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Background: Cardioneuroablation is an emerging therapy for refractory vasovagal syncope (VVS), but the standard enrollment criterion is undetermined. Mainstream studies empirically enroll patients with cardioinhibitory and mixed types of VVS on the basis of the head-up tilt (HUT). However, a variety of studies have shown that the results of HUT exhibit unpleasant reproducibility.Objective: We aimed to investigate the prognostic value of baseline deceleration capacity in patients with refractory VVS after cardioneuroablation.Methods: This study enrolled 123 patients (mean age 42.2±17.7 years; 54 males [43.9%]) with the diagnosis of VVS, of whom 16 patients had a negative result of HUT (13.0%), 8 (6.5%) had vasodepressive VVS, 32 (26.0%) cardioinhibitory VVS, and 67 (54.5%) mixed VVS. All patients underwent cardioneuroablation that was performed in the left atrium.Results: After a mean follow-up of 4.0±1.1 years, 33 patients experienced syncope/presyncope events (26.8%). Patients with recurrent syncope/presyncope have a lower baseline deceleration capacity level than do those without (8.9±3.2 ms vs 11.3±3.7 ms; P < .001). Each 1-ms increase in deceleration capacity had a 34% (95% confidence interval [CI] 12%-50%) reduced risk of syncope/presyncope recurrence after cardioneuroablation. Nighttime deceleration capacity had the highest discrimination value (area under the curve 0.757; 95% confidence interval 0.657-0.858). At a high-risk threshold of 51% (nighttime deceleration capacity at a cutoff of 9.9 ms), the nighttime deceleration capacity enrollment strategy additionally benefited 18 per 100 patients after cardioneuroablation without syncope/presyncope recurrence as compared with the HUT strategy in decision curve analyses.Conclusion: Baseline nighttime deceleration capacity ≥ 10 ms may act as an indication for cardioneuroablation in patients with refractory VVS. [ABSTRACT FROM AUTHOR]

Autoimmune myocarditis, with increasing incidence and limited therapeutic strategies, is in urgent need to explore its underlying mechanisms and effective drugs. Pyroptosis is a programmed cell death that may contribute to the pathogenesis of myocarditis. Nonetheless, no direct evidence validated the role of pyroptosis in autoimmune myocarditis. Lupeol (Lup), a pentacyclic triterpene, possesses various biological activities such as antidiabetic properties. However, the effects of Lup on autoimmune myocarditis and pyroptosis remain unelucidated. This study aimed to reveal the role of pyroptosis in autoimmune myocarditis and explore the protective effects of Lup, and its engaged mechanisms. The experimental autoimmune myocarditis (EAM) mouse model was established by immunization with a fragment of cardiac myosin in Balb/c mice. Lup and MCC950 were administered after EAM induction. The protective effects were assessed by inflammation score, cardiac injury, chronic fibrosis, and cardiac function. Mechanistically, the effects of Lup on the M1 polarization and pyroptosis of macrophages were evaluated. Transcriptome sequencing and molecular docking were subsequently employed, and the underlying mechanisms of Lup were further explored in vitro with small interfering RNA and adenovirus. Administration of Lup and MCC950 alleviated EAM progression. Western blotting and immunofluorescence staining identified macrophages as the primary cells undergoing pyroptosis. Lup inhibited the expression of pyroptosis-associated proteins in macrophages during EAM in a dose-dependent manner. Furthermore, Lup suppressed pyroptosis in both bone marrow-derived macrophages (BMDMs) and THP-1-derived macrophages in vitro. In addition, Lup inhibited the M1 polarization of macrophages both in vivo and in vitro. Mechanistically, the protective effects of Lup were demonstrated via the suppression of the nuclear factor-κΒ (NF-κB) signaling pathway. Transcriptome sequencing and molecular docking revealed the potential involvement of peroxisome proliferator-associated receptor α (PPARα). Subsequently, we demonstrated that Lup activated PPARα to reduce the expression level of LACC1, thereby inhibiting the NF-κB pathway and pyroptosis. Our findings indicated the crucial role of macrophage pyroptosis in the pathogenesis of EAM. Lup ameliorated EAM by inhibiting the M1 polarization and pyroptosis of macrophages through the PPARα/LACC1/NF-κB signaling pathway. Thus, our results provided a novel therapeutic target and agent for myocarditis. [Display omitted] [ABSTRACT FROM AUTHOR]

Stress hyperglycemia has been associated with poor prognosis in patients admitted to the cardiac intensive care unit (ICU). Recently, the stress hyperglycemia ratio (SHR) has been proposed to reflect true acute hyperglycemic. This study aimed to investigate the relationship between SHR and prognosis of patients in the cardiac ICU. A retrospective analysis was conducted on a cohort of 5,564 patients admitted to the cardiac ICU. The participants were divided into seven groups based on their SHR levels. SHR was calculated as admission blood glucose/[(28.7 × HbA1c %) - 46.7]. The primary outcomes of this study were 28-day all-cause mortality. During the follow-up period, 349 (6.3%) patients succumbed within 28 days. A U-shaped correlation between SHR and mortality persisted, even after adjusting for other confounding variables, with a discernible inflection point at 0.95. When SHR surpassed 0.95, each standard deviation (SD) increase corresponded to a 1.41-fold elevation in the risk of mortality (odds ratio [OR]: 1.41, 95% CI: 1.25 to 1.59). In contrast, when SHR fell below 0.95, each SD increment correlated with a significantly reduced risk of mortality (OR: 0.56, 95% CI: 0.34 to 0.91). There was a U-shaped association between SHR and short -term mortality in patients in the cardiac ICU. The inflection point of SHR for poor prognosis was identified at an SHR value of 0.95. • Stress hyperglycemia ratio predicts prognosis in cardiac ICU patients with a U-shaped association for 28-day mortality. • Mild-to-moderate stress hyperglycemia ratio has a protective effect, while deviations increase mortality risk. • A stress hyperglycemia ratio of 0.95 identifies the poor prognosis threshold in this patient population. [ABSTRACT FROM AUTHOR]

Background: Catheter ablation of ganglionated plexus (GP) as cardioneuroablation in the left atrium (LA) has been used to treat vasovagal syncope (VVS).Objective: The purpose of this study was to assess the effects of ablation of GPs on heart rate and to observe the acute, short-term, and long-term effects after cardioneuroablation.Methods: A total of 115 consecutive patients with VVS who underwent cardioneuroablation were enrolled. GPs of the LA were identified by high-frequency stimulation and/or anatomic landmarks being targeted by radiofrequency catheter ablation.Results: During ablation of right anterior ganglionated plexus (RAGP), heart rate increased from 61.3 ± 12.2 bpm to 82.4 ± 14.7 bpm (P <.001), whereas during ablation of other GPs only vagal responses were observed. During follow-up of 21.4 ± 13.1 months (median 18 months), 106 participants (92.2%) had no recurrence of syncope or presyncope. Holter data showed that minimal heart rate significantly increased at all follow-up time points (all P<.05), and mean heart rate remained higher than baseline 12 months after ablation (P = .001).Conclusion: Cardioneuroablation via GP ablation in the LA effectively inhibited the recurrence of VVS. Ablation of RAGP could increase heart rate immediately and for the long term. This unique phenomenon may provide a new potential approach for treatment of neural reflex syncope or bradyarrhythmias. [ABSTRACT FROM AUTHOR]

As a novel drilling fluid, Fuzzy-ball Drilling Fluid has been successfully utilized to control the collapse and lost circulation in approximately 1000 coal bed methane wells by now. However, in terms of current research, its mechanism of controlling wellbore instability has not yet been revealed clearly enough to satisfy the requirement from field applications. In order to achieve further understanding, (1) fuzzy-ball drilling fluid was firstly prepared in the laboratory with 2.0% fuzzy-ball coating, 0.5% fuzzy-ball floss, 0.4% fuzzy-ball core, and 0.4% fuzzy-ball membrane blended by Warring Blender at 7000 rpm, whose density and apparent viscosity are respectively 0.85 g/cm 3 and 40 mPa · s , close to the in-situ reality.(2) Secondly, both uniaxial and triaxial compressive tests under 5 MPa confining pressure were conducted to measure the strengths and obtain the stress-strain curves of different coal samples after the separate injections of 2% potassium chloride solution, low solid-phase polymer drilling fluid and fuzzy-ball drilling fluid, as well as the coal plunger ( Φ 50 ) without any treatment serving as the control group respectively for three times. (3) Next, the mechanical parameters which influenced the collapse pressure were figured out with regards to sampling cores acquired from the coal reservoir. Through aforementioned experimental procedures, incorporating with a classical collapse pressure prediction mathematical model that contains these mechanical parameters, the collapse pressures corresponding to coal seams subject to different types of drilling fluids were calculated. (4) Finally, two cases, Hancheng and Qinping were employed to verify the results in the laboratory. That is, collapse and loss simultaneously took place in sites, where both issues were tackled in the same well. The findings are as follows. (1) The uniaxial compressive tests show that the strength of natural coal cores after the injection of fuzzy ball drilling fluid rises from 2.6 to 3.6 MPa in average while that after the injection of KCl displays a decline and that after the injection of polymer witnesses a modest alteration. (2) The calculation results based on the stress-strain curves illustrate that the Young's modulus ( E ), Poisson ratio ( υ ) and cohesion ( C m ) of the cores being injected with fuzzy ball drilling fluid change from 3.0665 to 3.9385 GPa , 0.229 to 0.318 and 0.5 to 0.9 MPa respectively, whereas those mechanical parameters being injected with other fluids manifest only slight changes. Similar results can be observed in the experiments with reconstructed artificial coal cores. (3) The in-situ application demonstrates that fuzzy ball drilling fluid is capable of overcoming the dilemma brought by collapse and loss taking place simultaneously in the same well. In conclusion, the wellbore instability control mechanism of CBM fuzzy ball drilling fluid lies in that through bonding formation, CBM fuzzy ball drilling fluid changes the rock mechanical parameters, enhancing the strength of rocks microscopically and thereby magnifying the safety density windows macroscopically so as to finally realize the control of wellbore instability. [ABSTRACT FROM AUTHOR]

Background: Ventricular arrhythmias (VAs) originating from the left ventricular anterobasal wall (LV-ABW) may represent a therapeutic challenge.Objective: The purpose of this study was to investigate the delayed efficacy of radiofrequency catheter (RFCA) ablation without an epicardial approach on VAs originating from the LV-ABW.Methods: Eighty patients (mean age 46.9 ± 14.9 years; 47 male) with VAs originating from the LV-ABW were enrolled. After systematic mapping of the right ventricular outflow tract, aortic root, adjacent LV endocardium, and coronary venous system, 3-4 ablation attempts were made at the earliest activation sites and/or best pace-mapping sites. Delayed efficacy was evaluated in patients with acute failure.Results: During mean follow-up of 23.8 ± 21.9 months (range 3-72 months), complete elimination of all VAs was achieved in 47 patients (59%) and partial success in 19 (24%), for an overall success rate of 83%. In 25 of 37 patients (68%) with acute failure, VAs were eliminated or significantly reduced (>80% VA burden) by the delayed effect of RFCA during follow-up. Logistic regression analysis revealed that response time to ablation was a predictor of occurrence of delayed efficacy. No complications occurred during follow-up.Conclusion: Instead of extensive ablation, waiting for delayed efficacy of RFCA may be a reasonable choice for patients with VAs arising from the LV-ABW. [ABSTRACT FROM AUTHOR]

Background: This study attempted to convert atrial fibrillation (AF) to sinus rhythm using a stepwise linear catheter ablation approach.Methods: One hundred and ninety-six patients (43 with persistent AF) were enrolled in the study. A multiple electrode array was used for anatomical navigation and activation mapping. Continuously incremental stimulation was used to induce AF if spontaneous AF was not present. Stepwise linear ablation was applied until AF was converted to sinus rhythm or atypical atrial flutter (AAFL) or atrial tachycardia (AT). The stepwise approach initially utilized a figure-7 lesion line between the right and left superior pulmonary vein on the roof of the left atrium and then extended along the ridge between the left appendage and the left pulmonary veins until the mitral valve annulus, as the primary lesions. If AF still persisted, high-frequency potentials in the inferior left atrium, coronary sinus, or right atrium were targeted. Noninducibility of AF was used as the end point.Results: AF was converted to sinus rhythm in 81.6% of patients (90.8% of paroxysmal and 51.1% of persistent AF, P<.01). The remainders of patients were converted to AAFL or AT. AF was terminated after ablation in right atrium in 7 patients. During an 18.2+/-7.3 month follow-up, 88.3% of patients were free of atrial tachyarrhythmias without medication, 9.7% of patients had refractory AAFL/AT, and only 2.1% of patients had paroxysmal AF.Conclusion: Stepwise linear ablation is effective in converting AF to sinus rhythm and the figure-7 lesion line should be the basic lesion. Right atrium ablation is necessary in some patients. [ABSTRACT FROM AUTHOR]

Background: Increased parasympathetic activity is thought to play important roles in syncope events of patients with vasovagal syncope (VVS). However, direct measurements of the vagal control are difficult. The novel deceleration capacity (DC) of heart rate measure has been used to characterize the vagal modulation. This study aimed to assess vagal control in patients with VVS and evaluate the diagnostic value of the DC in VVS.Methods: Altogether, 161 consecutive patients with VVS (43±15 years; 62 males) were enrolled. Tilt table test was positive in 101 and negative in 60 patients. Sixty-five healthy subjects were enrolled as controls. DC and heart rate variability in 24-hour ECG, echocardiogram, and biochemical examinations were compared between the syncope and control groups.Results: DC was significantly higher in the syncope group than in the control group (9.6±3.3 versus 6.5±2.0 ms, P<0.001). DC was similarly increased in patients with VVS with a positive and negative tilt table test (9.7±3.5 and 9.4±2.9 ms, P=0.614). In multivariable logistic regression analyses, DC was independently associated with syncope (odds ratio=1.518 [95% CI, 1.301-1.770]; P=0.0001). For the prediction of syncope, the area under curve analysis showed similar values when comparing single DC and combined DC with other risk factors (P=0.1147). From the receiver operator characteristic curves for syncope discrimination, the optimal cutoff value for the DC was 7.12 ms.Conclusions: DC>7.5 ms may serve as a good tool to monitor cardiac vagal activity and discriminate VVS, particularly in those with negative tilt table test. [ABSTRACT FROM AUTHOR]

Background: Circumferential pulmonary vein isolation (CPVI) often cause unavoidable vagal reflexes during procedure due to the coincidental modification of ganglionated plexus which are located on pulmonary vein (PV) antrum. The right anterior ganglionated plexi (RAGP) which located at superoanterior area of right superior PV antrum is an essential station to regulate the cardiac autonomic nerve activities and is easily coincidentally ablated during CPVI. The aim of this study is to assess the effect of RAGP ablation on vagal response (VR) during CPVI.Methods: A total of 80 patients with paroxysmal atrial fibrillation who underwent the first time CPVI were prospectively enrolled and randomly assigned to 2 groups: group A (n=40), CPVI started with right PVs at RAGP site; group B (n=40): CPVI started with left PVs first, and the last ablation site is RAGP. Electrophysiological parameters include basal cycle length, A-H interval, H-V interval, sinus node recovery time, and atrioventricular node Wenckebach point were recorded before and after CPVI procedure.Results: During CPVI, the positive VR were only observed on 1 patient in group A and 25 patients in group B (P<0.001). A total of 21 patients with positive VR in group B needed for temporary ventricular pacing during procedure, while the only patient with positive VR in group A did not need for temporary ventricular pacing (P<0.001). Compared with baseline, basal cycle length, sinus node recovery time, and atrioventricular node Wenckebach point were decreased significantly after CPVI procedure in both groups (all P<0.05) and without differences between 2 groups.Conclusions: Circumferential PV isolation initiated from RAGP could effectively inhibit VR occurrence and significantly increase heart rate during procedure. [ABSTRACT FROM AUTHOR]