A novel endocardial activation-derived predictor for focal paraseptal atrial tachycardias: Evidence from a multicenter cohort study.

BACKGROUND: The electrocardiogram-based algorithm for predicting paraseptal atrial tachycardia (PSAT) is limited by the significant overlaps in P-wave morphology originating from various paraseptal sites. OBJECTIVES: The goals of this study were to investigate the endocardial activation characteristics of PSAT and to seek an endocardial activation-derived predictor for the ablation site. METHODS: Forty-four patients [11 men (25%); mean age 62.6 ± 14.7 years] with PSAT ablation in 4 tertiary medical centers were assigned to 3 groups according to the ablation site: right atrial (RA) para-Hisian region (group 1, n = 10), noncoronary cusp (NCC) (group 2, n = 13), and left atrial (LA) paraseptal area (group 3, n = 21). Multiple-chamber activation mapping was performed guided by a 3-dimensional navigation system. The discrepancies in the earliest activation time between 2 of 3 chambers (ΔRA-LA, ΔRA-NCC, and ΔLA-NCC) were calculated in each group and used for pairwise comparisons. RESULTS: There was a significant difference in ΔRA-LA, ΔRA-NCC, and ΔLA-NCC among the 3 groups. ΔRA-LA was the only parameter that could consistently predict the ablation site of PSAT with good accuracy (area under the curve 1.000, sensitivity 100% and specificity 100%, and cutoff value 7 ms for predicting right para-Hisian or NCC ablation; area under the curve 0.974, sensitivity 92.3% and specificity 95.2%, and cutoff value -4 ms for predicting NCC or left paraseptal ablation). Based on 2 cutoff values, a 2-step algorithm was developed to predict the ablation site of PSAT with a positive predictive value of 95.4% and a negative predictive value of 97.0%. CONCLUSION: ΔRA-LA is a useful endocardial activation-derived parameter for predicting the successful ablation site of PSAT.

Characterizing the cellular and molecular variabilities of peripheral immune cells in healthy recipients of BBIBP-CorV inactivated SARS-CoV-2 vaccine by single-cell RNA sequencing.

Over 3 billion doses of inactivated vaccines for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been administered globally. However, our understanding of the immune cell functional transcription and T cell receptor (TCR)/B cell receptor (BCR) repertoire dynamics following inactivated SARS-CoV-2 vaccination remains poorly understood. Here, we performed single-cell RNA and TCR/BCR sequencing on peripheral blood mononuclear cells at four time points after immunization with the inactivated SARS-CoV-2 vaccine BBIBP-CorV. Our analysis revealed an enrichment of monocytes, central memory CD4+ T cells, type 2 helper T cells and memory B cells following vaccination. Single-cell TCR-seq and RNA-seq comminating analysis identified a clonal expansion of CD4+ T cells (but not CD8+ T cells) following a booster vaccination that corresponded to a decrease in the TCR diversity of central memory CD4+ T cells and type 2 helper T cells. Importantly, these TCR repertoire changes and CD4+ T cell differentiation were correlated with the biased VJ gene usage of BCR and the antibody-producing function of B cells post-vaccination. Finally, we compared the functional transcription and repertoire dynamics in immune cells elicited by vaccination and SARS-CoV-2 infection to explore the immune responses under different stimuli. Our data provide novel molecular and cellular evidence for the CD4+ T cell-dependent antibody response induced by inactivated vaccine BBIBP-CorV. This information is urgently needed to develop new prevention and control strategies for SARS-CoV-2 infection. (ClinicalTrials.gov Identifier: NCT04871932).

Catheter Ablation of a Right Atrial Free Wall Diverticulum-Related Accessory Pathway Masquerading as a Septal One.

Epicardial right-sided accessory pathway (AP) ablation is challenging. In rare cases, the atrial insertion of the AP is related to unconventional sites and associated with repeated and complex ablation procedures. In this study, we report a case of right free wall diverticulum-related AP with a distinct surface electrocardiogram (ECG).A 45-year-old male patient with repetitive palpitation for 2 years was referred for an electrophysiological (EP) study. His resting surface ECG showed manifest ventricular preexcitation with a negative delta wave and a "QS" wave in precordial lead V1, which is most consistent with right mid-septal AP.In the EP study, orthodromic atrioventricular reentrant tachycardia could be easily induced with the earliest atrial activation at the right atrium (RA) free wall, but the AP failed to be blocked by ablating the earliest activation on the tricuspid annulus edge. An epicardial free wall AP was then suspected.Inadvertent catheter manipulation into a narrow and long chamber was noted on the RA geometry. Angiography via contrast injection from the ablation tip revealed a diverticulum extending from the RA to the right ventricle side. The epicardial AP was suspected to be related to this diverticulum. The earliest atrial activation, as shown through a detailed activation mapping, was located at the entrance of the diverticulum. Subsequent ablation at the atrial insertion site successfully abolished the antegrade and retrograde AP conduction without any complication. A postprocedural computed tomography scan proved the presence of a free wall diverticulum associated with the right atrial appendage.A diverticulum-related AP at RA free wall might exhibit surface ECGs mimicking that of an AP at the RA septum. The approach targeting the atrial insertion of the epicardial AP is effective and might be facilitated by clarification of structural malformations prior to the ablation procedure.

Clinical application of bedside X-ray photography assistor in neonates / 中华放射医学与防护杂志

Objective:To assess the clinical application of bedside X-ray photography assistor (Patent No. 202 023 219 898.1) in neonatal bedside photography.Methods:From April 2021 to February 2022, a total of 180 pediatric patients were selected who underwent bedside chest X-ray photography in neonatal intensive care unit (NICU) of Union Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology. These patients were divided into contrpol group, consisting of 48 males and 42 females aged at (3.3 ± 2.0) d (0-10 d), and experimental group, including 50 males and 40 females aged (3.1±2.2) d (0-12 d). For chest photography, routine workflow was followed in the control group while in experimental group bedside photography protection and body position fixing device was used. The examination time, reshoot rate and image quality were compared between the two groups.Results:The diagnostic physician score and patient comfort score in the experimental group were higher than those in the control group, with statistically significant differences ( t = 3.98, 3.82, P < 0.001). The success rate in the experimental group was higher than that in the control group, with statistically significant difference ( χ2= 7.84, P < 0.05). The average time of examination in the experimental group was not significantly different from in the control group ( P>0.05 ). Conclusions:The application of bedside X-ray photography assistor in neonatal bedside photography can significantly improve the success rate and image quality and reduce the radiation dose to pediatric patients without significantly increased examination time, which is worthy of clinical application and promotion.

Prevalence, Predictors and Mechanisms of Steam Pops in Ablation Index-Guided High-Power Pulmonary Vein Isolation.

Despite the good cooling effect of the contact-force porous catheter, the risk of steam pops (SP) remains one of the major concerns in high-power circumferential pulmonary vein isolation (CPVI). This study aimed to investigate the prevalence, predictors and possible mechanisms of SPs in CPVI. Patients experiencing SPs in de novo high-power CPVI were 1:3 matched by non-SP patients with gender, age (±5 years) and left atrial diameter (LAD) (±5 mm) to compare the ablation parameters of SP and non-SP lesions. Catheter tip displacement (Tipdisp) was compared between "edge-of-ridge" and "PV-side-of-ridge" placement at anterior and roof segments of the left pulmonary vein (PV). SPs occurred in 11 (1.57%) of 701 patients, including 6 at the antero-superior left PV, 2 at the roof, 1 at the postero-superior left PV, 1 at the bottom left PV and 1 at the antero-superior aspect of the right PV. There was significantly shorter RF delivery duration (13.9 ± 6.3 vs. 23.3 ± 6.0 s), greater Δimpedance (17.6 ± 6.7 vs. 6.7 ± 4.1 Ω) and lower ablation index (357.7 ± 68.8 vs. 430.2 ± 30.7) in SP patients than those in non-SP patients. Δimpedance >12 Ω during ablation could predict SP occurrence. Tipdisp was greater in "PV-side-of-ridge" than that in "edge-of -ridge" placement (3.2 ± 1.6 mm vs. 2.0 ± 0.8 mm) at antero-superior and roof segments of the left PV. The prevalence of SP was 1.57% in high-power CPVI procedures, with the most common site at the antero-superior segment of the left PV. Δimpedance was a significant predictor of SP occurrence. "PV-side-of-ridge" ablation at antero-superior and roof segments of left PV might predispose to SP occurrence due to excessive tissue coverage.

Impact of technical aspects of vein of Marshall ethanol infusion on mitral isthmus block for persistent atrial fibrillation ablation.

Aims: Ethanol infusion into the VOM (EIVOM) adjunctive to radiofrequency catheter ablation (RFCA) was a novel approach facilitating mitral isthmus (MIth) block for persistent atrial fibrillation (PeAF); However, there were remarkable disparities in its technical aspects. This study aimed to evaluate the impact of EIVOM technical aspects on acute MIth block. Methods: Eighty consecutive patients (63 males, average age 66.4 ± 8.6 years) undergoing de novo PeAF ablation were assigned to different groups. The procedural parameters in "EIVOM first" (n = 13) or "RFCA first" (n = 13) as well as small dose ([SD], ≤4 ml, n = 26) or big dose ([BD], >4 ml, n = 54) approaches were analyzed to identify the predictors for acute MIth block. Results: Compared with the "EIVOM first" approach, the "RFCA first" approach was associated with longer procedural and MIth ablation time (134 ± 27 min vs. 112 ± 17 min; 14.9 ± 5.5 min vs. 9.3 ± 5.1 min, both P < 0.05, respectively), but with comparable success of MIth block. The ethanol dose was 6.3 ± 1.5 ml in BD group vs. 3.1 ± 1.0 ml in SD group (P < 0.001) and was correlated significantly with the size of Δlow voltage area (r = 0.66, P < 0.001). The success of MIth block was 92.6% in BD group vs. 73.1% in SD group, P = 0.03. The ethanol dose >5.75 ml independently predicted successful MIth block (OR: 0.428, 95% CI: 0.219-0.839, P = 0.01). Conclusions: Despite the comparable effectiveness on MIth block, the "EIVOM first" approach was associated with shorter procedural and MIth ablation time than the "RFCA first" approach. The ethanol dose in EIVOM was an independent predictor for MIth block.

Aucubin administration suppresses STING signaling and mitigated high-fat diet-induced atherosclerosis and steatohepatosis in LDL receptor deficient mice.

The rising obesity epidemic in developed countries is associated with many chronic inflammatory diseases including atherosclerosis and nonalcoholic steatohepatitis (NASH). Consuming aucubin may benefit health by suppressing inflammation. Herein, we studied the effects of aucubin consumption on atherosclerosis and NASH progression induced by high-fat diet (HFD) in LDL receptor deficient (LDLr-/-) mice. Adult LDLr-/- mice were fed with HFD for 12 weeks and received oral administration of aucubin for the last 6 weeks. Aucubin did not alter body weight or dyslipidemia, but lowered hyperglycemia and mitigated HFD-induced atherosclerosis and hepatic impairments in LDLr-/- mice. Aucubin administration inhibited HFD-induced inflammation and downregulated mRNA and protein expression of stimulator of IFN genes (STING) in both aortas and livers of LDLr-/- mice. In vitro, aucubin suppressed mitochondrial DNA (mtDNA)-induced activation of STING/NFκB pathway and downregulated gene expression of pro-inflammatory cytokines in cultured bone marrow-derived macrophages (BMDM). Furthermore, aucubin enhanced microRNA-181a-5p (miR-181a-5p) levels in both aortas and livers of LDLr-/- mice. Importantly, miR-181a-5p mimicked the inhibitory effect of aucubin on STING/NFκB pathway and inflammation in BMDM. In conclusion, aucubin consumption attenuated HFD-induced atherosclerosis and NASH progression in LDLr-/- mice, possibly through modulating miR-181a-5p/STING and inhibiting inflammation.

A Systemic Mapping Approach for Right and Left Parahisian Ventricular Arrhythmias Ablation.

Background: Catheter ablation for parahisian ventricular arrhythmias (PHVA) is technically challenging and associated with increased risks of atrioventricular block (AVB). We developed a systemic mapping approach to improve the efficacy and safety of PHVA ablation. Methods: Forty-three patients (29 males; average age 65.8 ± 10.5 years) with PHVAs were enrolled. A systemic mapping approach comprising differential electrocardiogram, sequential mapping, and ablation beneath/above the septal leaflet of the tricuspid valve (SLTV) and at the neighboring/contralateral regions (the aortic root and sub-aortic valve region) was applied for PHVA. The effectiveness and safety of this approach was evaluated at 1 year's follow-up. Results: Sequential ablation beneath the SLTV (B-SLTV) succeeded in 24 (66.7 %) of 36 with right PHVA and ablation above the SLTV succeeded in 6 of the remaining 12 with failed B-SLTV ablation. Target-His bundle (HB) distance > 4.5 mm significantly predicted successful right PHVA ablation (OR 1.703; 95% CI 1.084-2.676, P = 0.02). "Seeming" right PHVA by electrocardiogram in 4 and apparent left PHVA in 3 was successfully ablated at the sub-aortic parahisian region. At 1 year's follow-up, 27 (75%) of 36 patients with right PHVA and 6 (85.7%) of 7 patients with left PHVA were free of PHVA recurrence off anti-arrhythmic drugs. The total success rate was 76.7% by using the systemic mapping approach for PHVA. One patient with A-SLTV ablation underwent pacemaker implantation due to complete AVB. Conclusions: The systemic mapping approach was effective and safe for treating PHVA. The target-HB distance was a significant predictor for right PHVA ablation.

Clinical reliability of radiation protection of a neonatal bedside X-ray photography device / 中华放射医学与防护杂志

Objective:To analyze the clinical reliability of neonatal bedside photography protection and body position fixing device during neonatal bedside X-ray photography.Methods:A mobile X-ray diagnostic machine was used to project the phantom of children. The samples were divided into group A with conventional bedside photography mode, and group B using neonatal bedside X-ray photography protection device. X-ray diagnostic level dosimeters were placed at the projection and radiation sensitive sites, respectively. The three parts of the chest, pelvis and skull were used as the projection center, and the radiation dose to the projection site and the radiation sensitive site were collected and recorded, and the statistical analysis was carried out.Results:When the chest was taken as the center of the projection, the radiation doses to the lens of the eye, thyroid and gonad in the body model group B of children were 94.4%, 96.9% and 96.7% lower than those in the non-injected part of group A, respectively ( t=-152.55, -445.16, -129.07, P<0.05). When the pelvis was taken as the projection center, the radiation doses to the lens, thyroid and thymus in the body model group B were 85.5%, 87.1% and 94.9% lower than those in the non-projection part of group A, respectively ( t=-50.68, -194.18, -535.94, P<0.05). When the head was taken as the projection center, the radiation doses to thyroid, thymus and gonad in the body model group B were 99.3 %, 97.4 % and 94.3 % lower than those in the non-projection position of group A, respectively ( t=-1 859.97, -542.08, -66.26, P< 0.05). Conclusions:The use of neonatal bedside photography protection and position fixing device during neonatal bedside X-ray photography can significantly reduce the radiation dose to children in non-projected areas under the premise of ensuring image quality. At the same time, it can fix and protect the children, improve the success rate of examination, being worthy of clinical promotion.

Macro-reentrant atrial tachycardia after tricuspid or mitral valve surgery: is there difference in electrophysiological characteristics and effectiveness of catheter ablation?

BACKGROUND: Macro-reentrant atrial tachycardias (MATs) are a common complication after cardiac valve surgery. The MAT types and the effectiveness of MAT ablation might differ after different valve surgery. Data comparing the electrophysiological characteristics and the ablation results of MAT post-tricuspid or mitral valve surgery are limited. METHODS: Forty-eight patients (29 males, age 56.1 ± 13.3 years) with MAT after valve surgery were assigned to tricuspid valve (TV) group (n = 18) and mitral valve (MV) group (n = 30). MATs were mapped and ablated guided by a three-dimensional navigation system. The one-year clinical effectiveness was compared in two groups. RESULTS: Nineteen MATs were documented in TV group, including 16 cavo-tricuspid isthmus (CTI)-dependent AFL and 3 other MATs at right atrial (RA) free wall, RA septum and left atrial (LA) roof. Thirty-nine MATs were identified in MV group, including15 CTI-dependent AFL, 8 RA free wall scar-related, 2 RA septum scar-related, 8 peri-mitral flutter, 3 LA roof-dependent, 2 LA anterior scar-related, and 1 right pulmonary vein-related MAT. Compared with TV group, MV group had significantly lower prevalence of CTI-dependent AFL (38.5% vs. 84.2%), higher prevalence of left atrial MAT (35.9 vs.5.3%) and higher proportion of patients with left atrial MAT (40 vs. 5.6%), P = 0.02, 0.01 and 0.01, respectively. The acute success rate of MAT ablation (100 vs. 93.3%) and the one-year freedom from atrial tachy-arrhythmias (72.2 vs. 76.5%) was comparable in TV and MV group. No predictor for recurrence was identified. CONCLUSION: Although the types of MATs differed significantly in patients with prior TV or MV surgery, the acute and mid-term effectiveness of MAT ablation was comparable in two groups. TRIAL REGISTRATION: This study was registered as a part of EARLY-MYO-AF clinical trial at the website ClinicalTrials. gov (NCT04512222).