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Objective: To determine the feasibility of using temporary permanent pacemaker (TPPM) in patients with high-degree atrioventricular block (AVB) after transcatheter aortic valve replacement (TAVR) as bridging strategy to reduce avoidable permanent pacemaker implantation. Methods: This is a prospective observational study. Consecutive patients undergoing TAVR at Beijing Anzhen Hospital and the First Affiliated Hospital of Zhengzhou University from August 2021 to February 2022 were screened. Patients with high-degree AVB and TPPM were included. Patients were followed up for 4 weeks with pacemaker interrogation at every week. The endpoint was the success rate of TPPM removal and free from permanent pacemaker at 1 month after TPPM. The criteria of removing TPPM was no indication of permanent pacing and no pacing signal in 12 lead electrocardiogram (EGG) and 24 hours dynamic EGG, meanwhile the last pacemaker interrogation indicated that ventricular pacing rate was 0. Routinely follow-up ECG was extended to 6 months after removal of TPPM. Results: Ten patients met the inclusion criteria for TPPM, aged (77.0±11.1) years, wirh 7 females. There were 7 patients with third-degree AVB, 1 patient with second-degree AVB, 2 patients with first degree AVB with PR interval>240 ms and LBBB with QRS duration>150 ms. TPPM were applied on the 10 patients for (35±7) days. Among 8 patients with high-degree AVB, 3 recovered to sinus rhythm, and 3 recovered to sinus rhythm with bundle branch block. The other 2 patients with persistent third-degree AVB received permanent pacemaker implantation. For the 2 patients with first-degree AVB and LBBB, PR interval shortened to within 200 ms. TPPM was successfully removed in 8 patients (8/10) at 1 month without permanent pacemaker implantation, of which 2 patients recovered within 24 hours after TAVR and 6 patients recovered 24 hours later after TAVR. No aggravation of conduction block or permanent pacemaker indication were observed in 8 patients during follow-up at 6 months. No procedure-related adverse events occurred in all patients. Conclusion: TPPM is reliable and safe to provide certain buffer time to distinguish whether a permanent pacemaker is necessary in patients with high-degree conduction block after TAVR.
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Bloqueo Atrioventricular , Marcapaso Artificial , Reemplazo de la Válvula Aórtica Transcatéter , Femenino , Humanos , Bloqueo Atrioventricular/terapia , Estudios de Factibilidad , Bloqueo de RamaRESUMEN
Up to now, a nation-wide scale study of surface ozone (O3) concentrations in China was limited due to scarce observation. Thanks to the establishment of national air quality monitoring network in 2013, surface O3 data from 1402 stations during 2014-2017 were collected to investigate O3 seasonality. Our analysis reveals that the variations of monthly O3 averaged from daily mean concentration during a year show different temporal profiles depending on latitude. A unimodal structure (UMS) is generally found for latitudes over 35°N, whereas a bimodal structure (BMS) is in most of the cases identified south of 35°N. The peak of UMS is found in the period of May to July, whereas the first and second peaks of BMS are found from April to June, and from July to October, respectively. In addition, the seasonality of O3 presents a strong dependence on pseudo-equivalent potential temperature and monsoonal clouds. The onset and retreat of warm and wet air are correlated to the summer minimum in BMS cases and to the sharp decrease of UMS in July. As far as the relationships between O3 and carbon monoxide are concerned, the effects of clean maritime air masses on the summer trough of O3 are not significant for inland sites. Overall, summer monsoon bringing warm and moist air and subsequent clouds leads to the suppression of photochemical production, thereby contributing directly to the geographical distribution of O3 seasonality.
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To evaluate the impact of emission control measures on the air quality in the Pearl River Delta (PRD) region of South China, statistic data including atmospheric observations, emissions and energy consumptions during 2006-2014 were analyzed, and a Weather Research and Forecasting - Community Multi-scale Air Quality (WRF-CMAQ) model was used for various scenario simulations. Although energy consumption doubled from 2004 to 2014 and vehicle number significantly increased from 2006 to 2014, ambient SO2, NO2 and PM10 were reduced by 66%, 20% and 24%, respectively, mainly due to emissions control efforts. In contrast, O3 increased by 19%. Model simulations of three emission control scenarios, including a baseline (a case in 2010), a CAP (a case in 2020 assuming control strength followed past control tendency) and a REF (a case in 2020 referring to the strict control measures based on recent policy/plans) were conducted to investigate the variations of air pollutants to the changes in NOx, VOCs and NH3 emissions. Although the area mean concentrations of NOx, nitrate and PM2.5 decreased under both NOx CAP (reduced by 1.8%, 0.7% and 0.2%, respectively) and NOx REF (reduced by 7.2%, 1.8% and 0.3%, respectively), a rising of PM2.5 was found in certain areas as reducing NOx emissions elevated the atmospheric oxidizability. Furthermore, scenarios with NH3 emission reductions showed that nitrate was sensitive to NH3 emissions, with decreasing percentages of 0-10.6% and 0-48% under CAP and REF, respectively. Controlling emissions of VOCs reduced PM2.5 in the southwestern PRD where severe photochemical pollution frequently occurred. It was also found that O3 formation in PRD was generally VOCs-limited while turned to be NOx-limited in the afternoon (13:00-17:00), suggesting that cutting VOCs emissions would reduce the overall O3 concentrations while mitigating NOx emissions in the afternoon could reduce the peak O3 levels.
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Contaminantes Atmosféricos/análisis , Contaminación del Aire/prevención & control , Monitoreo del Ambiente , Ozono/análisis , Material Particulado/análisis , Emisiones de Vehículos/prevención & control , Amoníaco/análisis , China , Óxidos de Nitrógeno/análisis , Estaciones del Año , Emisiones de Vehículos/análisis , Compuestos Orgánicos Volátiles/análisisRESUMEN
In this study, an experimental rat ligated heart model was used to observe the effect of treatment with carvedilol, metoprolol and metoprolol plus a highly selective alpha(1)-adrenergic blocking agent, bunazosin, after acute myocardial infarction (MI). Compared with an untreated MI group, all drug-treated groups demonstrated attenuation of inflammatory mediators, activation of nuclear factor-kappaB (NF-kappaB), and increased levels of mRNA and active protein for the collagenases matrix metallopeptidase (MMP)-8 and MMP-13 in the non-infarct zone of the ventricle, as well as inhibition of the increase of left ventricular end-diastolic pressure. Supplementation of metoprolol with bunazosin did not add greatly to the effects of metoprolol alone. Of the three drug treatments, carvedilol showed a uniquely potent antioxidant activity that may strengthen its capacity to inhibit oxidative stress, the release of inflammatory mediators and activation of NF-kappaB. This study may help provide a mechanistic explanation for the greater benefits shown by carvedilol compared with metoprolol in treating heart failure.
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Carbazoles/farmacología , Corazón/efectos de los fármacos , Infarto del Miocardio/tratamiento farmacológico , Estrés Oxidativo , Propanolaminas/farmacología , Vasodilatadores/farmacología , Enfermedad Aguda , Animales , Antioxidantes , Western Blotting , Carvedilol , Combinación de Medicamentos , Ensayo de Cambio de Movilidad Electroforética , Femenino , Mediadores de Inflamación/metabolismo , Ligadura , Metaloproteinasa 13 de la Matriz/genética , Metaloproteinasa 13 de la Matriz/metabolismo , Metaloproteinasa 8 de la Matriz/genética , Metaloproteinasa 8 de la Matriz/metabolismo , Metoprolol/farmacología , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , FN-kappa B/genética , FN-kappa B/metabolismo , Quinazolinas/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Inhibidor Tisular de Metaloproteinasa-1/genética , Inhibidor Tisular de Metaloproteinasa-1/metabolismoRESUMEN
Most lakes in the eastern part of China are eutrophic and non-point pollution accounts for more than half of the nutrient load to the lakes and reservoirs. Some efforts have been made to reduce the non-point source pollution in the catchments of sensitive water bodies. Technologies for the control of non-point pollution in Chinese rural areas are multipond systems, biogas fermentation, hilly area ecological agriculture, constructed wetlands, ecotone engineering and others. They are effective in the removal of nutrients from the runoff water or reduction of waste, and they are used with multi-purposes. To control non-point pollution, the cooperation with farmers and other residents in the countryside is the key to success, and the program has to consider their benefits. There are still many difficulties with its control, and more efforts are needed to develop suitable technologies and environmental education.