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Efficient and stable bifunctional oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) catalysts are urgently needed to unlock the full potential of zinc‐air batteries (ZABs). High‐valence oxides (HVOs) and high entropy oxides (HEOs) are suitable candidates for their optimal electronic structures and stability but suffer from demanding synthesis. Here, a low‐cost fluorine‐lodged high‐valent high‐entropy layered double hydroxide (HV‐HE‐LDH) (FeCoNi2F4(OH)4) is conveniently prepared through multi‐ions co‐precipitation, where F− are firmly embedded into the individual hydroxide layers. Spectroscopic detections and theoretical simulations reveal high valent metal cations are obtained in FeCoNi2F4(OH)4, which enlarge the energy band overlap between metal 3d and O 2p, enhancing the electronic conductivity and charge transfer, thus affording high intrinsic OER catalytic activity. More importantly, the strengthened metal‐oxygen (M−O) bonds and stable octahedral geometry (M−O(F)6) in FeCoNi2F4(OH)4 prevent structural reorganization, rendering long‐term catalytic stability. Furthermore, an efficient three‐phase reaction interface with fast oxygen transportation was constructed, significantly improving the ORR activity. ZABs assembled with FeCoNi2F4(OH)4@HCC (hydrophobic carbon cloth) cathodes deliver a top performance with high round‐trip energy efficiency (61.3 % at 10 mA cm−2) and long‐term stability (efficiency remains at 58.8 % after 1050 charge–discharge cycles). [ABSTRACT FROM AUTHOR]

Qaidam cattle are a typical Chinese native breed inhabiting northwest China. They bear the characteristics of high cold and roughage tolerance, low‐oxygen adaptability and good meat quality. To analyze the genetic diversity of Qaidam cattle, 60 samples were sequenced using whole‐genome resequencing technology, along with 192 published sets of whole‐genome sequencing data of Indian indicine cattle, Chinese indicine cattle, North Chinese cattle breeds, East Asian taurine cattle, Eurasian taurine cattle and European taurine cattle as controls. It was found that Qaidam cattle have rich genetic diversity in Bos taurus, but the degree of inbreeding is also high, which needs further protection. The phylogenetic analysis, principal component analysis and ancestral component analysis showed that Qaidam cattle mainly originated from East Asian taurine cattle. Qaidam cattle had a closer genetic relationship with the North Chinese cattle breeds and the least differentiation from Mongolian cattle. Annotating the selection signals obtained by composite likelihood ratio, nucleotide diversity analysis, integrated haplotype score, genetic differentiation index, genetic diversity ratio and cross‐population extended haplotype homozygosity methods, several genes associated with immunity, reproduction, meat, milk, growth and adaptation showed strong selection signals. In general, this study provides genetic evidence for understanding the germplasm characteristics of Qaidam cattle. At the same time, it lays a foundation for the scientific and reasonable protection and utilization of genetic resources of Chinese local cattle breeds, which has great theoretical and practical significance. [ABSTRACT FROM AUTHOR]

Organic additives with high‐reduction potentials are generally applied in aqueous electrolytes to stabilize the Zn anode, while compromise safety and environmental compatibility. Highly concentrated water‐in‐salt electrolytes have been proposed to realize the high reversibility of Zn plating/stripping; however, their high cost and viscosity hinder their practical applications. Therefore, exploring low‐concentration Zn salts, that can be used directly to stabilize Zn anodes, is of primary importance. Herein, we developed an asymmetric anion group, bi(difluoromethanesulfonyl)(trifluoromethanesulfonyl)imide (DFTFSI‐)‐based novel zinc salt, Zn(DFTFSI)2, to obtain a high ionic conductivity and a highly stable dendrite‐free Zn anode. Experimental tests and theoretical calculations verified that DFTFSI− in the Zn2+ solvation sheath and inner Helmholtz plane would be preferentially reduced to construct layer‐structured SEI films, inhibiting hydrogen evolution and side reactions. Consequently, the Zn|| ${||}$ Zn symmetric cell with 1M Zn(DFTFSI)2 aqueous electrolyte delivers an ultralong cycle life for >2500 h outperforming many other conventional Zn salt electrolytes. The Zn|| ${||}$ Br2 battery also exhibits a long lifespan over 1200 cycles at ~99.8 % Coulombic efficiency with a high capacity retention of 92.5 %. Furthermore, this outstanding performance translates well to a high‐areal‐capacity Zn|| ${||}$ Br2 battery (~5.6 mAh ⋅ cm‐2), cycling over 320 cycles with 95.3 % initial capacity retained. [ABSTRACT FROM AUTHOR]

Although rechargeable aqueous zinc batteries are cost effectiveness, intrinsicly safe, and high activity, they are also known for bringing rampant hydrogen evolution reaction and corrosion. While eutectic electrolytes can effectively eliminate these issues, its high viscosity severely reduces the mobility of Zn2+ ions and exhibits poor temperature adaptability. Here, we infuse acetamide molecules with Lewis base and hydrogen bond donors into a solvated shell of Zn[(H2O)6]2+ to create Zn(H2O)3(ace)(BF4)2. The viscosity of 1ace‐1H2O is 0.032 Pa s, significantly lower than that of 1ace‐0H2O (995.6 Pa s), which improves ionic conductivity (9.56 mS cm−1) and shows lower freezing point of −45 °C, as opposed to 1ace‐0H2O of 4.04 mS cm−1 and 12 °C, respectively. The acidity of 1ace‐1H2O is ≈2.8, higher than 0ace‐1H2O at ≈0.76, making side reactions less likely. Furthermore, benefiting from the ZnCO3/ZnF2‐rich organic/inorganic solid electrolyte interface, the Zn || Zn cells cycle more than 1300 hours at 1 mA cm−2, and the Zn || Cu operated over 1800 cycles with an average Coulomb efficiency of ≈99.8 %. The Zn || PANI cell cycled over 8500 cycles, with a specific capacity of 99.8 mAh g−1 at 5 A g−1 at room temperature, and operated at −40 °C with a capacity of 66.8 mAh g−1. [ABSTRACT FROM AUTHOR]

Though massive efforts have been devoted to exploring Br‐based batteries, the highly soluble Br2/Br3− species causing rigorous "shuttle effect", leads to severe self‐discharge and low Coulombic efficiency. Conventionally, quaternary ammonium salts such as methyl ethyl morpholinium bromide (MEMBr) and tetrapropylammonium bromide (TPABr) are used to fix Br2 and Br3−, but they occupy the mass and volume of battery without capacity contribution. Here, we report an all‐active solid interhalogen compound, IBr, as a cathode to address the above challenges, in which the oxidized Br0 is fixed by iodine (I), thoroughly eliminating cross‐diffusing Br2/Br3− species during the whole charging and discharging process. The Zn||IBr battery delivers remarkably high energy density of 385.8 Wh kg−1, which is higher than those of I2, MEMBr3, and TPABr3 cathodes. Our work provides new approaches to achieve active solid interhalogen chemistry for high‐energy electrochemical energy storage devices. [ABSTRACT FROM AUTHOR]

Alkaline aqueous batteries such as the Zn||Ni batteries have attracted substantial interests due to their merits of high energy density, high safety and low cost. However, the freeze of aqueous electrolyte and the poor cycling stability in alkaline condition have hindered their operation in subzero conditions. Herein, we construct a stable aqueous electrolyte with lowest freezing point down to −90 °C by adding dimethyl sulfoxide (DMSO) as alkaline tolerant antifreezing additive into 1 M KOH solution. Meanwhile, we find the DMSO can also retard Zn anode corrosion and prevent Zn dendrite formation in alkaline condition, which enables the Zn plating/stripping over 700 h cycle at 1 mA cm−2 and 0.5 mAh cm−2. The fabricated Zn||Ni battery can endure low working temperature even down to −60 °C and its dischage capacity retains 84.1 % at −40 °C, 60.6 % at −60 °C at 0.5 C. Meanwhile, it can maintain 600 cycles with a specific capacity retention of 86.5 % at −40 °C at 2 C. [ABSTRACT FROM AUTHOR]

Batteries usually deliver mass loading‐dependent electrochemical performance. Taking the selenium cathode as an example, the Se reaction kinetics, utilization, and cycling lifespan seriously deteriorate with increased Se mass loading. Here, an electrocatalytic Se reduction/oxidation reaction strategy to realize high‐Se‐loading Zn||Se batteries with fast kinetics and high Se utilization is proposed. Specifically, the synergetic effects of Cu and Co transition‐metal species inside the channel structure of the host can effectively immobilize and catalytically convert Sen during cycling, which thus facilitates Se utilization and 6‐electron (Se4+ ↔ Se2–) conversion kinetics. In particular, the Cu[Co(CN)6] host exhibits a remarkably low energy barrier (1.63 kJ mol–1) and low Tafel slope (95.23 mV dec–1) for the Se reduction, and the highest current response for Se oxidation. Accordingly, the Zn battery employing a Se‐in‐Cu[Co(CN)6] cathode delivers a capacity of 664.7 mAh g–1 at 0.2 A g–1, an excellent rate capability with 430.6 mAh g–1 achieved even at 10 A g–1, and long‐cyclic life over 6000 cycles with 90.6% capacity retention. Furthermore, an A‐h‐level (≈1350 mAh) Zn||Se pouch‐type battery with high Se loading (≈12.3 mg(Se) cm–2) shows a high Se utilization of 83.3% and outstanding cyclic stability with 89.4% initial capacity retained after 400 cycles at exceeding 98% Coulombic efficiency. [ABSTRACT FROM AUTHOR]

Inv22-1 present in 45% of inhibitor-positive HA patients, but also present in 33% of inhibitor-negative HA patients (see Figure 1A), so Inv22-1 is not a good genetic marker for inhibitor production. Low FVIII activity is also found in other diseases, such as von Willebrand disease (vWD) and acquired haemophilia A (AHA), so diagnosis of HA should be more cautious. Dear Editor, Haemophilia A (HA) is a coagulation disorder with deficiency/dysfunction of coagulation factor VIII (FVIII) and is one of the most common recessive X-linked hereditary diseases. [Extracted from the article]

Proposed are Prussian blue analogue hosts with ordered and continuous channels, and electrocatalytic functionality with open Co and Fe species, which facilitate maximum I2 utilization efficiency and direct I2 to I− conversion kinetics of the I2 reduction reaction, and free up 1/3 I− from I3−. Co[Co1/4Fe3/4(CN)6] exhibits a low energy barrier (0.47 kJ mol−1) and low Tafel slope (76.74 mV dec−1). Accordingly, the Co[Co1/4Fe3/4(CN)6]/I2//Zn battery delivers a capacity of 236.8 mAh g−1 at 0.1 A g−1 and a rate performance with 151.4 mAh g−1 achieved even at 20 A g−1. The battery delivers both high energy density and high‐power density of 305.5 Wh kg−1 and 109.1 kW kg−1, higher than I2//Zn batteries reported to date. Furthermore, solid‐state flexible batteries were constructed. A 100 mAh high capacity solid‐state I2//Zn battery is demonstrated with excellent cycling performance of 81.2 % capacity retained after 400 cycles. [ABSTRACT FROM AUTHOR]

Zn batteries are usually considered as safe aqueous systems that are promising for flexible batteries. On the other hand, any liquids, including water, being encapsulated in a deformable battery may result in problems. Developing completely liquid‐free all‐solid‐state Zn batteries needs high‐quality solid‐state electrolytes (SSEs). Herein, we demonstrate in situ polymerized amorphous solid poly(1,3‐dioxolane) electrolytes, which show high Zn ion conductivity of 19.6 mS cm−1 at room temperature, low interfacial impedance, highly reversible Zn plating/stripping over 1800 h cycles, uniform and dendrite‐free Zn deposition, and non‐dry properties. The in‐plane interdigital‐structure device with the electrolyte completely exposed to the open atmosphere can be operated stably for over 30 days almost without weight loss or electrochemical performance decay. Furthermore, the sandwich‐structure device can normally operate over 40 min under exposure to fire. Meanwhile, the interfacial impedance and the capacity using in situ‐formed solid polymer electrolytes (SPEs) remain almost unchanged after various bending tests, a key criterion for flexible/wearable devices. Our study demonstrates an approach for SSEs that fulfill the requirement of no liquid and mechanical robustness for practical solid‐state Zn batteries. [ABSTRACT FROM AUTHOR]

Zn‐air batteries (ZABs) offer promising commercialization perspectives for stretchable and wearable electronic devices as they are environment‐friendly and have high theoretical energy density. However, current devices suffer from limited energy efficiency and durability because of the sluggish oxygen reduction and evolution reactions kinetics in the air cathode as well as degenerative stretchability of solid‐state electrolytes under highly alkaline conditions. Herein, excellent bifunctional catalytic activity and cycling stability is achieved by using a newly developed Co–N–C nanomaterial with a uniform virus‐like structure, prepared via a facile carbonization of a prussian blue analogue (PBA). Furthermore, a solid‐state dual‐network sodium polyacrylate and cellulose (PANa‐cellulose) based hydrogel electrolyte is synthesized with good alkaline‐tolerant stretchability. A solid‐state fiber‐shaped ZAB fabricated using this hydrogel electrolyte, the virus‐like Co–N–Cs air cathode, and a zinc spring anode display excellent stretchability of up to 500% strain without damage, and outstanding electrochemical performance with 128 mW cm−2 peak power density and good cycling stability for >600 cycles at 2 mA. The facile synthesis strategy demonstrated here opens up a new avenue for developing highly active PBA‐derived catalyst and shows, for the first time, that virus‐like structure can be favorable for electrochemical performance. [ABSTRACT FROM AUTHOR]

Contrasting Y-chromosomal lineage distributions in Chinese domestic yak Yak ( I Bos grunniens i ) is a valuable bovine species that lives in the central Asian highlands with more than 15 million animals living in China.[1] Previous Y-SNP markers analyses revealed two yak paternal lineages, Y1 and Y2, in the Gaoyuan, Datong, Huanhu and Tianzhu breeds.[[2]] Here, we present a comprehensive survey of the lineage distributions in the 12 recognized Chinese domestic yak breeds. The differential distributions of the yak lineages Y1 and Y2 reveal a clear phylogeographical structure among Chinese domestic yak breeds, in clear contrast to nuclear microsatellite and mitochondrial analyses on domestic yak.[[4]]. [Extracted from the article]

Herein, a two‐species redox reaction of Co(II)/Co(III) and Fe(II)/Fe(III) incorporated in cobalt hexacyanoferrate (CoFe(CN)6) is proposed as a breakthrough to achieve jointly high‐capacity and high‐voltage aqueous Zn‐ion battery. The Zn/CoFe(CN)6 battery provides a highly operational voltage plateau of 1.75 V (vs metallic Zn) and a high capacity of 173.4 mAh g−1 at current density of 0.3 A g−1, taking advantage of the two‐species redox reaction of Co(II)/Co(III) and Fe(II)/Fe(III) couples. Even under extremely fast charge/discharge rate of 6 A g−1, the battery delivers a sufficiently high discharge capacity of 109.5 mAh g−1 with its 3D opened structure framework. This is the highest capacity delivered among all the batteries using Prussian blue analogs (PBAs) cathode up to now. Furthermore, Zn/CoFe(CN)6 battery achieves an excellent cycling performance of 2200 cycles without any capacity decay at coulombic efficiency of nearly 100%. One further step, a sol–gel transition strategy for hydrogel electrolyte is developed to construct high‐performance flexible cable‐type battery. With the strategy, the active materials can adequately contact with electrolyte, resulting in improved electrochemical performance (≈18.73% capacity increase) and mechanical robustness of the solid‐state device. It is believed that this study optimizes electrodes by incorporating multi redox reaction species for high‐voltage and high‐capacity batteries. [ABSTRACT FROM AUTHOR]

Stretchable devices need elastic hydrogel electrolyte as an essential component, while most hydrogels will lose their stretchability after being incorporated with strong alkaline solution. This is why highly stretchable zinc–air batteries have never been reported so far. Herein, super‐stretchable, flat‐ (800% stretchable) and fiber‐shaped (500% stretchable) zinc–air batteries are first developed by designing an alkaline‐tolerant dual‐network hydrogel electrolyte. In the dual‐network hydrogel electrolyte, sodium polyacrylate (PANa) chains contribute to the formation of soft domains and the carboxyl groups neutralized by hydroxyls as well as cellulose as potassium hydroxide stabilizer are responsible for vastly enhanced alkaline tolerance. The obtained super‐stretchable, flat zinc–air battery exhibits a high power density of 108.6 mW⋅cm−2, increasing to 210.5 mW⋅cm−2 upon being 800% stretched. Similar phenomena are observed for the 500% stretchable fiber‐shaped batteries. The devices can maintain stable power output even after being heavily deformed benefiting from the highly soft, alkaline‐tolerant hydrogel electrolyte developed. A bendable battery‐display system and water proof weavable fiber zinc–air battery are also demonstrated. This work will facilitate the progress of using zinc–air battery powering flexible electronics and smart clothes. Moreover, the developed alkaline‐tolerant super‐stretchable electrolyte can also be applied for many other alkaline electrolyte‐based energy storage/conversion devices. An alkaline‐tolerant, dual‐network hydrogel electrolyte‐based sodium polyacrylate and cellulose is developed. The hydrogel infiltrated by 6 m KOH solution as electrolyte still shows over 1000% stretchability, together with a 0.28 S∙cm−1 ion conductivity. Super‐stretchable, flat‐ (800% stretchable) and fiber‐shaped (500% stretchable) zinc–air batteries with high electrochemical performance and mechanical flexibility are developed based on the hydrogel electrolyte. [ABSTRACT FROM AUTHOR]

Aims: Right ventricular pacing (RVP) dependence could impair left ventricular ejection fraction (LVEF). This study aimed to illuminate the relationship between RVP proportion and LVEF, as well as disclosing independent predictors of RVP dependence. Methods and results: Patients indicated for permanent pacemaker implantation were included (2016–2020). The ventricular pacing lead was placed in right ventricular apex or septum. Pacing mode programming followed universal standard. Electrocardiographic, echocardiographic, and serological parameters were collected. RVP dependence was defined according to its influence on LVEF. This study was of case–control design. Included patients were matched by potentially confounding factors through propensity score matching. A total of 1183 patients were included, and the mean duration of follow‐up was 24 months. Percentage of RVP < 80% hardly influenced LVEF; however, LVEF tended to decrease with higher RVP proportion. High degree/complete atrioventricular block (AVB) [odds ratio (OR) = 5.71, 95% confidence interval (CI): 3.66–8.85], atrial fibrillation (AF) (OR = 2.04, 95% CI: 1.47–2.82), percutaneous coronary intervention (PCI) (OR = 2.89, 95% CI: 1.24–6.76), maximum heart rate (HRmax) < 110 b.p.m. (OR = 2.74, 95% CI: 1.58–4.76), QRS duration > 120 ms (OR = 2.46, 95% CI: 1.42–4.27), QTc interval > 470 ms (OR = 2.01, 95% CI: 1.33–3.05), and pulmonary artery systolic pressure (PASP) > 40 mmHg (OR = 1.93, 95% CI: 1.46–2.56) were proved to predict RVP dependence. Conclusions: High RVP percentage (>80%) indicating RVP dependence significantly correlates with poor prognosis of cardiac function. High degree/complete AVB, AF, ischaemic aetiology, PCI history, HRmax < 110 b.p.m., QRS duration > 120 ms, QTc interval > 470 ms, and PASP > 40 mmHg were verified as independent risk factors of RVP dependence. [ABSTRACT FROM AUTHOR]

Aims: We aimed to characterize ethnic differences in prevalence, clinical correlates, and outcomes of atrial fibrillation (AF) in heart failure (HF) with preserved and reduced ejection fraction (HFpEF and HFrEF) across Asia. Methods and results: Among 5504 patients with HF prospectively recruited across 11 Asian regions using identical protocols in the Asian Sudden Cardiac Death in Heart Failure study (mean age 61 ± 13 years, 27% women, 83% HFrEF), 1383 (25%) had AF defined as a history of AF and/or AF/flutter on baseline electrocardiogram. Clinical correlates of AF were similar across ethnicities and included older age, prior stroke, higher NT‐proBNP, and larger left atria. Diabetes was associated with lower odds of AF in HFrEF [adjusted odds ratio (AOR) 0.79, 95% CI 0.66–0.95] and HFpEF (AOR 0.58, 95% CI 0.39–0.84) regardless of ethnicity. Compared with Chinese ethnicity, Japanese/Koreans had higher odds of AF in HFrEF (AOR 1.76, 95% CI 1.40–2.21), while Indians had lower odds in HFrEF (AOR 0.18, 95% CI 0.13–0.24) and HFpEF (AOR 0.28, 95% CI 0.16–0.49) even after adjusting for clinical covariates. Interaction between ethnicity and region was observed among Indians, with Southeast Asian Indians having higher odds of AF (AOR 3.01, 95% CI 1.60–5.67) compared with South Asian Indians. AF was associated with poorer quality of life and increased risk of 1 year all‐cause mortality or HF hospitalisation (adjusted hazard ratio 1.39, 95% CI 1.18–1.63) regardless of ethnicity. Conclusions: Among patients with HF across Asia, clinical correlates and adverse outcomes associated with AF are similar across ethnicities; however, there are striking ethnic variations in the prevalence of AF that are not accounted for by known risk factors. [ABSTRACT FROM AUTHOR]

Abstract: Background: Abnormal cardiac repolarization is closely associated with ventricular tachycardia/ventricular fibrillation (VT/VF). Myocardial ischemia and infarction aggravate cardiac repolarization dispersion, and VT/VF could be lethal in the early stage of ST‐segment elevation myocardial infarction (STEMI). Unfortunately, VT/VF cannot be effectively predicted in current clinical practice. The present study aimed to assess electrocardiographic parameters of the sinus rhythmic complex in relation to cardiac repolarization, e.g., QT interval and T‐peak to T‐end interval (TpTe), to independently predict VT/VF in acute STEMI. Additionally, we hypothesized that QT and TpTe of PVC would be also valuable to predict VT/VF in STEMI. Methods and results: A total of 198 cases diagnosed as STEMI with PVC on admission by electrography were included. During hospitalization, VT/VF values were recorded. Logistic analysis was performed between patients with and without VT/VF to validate independent electrocardiographic predictors. QTcPVC interval > 520 ms (OR = 3.2; P = 0.027), TpTe interval > 100 ms (OR = 3.1; P = 0.04), TpTePVC > 101 ms (OR = 3.6; P = 0.029), TpTe/QT > 0.258 (OR = 5.7; P = 0.003), and TpTe/QTPVC > 0.253 (OR = 3; P = 0.048). However, QRS duration, QTc interval, coupling interval, and QRSPVC duration did not predict VT/VF. Besides, QRSPVC duration >140 ms (OR = 2.6; P = 0.001) independently predicted LVEF decrease after 1 year or more. Conclusions: QTcPVC interval, TpTe interval, TpTePVC interval, TpTe/QT ratio, and TpTe/QTPVC ratio are risk factors for ECG independent from other confounding factors in predicting VT/VF in the acute phase of STEMI. In addition, PVC characteristics as risk factors for VT/VF in acute phase and LVEF decrease in chronic phase were firstly reported. [ABSTRACT FROM AUTHOR]

CRT and Myocardial Fibrosis Introduction Though cardiac resynchronization therapy (CRT) has now proved to be effective on cardiac reverse remodeling, data on the underlying molecular changes are limited. The present study aims to investigate the expression of cytokines concerning myocardial fibrosis in dyssynchronous heart failure (HF) and the potential benefits of CRT. Methods and Results Left bundle branch ablation and rapid pacing was performed to induce a canine model of asynchronous HF. Animals were randomly divided into sham group, HF control group, and CRT group. Echocardiographic data including septum-to-posterior wall motion delay (SPWMD) and standard deviation of the time to peak systolic velocity (Ts-SD) were collected. Histologic samples from lateral left ventricular (LV) and right ventricular (RV) free wall were analyzed and compared among different groups. Serum concentrations of NT-proBNP, TGF-β1, and osteopontin (OPN) were measured using enzyme-linked immunosorbent assay (ELISA). Protein and mRNA expressions of TGF-β1/Smad and OPN from myocardial tissues were also detected and compared. CRT improved cardiac function and corrected intraventricular dyssynchrony with increased LV ejection fraction (LVEF) and decreased SPWMD and Ts-SD (P < 0.05). Histological analysis showed that CRT restored cardiomyocyte diameter (from 4.50 to 6.08 μm) and collagen volume fraction (from 19.33% to 11.21%) of LV (P < 0.01), but had little effect on RV. Serum TGF-β1 and OPN level were also reversed toward normal level after CRT (P < 0.05). Compared with sham group, a significantly higher protein and mRNA expressions of TGF-β1/Smad and OPN were observed in HF control group, which were significantly downregulated in CRT group (P < 0.01). Conclusion By means of coordinating LV dyssynchrony, cellular and molecular reverse remodeling relevant to fibrosis inhibition could also be invoked by CRT. [ABSTRACT FROM AUTHOR]

Sudden cardiac death (SCD) is a major cause of morbidity and mortality in patients with coronary artery diseases and myocardial infarction (MI). There is a circadian variation of the frequency of SCD. Beta-blocker therapy significantly reduces the incidence of SCD after MI. These clinical observations suggest a close association between ventricular arrhythmia and sympathetic activity in patients with MI. Following injury, peripheral nerves undergo Wallerian degeneration, which may be followed by neurilemma cell proliferation and axonal regeneration (nerve sprouting), resulting in sympathetic hyperinnervation. It is possible that the increased innervation after myocardial injury may result in increased sympathetic nerve density, which in turn increases the propensity for cardiac arrhythmia. While this Nerve Sprouting Hypothesis seemed to be intuitive, there was no experimental proof of a causal link between sympathetic nerve sprouting and arrhythmogenesis. We therefore performed several studies to determine the relationship between nerve sprouting and cardiac arrhythmia. We also performed direct sympathetic nerve recording in an animal model of SCD. We found that cardiac sympathetic nerves are highly plastic. In addition to MI and rapid pacing, nerve sprouting and heterogeneous sympathetic hyperinnervation may also be induced by radiofrequency ablation, hypercholesterolemia, and stem cells transplantation. The coexistence of denervated and hyperinnervated area in the diseased myocardium could result in increased electrophysiological heterogeneity during sympathetic activation, leading to ventricular arrhythmia and SCD. [ABSTRACT FROM AUTHOR]