). Conclusion: In AF patients, NT proBNP and MR proANP have similar diagnostic value for the diagnosis of AHF. The rhythm at presentation has to be taken into account because plasma levels of both peptides are significantly higher in patients with AF compared with SR. [ABSTRACT FROM AUTHOR]

Aims This study aims to determine the degree and mechanisms of endo-epicardial dissociation of electrical activity during atrial fibrillation (AF) and endo-epicardial differences in atrial electrophysiology at different stages of atrial remodelling. Methods and results Simultaneous high-density endo-epicardial mapping of AF was performed on left atrial free walls of goats with acute AF, after 3 weeks, and after 6 months of AF (all n = 7). Endo-epicardial activation time differences and differences in the direction of conduction vectors were calculated, endocardial and epicardial effective refractory periods (ERP) were determined, and fractionation of electrograms was quantified. Histograms of endo-epicardial activation time differences and differences in the direction of conduction vectors revealed two distinct populations, i.e. dissociated and non-dissociated activity. Dyssynchronous activity (dissociated in time) increased from 17 ± 7% during acute AF to 39 ± 17% after 3 weeks, and 68 ± 13% after 6 months of AF. Dissociation was more pronounced in thicker parts of the atrial wall (thick: 49.3 ± 21.4%, thin: 42.2 ± 19.0%, P < 0.05). At baseline, endocardial ERPs were longer when compared with epicardial ERPs (ΔERP, 21.8 ± 18 ms; P < 0.001). This difference was absent after 6 months of AF. The percentage of fractionated electrograms during rapid pacing increased from 9.4 ± 1.9% (baseline) to 18.6 ± 0.6% (6 months). Conclusion During AF, pronounced dissociation of electrical activity occurs between the epicardial layer and the endocardial bundle network. The increase in dissociation is due to owing to progressive uncoupling between the epicardial layer and the endocardial bundles and correlates with increasing stability and complexity of the AF substrate. [ABSTRACT FROM AUTHOR]

Abstract: The progressive nature of atrial fibrillation (AF) has been demonstrated in numerous experimental as well as clinical investigations. Electrical remodeling (shortening of atrial refractoriness) develops within the first days of AF and contributes to the increase in stability of the arrhythmia. However, “domestication of AF” must also depend on other mechanisms since the stability of AF continues to increase after electrical remodeling has been completed. Chronic atrial stretch induces activation of numerous signaling pathways leading to cellular hypertrophy, fibroblast proliferation and tissue fibrosis. The resulting electro-anatomical substrate is characterized by increased non-uniform anisotropy and local conduction heterogeneities facilitating reentry in the dilated atria. Atrial fibrosis may lead to disruption of the electrical side-to-side junctions between muscle bundles. This can result in electrical dissociation between neighboring muscle bundles, i.e. they become activated out-of-phase. Recent mapping studies in goats with persistent AF showed that electrical dissociation can not only occur between neighboring muscle bundles but also in the third dimension, i.e. between the epicardial layer and the endocardial bundle network. Such endo-epicardial dissociation will significantly increase the number of wavefronts which can simultaneously be present in the atrial wall. This article reviews data suggesting a role of endo-epicardial dissociation in dilated and fibrillating atria, for the self-perpetuating nature of AF as well as its possible implications for therapeutic interventions. [Copyright &y& Elsevier]

Discusses the inhibition of thymidylate synthase (TS) from Lactobacillus casei by 5-(trifluoromethyl)-2'-deoxyuridine 5'-monophosphate (CF3dUMP). Binding of CF3dUMP to the active site of TS in the absence of 5,10-methylenetetrahydrofolate; Activation of the trifluoromethyl group and release of the fluoride ion; Formation of a moderately stable covalent complex.

The silent pandemic of bacterial antimicrobial resistance is a leading cause of death worldwide, prolonging hospital stays and raising health-care costs. Poor incentives to develop novel pharmacological compounds and the misuse of antibiotics contribute to the bacterial antimicrobial resistance crisis. Therapeutic drug monitoring (TDM) based on blood analysis can help alleviate the emergence of bacterial antimicrobial resistance and effectively decreases the risk of toxic drug concentrations in patients' blood. Antibiotic tissue penetration can vary in patients who are critically or chronically ill and can potentially lead to treatment failure. Antibiotics such as β-lactams and glycopeptides are detectable in non-invasively collectable biofluids, such as sweat and exhaled breath. The emergence of wearable sensors enables easy access to these non-invasive biofluids, and thus a laboratory-independent analysis of various disease-associated biomarkers and drugs. In this Personal View, we introduce a three-level model for TDM of antibiotics to describe concentrations at the site of infection (SOI) by use of wearable sensors. Our model links blood-based drug measurement with the analysis of drug concentrations in non-invasively collectable biofluids stemming from the SOI to characterise drug concentrations at the SOI. Finally, we outline the necessary clinical and technical steps for the development of wearable sensing platforms for SOI applications. [ABSTRACT FROM AUTHOR]

Core body temperature (CBT) is a key vital sign and fever is an important indicator of disease. In the past decade, there has been growing interest for vital sign monitoring technology that may be embedded in wearable devices, and the COVID-19 pandemic has highlighted the need for remote patient monitoring systems. While wrist-worn sensors allow continuous assessment of heart rate and oxygen saturation, reliable measurement of CBT at the wrist remains challenging. In this study, CBT was measured continuously in a free-living setting using a novel technology worn at the wrist and compared to reference core body temperature measurements, i.e., CBT values acquired with an ingestible temperature-sensing pill. Fifty individuals who received the COVID-19 booster vaccination were included. The datasets of 33 individuals were used to develop the CBT prediction algorithm, and the algorithm was then validated on the datasets of 17 participants. Mean observation time was 26.4 h and CBT > 38.0 °C occurred in 66% of the participants. CBT predicted by the wrist-worn sensor showed good correlation to the reference CBT (r = 0.72). Bland–Altman statistics showed an average bias of 0.11 °C of CBT predicted by the wrist-worn device compared to reference CBT, and limits of agreement were − 0.67 to + 0.93 °C, which is comparable to the bias and limits of agreement of commonly used tympanic membrane thermometers. The small size of the components needed for this technology would allow its integration into a variety of wearable monitoring systems assessing other vital signs and at the same time allowing maximal freedom of movement to the user. [ABSTRACT FROM AUTHOR]

Introduction: This study investigates the accuracy of a heart rate (HR) measurement algorithm applied to a pulse wave. This was based on video signals recorded with a smartphone. The results of electrocardiographic HR and standard linear heart rate variability (HRV) analysis were used for reference. Materials and Methods: On a total of 68 subjects, an electrocardiogram (ECG) and the pulse curve were simultaneously recorded on an Apple iPhone 4S. The HR was measured using an algorithm developed by the authors that works according to a method combining the detection of the steepest slope of every pulse wave with the correlation to an optimized pulse wave pattern. Results: The results of the HR measured by pulse curves were extremely consistent (R> 0.99) with the HR measured on ECGs. For most standard linear HRV parameters as well, high correlations of R≥ 0.90 in the analysis were achieved in the time and frequency domain. Conclusion: In conclusion, the overall accuracy of HR and HRV indices of pulse wave analysis, based on video signals of a smartphone, with the developed algorithm was sufficient for preclinical screening applications. [ABSTRACT FROM AUTHOR]

Background: While effectiveness outcomes of eHealth-facilitated integrated care models (eICMs) in transplant and oncological populations are promising, implementing and sustaining them in real-world settings remain challenging. Allogeneic stem cell transplant (alloSCT) patients could benefit from an eICM to enhance health outcomes. To combat health deterioration, integrating chronic illness management, including continuous symptom and health behaviour monitoring, can shorten reaction times. We will test the 1st-year post-alloSCT effectiveness and evaluate bundled implementation strategies to support the implementation of a newly developed and adapted eICM in allogeneic stem cell transplantation facilitated by eHealth (SMILe-ICM). SMILe-ICM has been designed by combining implementation, behavioural, and computer science methods. Adaptions were guided by FRAME and FRAME-IS. It consists of four modules: 1) monitoring & follow-up; 2) infection prevention; 3) physical activity; and 4) medication adherence, delivered via eHealth and a care coordinator (an Advanced Practice Nurse). The implementation was supported by contextually adapted implementation strategies (e.g., creating new clinical teams, informing local opinion leaders).Methods: Using a hybrid effectiveness-implementation randomised controlled trial, we will include a consecutive sample of 80 adult alloSCT patients who were transplanted and followed by University Hospital Basel (Switzerland). Inclusion criteria are basic German proficiency; elementary computer literacy; internet access; and written informed consent. Patients will be excluded if their condition prevents the use of technology, or if they are followed up only at external centres. Patient-level (1:1) stratified randomisation into a usual care group and a SMILe-ICM group will take place 10 days pre-transplantation. To gauge the SMILe-ICM's effectiveness primary outcome (re-hospitalisation rate), secondary outcomes (healthcare utilization costs; length of inpatient re-hospitalizations, medication adherence; treatment and self-management burden; HRQoL; Graft-versus-Host Disease rate; survival; overall survival rate) and implementation outcomes (acceptability, appropriateness, feasibility, fidelity), we will use multi-method, multi-informant assessment (via questionnaires, interviews, electronic health record data, cost capture methods).Discussion: The SMILe-ICM has major innovative potential for reengineering alloSCT follow-up care, particularly regarding short- and medium-term outcomes. Our dual focus on implementation and effectiveness will both inform optimization of the SMILe-ICM and provide insights regarding implementation strategies and pathway, understudied in eHealth-facilitated ICMs in chronically ill populations.Trial Registration: ClinicalTrials.gov. Identifier: NCT04789863 . Registered April 01, 2021. [ABSTRACT FROM AUTHOR]

(1) Background: New cuffless technologies attempting blood-pressure measurements (BPM) offer possibilities to improve hypertension awareness and control. The aim of this study was to compare a smartphone application (app)-based algorithm with office BPM (OBPM). (2) Methods: We included consecutive patients with an indication for ambulatory BPM. The smartphone app (RIVA digital) acquired the pulse wave in the fingers' arterial bed using the phone's camera and estimated BP based on photoplethysmographic (PPG) waveforms. Measurements were alternatingly taken with an oscillometric cuff-based device and smartphone BPM (AppBP) on two consecutive days. AppBP were calibrated to the first OBPM. Each AppBP was compared to its CuffBP (mean of the previous/following OBPM). (3) Results: 50 participants were included, resulting in 50 AppBP values on Day 1 and 33 on Day 2 after exclusion of 225 AppBP due to insufficient quality. The mean ± SD of the differences between AppBP and CuffBP was 0.7 ± 9.4/1.0 ± 4.5 mmHg (p-value 0.739/0.201) on Day 1 and 2.6 ± 8.2/1.3 ± 4.1 mmHg (p-value 0.106/0.091) on Day 2 for systolic/diastolic values, respectively. There were no significant differences between the deviations on Day 1 and Day 2 (p-value 0.297/0.533 for systolic/diastolic values). Overall, there were 10 (12%) systolic measurement pairs differing by >15 mmHg. (4) Conclusions: In this pilot evaluation, the RIVA Digital app shows promising results when compared to oscillometric cuff-based measurements, especially regarding diastolic values. Its differences between AppBP–CuffBP have a good stability one day after calibration. Before clinical use, signal acquisition needs improvement and the algorithm needs to undergo formal validation against a gold-standard BPM method. [ABSTRACT FROM AUTHOR]

Background: Although bedside case presentation contributes to patient-centered care through active patient participation in medical discussions, the complexity of medical information and jargon-induced confusion may cause misunderstandings and patient discomfort.Objective: To compare bedside versus outside the room patient case presentation regarding patients' knowledge about their medical care.Design: Randomized, controlled, parallel-group trial. (ClinicalTrials.gov: NCT03210987).Setting: 3 Swiss teaching hospitals.Patients: Adult medical patients who were hospitalized.Intervention: Patients were randomly assigned to bedside or outside the room case presentation.Measurements: The primary endpoint was patients' average knowledge of 3 dimensions of their medical care (each rated on a visual analogue scale from 0 to 100): understanding their disease, the therapeutic approach being used, and further plans for care.Results: Compared with patients in the outside the room group (n = 443), those in the bedside presentation group (n = 476) reported similar knowledge about their medical care (mean, 79.5 points [SD, 21.6] vs. 79.4 points [SD, 19.8]; adjusted difference, 0.09 points [95% CI, -2.58 to 2.76 points]; P = 0.95). Also, an objective rating of patient knowledge by the study team was similar for the 2 groups, but the bedside presentation group had higher ratings of confusion about medical jargon and uncertainty caused by team discussions. Bedside ward rounds were more efficient (mean, 11.89 minutes per patient [SD, 4.92] vs. 14.14 minutes per patient [SD, 5.65]; adjusted difference, -2.31 minutes [CI, -2.98 to -1.63 minutes]; P < 0.001).Limitation: Only Swiss hospitals and medical patients were included.Conclusion: Compared with outside the room case presentation, bedside case presentation was shorter and resulted in similar patient knowledge, but sensitive topics were more often avoided and patient confusion was higher. Physicians presenting at the bedside need to be skilled in the use of medical language to avoid confusion and misunderstandings.Primary Funding Source: Swiss National Foundation (10531C_ 182422). [ABSTRACT FROM AUTHOR]

Background:Atrial fibrillation (AF), the most common cardiac arrhythmia, can be detected by smartphones and smartwatches. Introduction:Single-lead ECGs (iECGs) and photoplethysmography (PPG) sensors provide the opportunity for a broad, simple, and easily repeatable cardiac rhythm analysis. To reduce unnecessary medical follow-up testing due to false positive results, our aim was to find a screening approach applicable on smart devices with a focus on high specificity. Methods:We used PPG measurements from smartphones and smartwatches and iECG data from two previous validation trials. Two AF detection algorithms (A and B) were applied on the iECG dataset and compared directly. Further, we used 1-min PPG measurements as a first-pass filter for arrhythmia detection and simulated a sequential testing: Once an arrhythmia was detected in the PPG, the iECG counterpart of the patient was analyzed by algorithm A, B, or A + B combined although algorithm B was primarily designed for PPG analysis. Results:The iECGs from 1,288 participants were analyzed. Algorithm A did not show a diagnosis in 16.1%. In the remaining, sensitivity and specificity were 99.6%, and 97.4% respectively. Accuracy was 98.5%, and correct classification rate (CCR) was 82.7%. Algorithm B always differentiated between normal and arrhythmic and reached an overall sensitivity of 95.4%, a specificity of 91.6%, and an accuracy and CCR of 93.3%. Sequential testing by combining both algorithms into a three-phase test (Test positive PPG, then iECG analysis by A and B combined) resulted in a 100% specificity. Conclusion:Algorithm B performed strongly in PPG analysis as well as iECG analysis. PPG signals and consecutive iECG combined when an arrhythmia was detected by PPG resulted in a specificity that was higher than 99%. Discussion:The analysis allows a direct comparison of iECG algorithms without possible dilution by different measurement procedures or recording-devices. We improved specificity in AF-screening approaches with wearables by simulating a novel approach. Results rely on signal quality. [ABSTRACT FROM AUTHOR]

According to the European Hypertension Guidelines regarding office blood pressure measurements (OBPMs), the mean between second/third or third/fourth OBPM should be taken if the first two readings differ by ≤10 or >10 mmHg, respectively. Our aim was to explore the value of the fourth OBPM and determine whether a simplified OBPM procedure is feasible without loss of quality. In this cross‐sectional study, four standard OBPMs were taken. The mean of the second/third OBPM (S2S3/D2D3) and third/fourth OBPM (S3S4/D3D4) for systolic/diastolic values was calculated. Correlation, agreement, and differences regarding BP classification were explored for the entire cohort and subsets with a difference between the first/second OBPM (S1S2/D1D2) ≤10 and >10 mmHg. Overall (n = 802) and for the subsets with an S1S2 (n = 596) and D1D2 (n = 742) difference ≤10 mmHg, S3S4/D3D4 was in median 0.5 mmHg lower than S2S3/D2D3, respectively (p <.0005 for all). In participants with an S1S2 (n = 206) and D1D2 (n = 60) difference >10 mmHg, S3S4/D3D4 differed numerically from S2S3/D2D3, respectively (p >.1 for all). Overall and for all subsets with an S1S2/D1D2 difference ≤10/>10 mmHg, less subjects were numerically classified as hypertensive with S3S4/D3D4 than with S2S3/D2D3 (p >.04), but BP reclassification occurred in both directions in 1.0%‐10.0%, depending on the cohort. In conclusion, the third/fourth OBPM results in lower BP values than the second/third measurement, regardless of the difference between first/second OBPM, whereby BP reclassifications occurred in both directions. Therefore, the cutoff of >10 versus ≤10mmHg difference between first/second OBPM to implement a fourth BPM harbors the risk of distorted results. We therefore recommend using the second/third BPM for standardized OBPM. Trial registration: Registered on clinicaltrials.gov (NCT02552030). [ABSTRACT FROM AUTHOR]

Abstract: Background and methods: Atrial fibrillation (AF) is the most common cardiac arrhythmia in clinical practice. The substrate of AF is composed of a complex interplay between structural and functional changes of the atrial myocardium often preceding the occurrence of persistent AF. However, there are only few animal models reproducing the slow progression of the AF substrate to the spontaneous occurrence of the arrhythmia. Transgenic mice (TG) with cardiomyocyte-directed expression of CREM-IbΔC-X, an isoform of transcription factor CREM, develop atrial dilatation and spontaneous-onset AF. Here we tested the hypothesis that TG mice develop an arrhythmogenic substrate preceding AF using physiological and biochemical techniques. Results: Overexpression of CREM-IbΔC-X in young TG mice (<8weeks) led to atrial dilatation combined with distension of myocardium, elongated myocytes, little fibrosis, down-regulation of connexin 40, loss of excitability with a number of depolarized myocytes, atrial ectopies and inducibility of AF. These abnormalities continuously progressed with age resulting in interatrial conduction block, increased atrial conduction heterogeneity, leaky sarcoplasmic reticulum calcium stores and the spontaneous occurrence of paroxysmal and later persistent AF. This distinct atrial remodelling was associated with a pattern of non-regulated and up-regulated marker genes of myocardial hypertrophy and fibrosis. Conclusions: Expression of CREM-IbΔC-X in TG hearts evokes abnormal growth and development of the atria preceding conduction abnormalities and altered calcium homeostasis and the development of spontaneous and persistent AF. We conclude that transcription factor CREM is an important regulator of atrial growth implicated in the development of an arrhythmogenic substrate in TG mice. [Copyright &y& Elsevier]

Background: Loss of left ventricular capture in patients with cardiac resynchronization devices may account for worsening heart failure and can be difficult to diagnose without a programmer.Objective: To determine whether distinct morphologic changes on the surface electrocardiogram indicate loss of left ventricular capture.Design: After analysis of the R-S spike ratio in the 12-lead electrocardiogram during right ventricular and biventricular pacing in 10 patients, an algorithm to detect loss of left ventricular capture was developed.Setting: University hospital.Patients: 54 patients with a cardiac resynchronization device and underlying left bundle-branch block.Measurements: Leads V1 and I of a 12-lead electrocardiogram were assessed after biventricular pacing was confirmed and after the device was programmed to right ventricular pacing only (simulating loss of left ventricular capture).Results: The sensitivity of the algorithm to correctly identify loss of left ventricular capture was 94% (95% CI, 88.2% to 97.7%), and the specificity was 93% (CI, 86.3% to 95.8%). The likelihood ratio of a positive test result was 12.8 (CI, 6.443 to 23.310), and the likelihood ratio of a negative test result was 0.06 (CI, 0.024 to 0.137).Limitations: The algorithm was tested in patients in whom the right ventricular electrode was placed in the apex of the right ventricle only.Conclusion: Presence of biventricular capture--the prerequisite for successful cardiac resynchronization therapy--and loss of left ventricular capture can be accurately detected by an algorithm based on analysis of the R-S ratio on leads V1 and I of the surface electrocardiogram. [ABSTRACT FROM AUTHOR]

Background: Loss of left ventricular capture in patients with cardiac resynchronization devices may account for worsening heart failure and can be difficult to diagnose without a programmer. Objective: To determine whether distinct morphologic changes on the surface electrocardiogram indicate loss of left ventricular capture. Design: After analysis of the R-S spike ratio in the 12-lead electrocardiogram during right ventricular and biventricular pacing in 10 patients, an algorithm to detect loss of left ventricular capture was developed. Setting: University hospital. Patients: 54 patients with a cardiac resynchronization device and underlying left bundle-branch block. Measurements: Leads V1 and I of a 12-lead electrocardiogram were assessed after biventricular pacing was confirmed and after the device was programmed to right ventricular pacing only (simulating loss of left ventricular capture). Results: The sensitivity of the algorithm to correctly identify loss of left ventricular capture was 94% (95% CI, 88.2% to 97.7%), and the specificity was 93% (CI, 86.3% to 95.8%). The likelihood ratio of a positive test result was 12.8 (CI, 6.443 to 23.310), and the likelihood ratio of a negative test result was 0.06 (CI, 0.024 to 0.137). Limitations: The algorithm was tested in patients in whom the right ventricular electrode was placed in the apex of the right ventricle only. Conclusion: Presence of biventricular capture the prerequisite for successful cardiac resynchronization therapy-and loss of left ventricular capture can be accurately detected by an algorithm based on analysis of the R-S ratio on leads V1 and I of the surface electrocardiogram. [ABSTRACT FROM AUTHOR]

Objectives: We aimed to compare the hemodynamic effects of right-atrial-paced (DDD) and right-atrial-sensed (VDD) biventricular paced rhythm on cardiac resynchronization therapy (CRT). Background: Cardiac resynchronization therapy improves hemodynamics in patients with severe heart failure and left ventricular (LV) dyssynchrony. However, the impact of active right atrial pacing on resynchronization therapy is unknown. Methods: Seventeen CRT patients were studied 10 months (range: 1 to 46 months) after implantation. At baseline, the programmed atrioventricular delay was optimized by timing LV contraction properly at the end of atrial contraction. In both modes the acute hemodynamic effects were assessed by multiple Doppler echocardiographic parameters. Results: Compared to DDD pacing, VDD pacing resulted in much better improvement of intraventricular dyssynchrony assessed by the septal-to-posterior wall motion delay (VDD 106 ± 83 ms vs. DDD 145 ± 95 ms; p = 0.001), whereas the interventricular mechanical delay (difference between onset of pulmonary and aortic outflow) did not differ (VDD 20 ± 21 ms vs. DDD 18 ± 17 ms; p = NS). Furthermore, VDD pacing significantly prolonged the rate-corrected LV filling period (VDD 458 ± 123 ms vs. DDD 371 ± 94 ms; p = 0.0001) and improved the myocardial performance index (VDD 0.60 ± 0.18 vs. DDD 0.71 ± 0.23; p &#60; 0.01). Conclusions: Our findings suggest that avoidance of right atrial pacing results in a higher degree of LV resynchronization, in a substantial prolongation of the LV filling period, and in an improved myocardial performance. Thus, the VDD mode seems to be superior to the DDD mode in CRT patients. [Copyright &y& Elsevier]

Examines the conformational analysis of a stereochemical complete set of cis-enediol peptide analogues. Computation of energy surfaces for all dihedral angle values; Ability of stereoisomers to mimic natural peptides; Determination of the energy surfaces of the peptide analogues.

Background: A comprehensive in-hospital patient management with reasonable and economic resource allocation is arguably the major challenge of health-care systems worldwide, especially in elderly, frail, and polymorbid patients. The need for patient management tools to improve the transition process and allocation of health care resources in routine clinical care particularly for the inpatient setting is obvious. To address these issues, a large prospective trial is warranted.Methods: The "Integrative Hospital Treatment in Older patients to benchmark and improve Outcome and Length of stay" (In-HospiTOOL) study is an investigator-initiated, multicenter effectiveness trial to compare the effects of a novel in-hospital management tool on length of hospital stay, readmission rate, quality of care, and other clinical outcomes using a time-series model. The study aims to include approximately 35`000 polymorbid medical patients over an 18-month period, divided in an observation, implementation, and intervention phase. Detailed data on treatment and outcome of polymorbid medical patients during the in-hospital stay and after 30 days will be gathered to investigate differences in resource use, inter-professional collaborations and to establish representative benchmarking data to promote measurement and display of quality of care data across seven Swiss hospitals. The trial will inform whether the "In-HospiTOOL" optimizes inter-professional collaboration and thereby reduces length of hospital stay without harming subjective and objective patient-oriented outcome markers.Discussion: Many of the current quality-mirroring tools do not reflect the real need and use of resources, especially in polymorbid and elderly patients. In addition, a validated tool for optimization of patient transition and discharge processes is still missing. The proposed multicenter effectiveness trial has potential to improve interprofessional collaboration and optimizes resource allocation from hospital admission to discharge. The results will enable inter-hospital comparison of transition processes and accomplish a benchmarking for inpatient care quality. [ABSTRACT FROM AUTHOR]