P1371Catheter-induced premature ventricular complexes (pvc) may aid in the determination of optimal timing for clinical pvc ablation

EP Europace ◽  
2020 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
S Demir ◽  
T Akgun ◽  
K Gulsen ◽  
A Kup ◽  
A Uslu ◽  
...  
Keyword(s):  
Patient Population ◽  
Premature Ventricular Complex ◽  
Optimal Timing ◽  
Time Interval ◽  
Qrs Complex ◽  
Local Activation ◽  
Premature Ventricular Complexes ◽  
Successful Ablation ◽  
Procedural Success ◽  
The Relationship

Abstract Background There is significant interpatient variability regarding the timing of the earliest local activation relative to surface QRS during premature ventricular complex (PVC) ablation. The aim of the present study is to evaluate whether catheter-induced premature ventricular complexes (PVCs) produced at the presumptive ablation site may aid in the identification of the optimal timing of the earliest local activation for the successful ablation of clinical PVCs. Methods Sixty-three consecutive patients (35 males, age: 53.5 ± 14.4 years) without any exclusion criteria who had undergone PVC ablation between 01/07/2018 and 01/07/2019 constituted our study population.  Catheter-induced PVCs were generated at the site with presumptive PVC origin according to the ECG criteria during the procedure of PVC ablation. Five PVCs were induced by mechanical stimulation in separate points, and the time interval between the beginning of EGM at catheter tracing and the beginning of the QRS complex of each catheter-induced PVC was noted. The mode of five time intervals (Cath EGM-ECG) was used in the analysis. The time interval between the beginning of local EGM of clinical PVCs at the earliest site and the beginning of the QRS complex of clinical PVCs (PVC earliest EGM-ECG) was also noted. The value of Cath EGM-ECG as a reference for procedural success of ablation was evaluated by examining the relationship between Cath EGM-ECG and PVC earliest EGM-ECG. Results Fifty-two patients had successful ablation, and 43 of them (82.7%) had PVC earliest EGM-ECG values greater than or equal to Cath EGM-ECG. Eleven patients had procedural failure, and all of them had PVC earliest EGM-ECG values lower than Cath EGM-ECG (Table 1). A PVC earliest EGM-ECG value -1.5 ms greater than Cath EGM-ECG predicted successful ablation with a sensitivity of 90.4% and a specificity of 100.0% in the general patient population (Figure 1). Conclusion The results of the present study indicate that catheter-induced PVCs generated at the site of the presumptive source of origin of clinical PVCs may guide the timing of the earliest site during clinical PVC ablation. Further studies are required to validate our results and test the predictive value of Cath EGM- ECG interval for long-term success of PVC ablation. Table 1 PVC earliest EGM-ECG < Cath EGM- ECG PVC earliest EGM-ECG ≥ Cath EGM- ECG Ablation successful (n:52) 9 (17.3%) 43 (82.7%) Ablation not successful (n:11) 11 (100.0%) 0 (0%) Outcome of ablation in general patient population according to the relationship between PVC earliest EGM-ECG and Cath EGM- ECG Abstract Figure 1

A PVC BEATS RECOGNITION USING FUZZY CLASSIFIER

2010 ◽  
Vol 10 (02) ◽  
pp. 327-339
Author(s):  
M. A. CHIKH ◽  
OMAR BEHADADA
Keyword(s):  
Qrs Complex ◽  
Fuzzy Classifier ◽  
Premature Ventricular Complexes ◽  
Rr Interval

This article describes a fuzzy classifier for the identification of premature ventricular complexes (PVCs) in surface electrocardiograms (ECGs). The classifier uses features extracted from the ECG beat, such as the width of QRS complex and RR interval. The performance of the algorithm is evaluated on the MIT-BIH Arrhythmia Database following the AAMI recommendations. The results of the experiments of the recognition of PVCs have confirmed the reliability and advantage of the proposed approach.

scholarly journals Impact of diet on the immunological microenvironment of the pregnant uterus and its relationship to allergic disease in the offspring: a review of the recent literature

2006 ◽  
Vol 124 (5) ◽  
pp. 298-303 ◽  
Author(s):  
Daniella Campelo Batalha Cox Moore ◽  
Pedro Xavier Elsas ◽  
Elisabeth Santos Maximiano ◽  
Maria Ignez Capella Gaspar Elsas
Keyword(s):  
Allergic Disease ◽  
Allergic Diseases ◽  
Perinatal Period ◽  
Time Interval ◽  
Industrialized Countries ◽  
Pregnant Uterus ◽  
Medical Progress ◽  
Immunological Profile ◽  
Dietary Content ◽  
The Relationship

Medical progress has reduced the mortality from infectious diseases in most countries, but allergic diseases have become more prevalent worldwide over the same period, especially in industrialized countries. This has prompted speculation that modern lifestyles have altered the relationship between heredity and environment so as to promote development of an atopic phenotype when exposure to infection decreases. A healthy uterine microenvironment is known to favor Th2 lymphocyte development. However, some evidence suggests that persistence of the Th2 pattern of immunity directs the developing organism's immune response towards a long-lasting atopic phenotype. Even though the outcome also depends on other factors (such as infection, functional state of the intestinal microflora, and exposure to environmental allergens at times critical to development), it seems that the immune system during the perinatal period is responsive to interventions that are no longer effective in adulthood. We have reviewed the literature accessible through Medline to identify recent advances in the prevention of allergic disease through interventions in the fetal-maternal relationship. Diet seems to have a significant impact on the immunological profile of the pregnant uterus, as well as on the postnatal development of allergic disease in the offspring, as suggested by the effects of probiotic bacteria and by manipulations of the dietary content of polyunsaturated fatty acids and antioxidants. This highlights the need for further studies, in order to define the best intervention methods, the most appropriate time interval and the individuals who will most likely benefit from them.

scholarly journals Hubungan Perilaku Perdagangan Investor Dengan Volume Perdagangan Di Bursa Efek Indonesia

2009 ◽  
Vol 2 (1) ◽  
Author(s):  
Ghazali Syamni
Keyword(s):  
Trading Volume ◽  
Stock Exchange ◽  
Time Interval ◽  
Time Intervals ◽  
Using Data ◽  
Changes Over Time ◽  
Relationship Of ◽  
The Relationship ◽  
Order Pattern ◽  
Over Time

This paper examines the relationship of behavior trading investor using data detailed transaction history-corporate edition demand and order history in Indonesia Stock Exchange during period of March, April and May 2005. Peculiarly, behavior placing of investor order at trading volume. The result of this paper indicates that trading volume order pattern to have pattern U shape. The pattern happened that investors have strong desires to places order at the opening and close of compared to in trading periods. While the largest orders are of market at the opening indicates that investor is more conservatively when opening, where many orders when opening has not happened transaction to match. In placing order both of investor does similar strategy. By definition, informed investors’ orders more large than uninformed investors. If comparison of order examined hence both investors behavior relatively changes over time. But, statistically shows there is not ratio significant. This implies behavior trading of informed investors and uninformed investors stable relative over time. The result from regression analysis indicates that informed investors to correlate at trading volume in all time intervals, but not all uninformed investors correlates in every time interval. This imply investor order inform is more can explain trading volume pattern compared to uninformed investor order in Indonesia Stock Exchange. Finally, result of regression also finds that order status match has greater role determines trading volume pattern intraday especially informed buy match and informed sale match. While amend, open and withdraw unable to have role to determine intraday trading volume pattern.

A Method for Controlling Arrival Time to Prevent Late Arrival by Manipulating Vehicle Timetable Information

2020 ◽  
Vol 1 (1) ◽  
pp. 1-17
Author(s):  
Kyosuke Futami ◽  
Tsutomu Terada ◽  
Masahiko Tsukamoto
Keyword(s):  
Public Transportation ◽  
Psychological Factors ◽  
Arrival Time ◽  
Time Interval ◽  
Prototype System ◽  
Time Intervals ◽  
Target Vehicle ◽  
Late Arrival ◽  
Departure Time ◽  
The Relationship

Although it is socially and ethically important not to be late for a specified arrival time, late arrivals sometimes happen to people using public transportation. Although many methods aim to smooth a user's movement by providing useful information, there are few approaches to prevent late arrivals due to psychological factors. In this research, to make a user's arrival time earlier and thus prevent late arrival, we propose a method that manipulates time allowance by presenting information based on a psychological and cognitive tendency. We apply this method to a vehicle timetable system for the purpose of preventing public transit users from arriving after a target vehicle's departure time. Our proposed timetable system manipulates the time intervals between a user's target vehicle and other vehicles by introducing fictional elements such as hidden vehicles and inserted fictional vehicles. This method uses the relationship between the time allowance and the departure time interval, and it can make a user desire and accept arriving at a station earlier. We implemented a prototype system and conducted four experiments. The evaluation results confirmed that our proposed method is effective for changing a user's time allowance and actual arrival time.

Abstract 2753: The Relationship Between Pulmonary Vein Antrum Scarring Following Atrial Fibrillation Ablation and Procedural Success: Does Pulmonary Vein Isolation Matter?

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Troy J Badger ◽  
Robert S Oakes ◽  
Akram Shabaan ◽  
Nazem W Akoum ◽  
Nathan M Segerson ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Pulmonary Vein ◽  
Pulmonary Veins ◽  
Posterior Wall ◽  
Kaplan Meier ◽  
Number Of Patients ◽  
Procedural Success ◽  
The Relationship ◽  
Af Recurrence

Background. A mechanism of atrial fibrillation (AF) recurrence following ablation may be incomplete pulmonary vein antrum (PVA) scarring that allows for conduction between the pulmonary veins (PV) and the left atrium (LA). We report the relationship between circumferential PV scarring detected by delayed enhancement MRI (DE-MRI) and AF recurrence following PVAI. Methods. Eighty-six patients presenting for PVAI underwent DE-MRI 3 months post ablation. Circumferential ablation with posterior wall debulking was performed in all patients. PV ostia were marked on 3D images generated from the MRI data and assessed by consensus of two independent reviewers for the extent of scarring. Complete PVA scarring was defined as a continuous ring of enhancement surrounding the PVA. For patients with incomplete scarring, the degree of scarring was estimated. Results. The figure shows two patients from the cohort, Patient 1 exhibits successful scarring of all PVA. Patient 2 shows scarring of 1 PVA. At three months post ablation, complete circumferential lesion was seen on 131/335 PVA (39.1%). Complete scarring of 4 PVA was seen in 9 patients (10.5%), scarring of 3 PVA in 11 patients (12.8%) and scarring of 2 PVA was seen in 17 patients (19.8). Twenty-nine patients (33.7%) exhibited complete scarring in 1 PVA while 20 patients (23.3%) exhibited scarring in 0 PVA. Kaplan Meier analysis (Figure [E] ), suggests that PVA isolation may be important for long-term procedural success. Conclusion: Complete pulmonary vein antrum scarring exists in a very limited number of patients, despite its apparent importance for long-term procedural success.

QRS complex characteristics and patient outcomes in out-of-hospital pulseless electrical activity cardiac arrest

2020 ◽  
Vol 38 (1) ◽  
pp. 53-58
Author(s):  
Jung Ho Kim ◽  
Hyun Wook Ryoo ◽  
Jong-yeon Kim ◽  
Jae Yun Ahn ◽  
Sungbae Moon ◽  
...  
Keyword(s):  
Cardiac Arrest ◽  
Electrical Activity ◽  
Hospital Discharge ◽  
Neurological Outcome ◽  
Prospective Observational Study ◽  
Pulseless Electrical Activity ◽  
Secondary Outcome ◽  
Qrs Complex ◽  
The Relationship ◽  
Hospital Cardiac Arrest

BackgroundPulseless electrical activity (PEA) is increasingly observed in out-of-hospital cardiac arrest (OHCA), but outcomes are still poor. We aimed to assess the relationship between QRS characteristics and outcomes of patients with OHCA with initial PEA (OHCA-P).MethodsThis prospective observational study included patients aged at least 18 years who developed OHCA-P between 1 January 2016 and 31 December 2018, and were enrolled in the Daegu Emergency Medical Services registry, South Korea. We performed multivariable logistic regression analyses to identify the associations between QRS characteristics and OHCA-P outcomes, in which QRS complexes were considered separately (model 1) and simultaneously (model 2). The primary outcome was survival to hospital discharge and the secondary outcome was a favourable neurological outcome.ResultsOf the 3659 patients with OHCA, 576 were enrolled (median age 73 years; 334 men). A higher QRS amplitude was associated with survival to hospital discharge and a favourable neurological outcome in model 1 (adjusted OR (aOR) 1.077 and 1.106, respectively; 95% CI 1.021 to 0.136 and 1.029 to 1.190, respectively) and model 2 (aOR 1.084 and 1.123, respectively; 95% CI 1.026 to 1.145 and 1.036 to 1.216, respectively). A QRS width of <120 ms was associated with survival to hospital discharge and a favourable neurological outcome in model 1 (aOR 3.371 and 4.634, respectively; 95% CI 1.633 to 6.960 and 1.562 to 13.144, respectively) and model 2 (aOR 3.213 and 5.103, respectively; 95% CI 1.568 to 6.584 and 1.682 to 15.482, respectively). Survival to hospital discharge and neurological outcome were not associated with QRS frequency.ConclusionOHCA-P outcomes were better when the initial QRS complex showed a higher amplitude or narrower width.

scholarly journals Atmospheric Temperature and CO2: Hen-or-Egg Causality?

Sci ◽  
2020 ◽  
Vol 2 (4) ◽  
pp. 77
Author(s):  
Demetris Koutsoyiannis ◽  
Zbigniew Kundzewicz
Keyword(s):  
Atmospheric Carbon Dioxide ◽  
Common Knowledge ◽  
Carbon Dioxide Concentration ◽  
Co2 Concentration ◽  
Atmospheric Temperature ◽  
Time Interval ◽  
Reverse Causality ◽  
Time Step ◽  
Relationship Of ◽  
The Relationship

It is common knowledge that increasing CO2 concentration plays a major role in enhancement of the greenhouse effect and contributes to global warming. The purpose of this study is to complement the conventional and established theory that increased CO2 concentration due to human emissions causes an increase of temperature, by considering the reverse causality. Since increased temperature causes an increase in CO2 concentration, the relationship of atmospheric CO2 and temperature may qualify as belonging to the category of “hen-or-egg” problems, where it is not always clear which of two interrelated events is the cause and which the effect. We examine the relationship of global temperature and atmospheric carbon dioxide concentration at the monthly time step, covering the time interval 1980–2019, in which reliable instrumental measurements are available. While both causality directions exist, the results of our study support the hypothesis that the dominant direction is T → CO2. Changes in CO2 follow changes in T by about six months on a monthly scale, or about one year on an annual scale. We attempt to interpret this mechanism by involving biochemical reactions, as at higher temperatures soil respiration, and hence CO2 emission, are increasing.

Initiation of each avian inspiration by a CO2 threshold mechanism

1979 ◽  
Vol 47 (1) ◽  
pp. 233-239 ◽  
Author(s):  
D. A. Miller ◽  
A. L. Kunz
Keyword(s):  
Threshold Model ◽  
Co2 Concentration ◽  
Threshold Level ◽  
Mean Value ◽  
Wave Form ◽  
Time Interval ◽  
Threshold Mechanism ◽  
The Mean ◽  
The Relationship ◽  
Respiratory Movements

The avian respiratory oscillator has been investigated in a unidirectionally ventilated chicken by changing the dynamic pattern of inflow CO2 concentration (FCO2). Stimulation with periodic FCO2 results in a one-to-one synchronization of the respiratory movements that we have called pacing (Respir. Physiol. 22: 167--177, 1974). A two-parameter CO2 threshold model is proposed to explain this behavior. The model states that when FCO2 reaches a threshold level (L), it initiates the beginning of inspiration a constant time interval (LB) later. According to this model, when a triangular FCO2 concentration is used to synchronize the breathing pattern, the time from the minimum of the wave form to the beginning of inspiration (C-B interval) is dependent on the mean value and the rate of rise of FCO2 as determined by period and amplitude of the triangle. Particularly interesting is the prediction that the direction of the relationship (increasing or decreasing) between FCO2 amplitude and the C-B interval is dependent on whether the mean value of FCO2 is above or below the threshold level. Experimental data obtained during amplitude changes support the above prediction.

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