Sinus node inability or conduction disorders of its surrounding atrial myocardium cause sinus node dysfunction (SND). This study aimed to characterize right atrium (RA) substrates and long-term atrial lead performance after pacemaker implantation in non-senile SND patients.
Methods
Eighteen SND patients (53.3?±?9.6 years) controlled by 18 age-matched supraventricular tachycardia patients were consecutively enrolled. The P-wave amplitude (PWA) and P-wave duration (PWD) were measured on surface electrocardiography. Electroanatomic mapping was conducted to assess the bipolar voltage, complex signals, volume, and activation time of RA. Pacemaker implantation was performed in SND patients after mapping.
Results
Compared with controls, SND patients showed significant PWA reduction (0.13?±?0.02 vs. 0.16?±?0.04 mV, p?=?0.017) and PWD prolongation (120.8?±?15.2 vs. 105.2?±?8.6 ms, p?=?0.001). The RA endocardial voltage was lower (1.56?±?0.78 vs. 2.57?±?0.55 mV, p?<?0.001) and activation time was longer (112.1?±?14.9 vs. 90.8?±?12.4 ms, p?<?0.001) in the study group. Atrial lead was anchored at the lower atrial septum in one patient and failed in another due to extensive atrial scarring. During a median follow-up of 86 (57–88) months, one patient lost atrial capturing, and overall atrial sensing was significantly decreased (2.44?±?1.16 vs. 1.87?±?1.01 mV, p?=?0.003).
Conclusions
Atrial involvement was proved and the process was progressive in non-senile SND patients, as demonstrated by diffused RA lower voltage, slower conduction, and the decrease of the atrial lead sensing.
This paper describes the development and validation of a liquid chromatography–mass spectrometric assay for propafenone and its application to a pharmacokinetic study of propafenone administered as a new propafenone hydrochloride sustained-release capsule (SR-test), as an instant-release tablet (IR-reference) and as the market leader sustained-release capsule (Rythmol, SR-reference) in male beagle dogs (n=8). In Study A comparing SR-test with IR-reference in a crossover design Tmax and t1/2 of propafenone for SR-test were significantly higher than those for IR-reference while Cmax and AUC were lower demonstrating the sustained release properties of the new formulation. In Study B comparing SR-test with SR-reference the observed Cmax and AUC of propafenone for SR-test (124.5±140.0 ng/mL and 612.0±699.2 ng·h/mL, respectively) were higher than for SR-reference (78.52±72.92 ng/mL and 423.6±431.6 ng·h/mL, respectively) although the differences were not significant. Overall, the new formulation has as good if not better sustained release characteristics to the market leader formulation.KEY WORDS: Propafenone, Pharmacokinetics, Sustained-release, Beagle dog, Plasma相似文献
In this work, a two-component modified AgBr–Br–g-C3N4 composite catalyst with outstanding photocatalytic H2O2 production ability is synthesized. XRD, UV-Vis, N2 adsorption, TEM, XPS, EPR and PL were used to characterize the obtained catalysts. The as-prepared AgBr–Br–g-C3N4 composite catalyst shows the highest H2O2 equilibrium concentration of 3.9 mmol L−1, which is 7.8 and 19.5 times higher than that of GCN and AgBr. A “two channel pathway” is proposed for this reaction system which causes the remarkably promoted H2O2 production ability. In addition, compared with another two-component modified catalyst, Ag–AgBr–g-C3N4, AgBr–Br–g-C3N4 composite catalyst displays the higher photocatalytic H2O2 production ability and stability.In this work, a two-component modified AgBr–Br–g-C3N4 composite catalyst with outstanding photocatalytic H2O2 production ability is synthesized.相似文献
In the present study, aged refuse (AR) was modified to be applied as an adsorbent to remove humic acid from water. The efficiency of humic acid removal by modified aged refuse (MAR) under different preparation conditions (calcination temperature, dose of aged refuse for calcination and holding time) was systematically investigated. Results showed that the optimum preparation conditions are calcination temperature = 700 °C, AR dose for calcination = 25 g, and holding time = 2.0 h. The characteristics of the modified aged refuse obtained under different calcination conditions were determined by Fourier transform infrared, X-ray diffraction and X-ray photoelectron spectroscopy analysis. In addition, the effects of modified aged refuse dose and initial solution pH on adsorption performance were studied. The removal of humic acid increased with higher doses of modified aged refuse, and weak alkaline (initial pH = 8.0) conditions were favorable for humic acid removal. A pseudo-second order model fitted the experimental data well. Moreover, the adsorption isotherms were well described by the Langmuir isotherm model, in which the monolayer surface loading was calculated to be approximately 37 mg g−1. During the adsorption process, the molecular weight, degree of condensation and aromaticity of humic acid were considerably decreased, according to 3D-EEM analysis. MAR as a new type of adsorbent thus provides a potential adsorption method for humic acid.In the present study, aged refuse (AR) was modified to be applied as an adsorbent to remove humic acid from water. 相似文献
Background: Current studies have confirmed that fetal congenital heart diseases (CHDs) are caused by various factors. However, the quantitative risk of CHD is not clear given the combined effects of multiple factors. Objective: This cross-sectional study aimed to detect associated factors of fetal CHD using a Bayesian network in a large sample and quantitatively analyze relative risk ratios (RRs). Methods: Pregnant women who underwent fetal echocardiography (N = 16,086 including 3,312 with CHD fetuses) were analyzed. Twenty-six maternal and fetal factors were obtained. A Bayesian network is constructed based on all variables through structural learning and parameter learning methods to find the environmental factors that directly and indirectly associated with outcome, and the probability of fetal CHD in the two groups is predicted through a junction tree reasoning algorithm, so as to obtain RR for fetal CHD under different exposure factor combinations. Taking into account the effect of gestational week on the accuracy of model prediction, we conducted sensitivity analysis on gestational week groups. Results: The single-factor analysis showed that the RRs for the numbers of births, spontaneous abortions, and parental smoking were 1.50, 1.38, and 1.11 (P < 0.001), respectively. The risk gradually increased with the synergistic effect of ranging from one to more environmental factors above. The risk was higher among subjects with five synergistic factors, including the number of births, upper respiratory tract infection during early pregnancy, anemia, and mental stress as well as a history of spontaneous abortions or parental smoking, than in those with less than 5 factors (RR = 2.62 or 2.28, P < 0.001). This result was consistent across the participants grouped by GWs. Conclusion: We identified six factors that were directly associated with fetal CHD. A higher number of these factors led to a higher risk of CHD. These findings suggest that it is important to strengthen healthcare and prenatal counseling for women with these factors. 相似文献