Efficacy and safety of pulsed field ablation for accessory pathways: a pilot study.

AIMS: Radiofrequency ablation is used as a first-line therapy for accessory pathways (APs). However, data regarding the effects of pulsed field ablation (PFA) on APs are limited. We sought to evaluate the acute procedural and 6-month success and safety of PFA in a cohort of patients with APs. METHODS AND RESULTS: A focal contact force-sensing PFA catheter was used for patients with APs. Pulsed field ablation generator generated a bipolar and biphasic waveform (±1000 V) with a duration of 100 ms from the tip of the PFA catheter. A 100% acute procedural success was achieved in 10 conscious patients with APs (7 left anterolateral, 2 left inferolateral, and 1 right posteroseptal APs) including 6 (60%) patients after an initial application. The average total ablation time was 6.3 ± 4.9 s for 4.7 ± 1.8 ablation sites (ASs), including 3.1 ± 2.4 s at targets and 3.2 ± 2.9 s at 3.2 ± 2 bolus ASs. The mean skin-to-skin time was 59.3 ± 15.5 min, and PFA catheter dwell time was 29.4 ± 7.8 min. One patient encountered transient sinus arrest during PFA due to parasympathetic overexcitation. Sinus rhythm was restored in all patients without any significant adverse events during the short-term follow-up. CONCLUSION: Pulsed field ablation of APs was feasible, effective, and safe. Its efficiency was remarkable for its ultrarapid termination of AP conduction. Further studies are warranted to prove whether utilization of PFA with current parameters can extend to manifold AP ablation.

Impact of left atrial appendage orifice diameter on the safety and efficacy of left atrial appendage closure using the LAmbre device.

BACKGROUND: The diameter and shape of the left atrial appendage (LAA) orifices may influence occluder selection and the outcomes of left atrial appendage closure (LAAC) procedure. This study aimed to evaluate the impact of LAA orifice diameter on the safety and efficacy of LAAC using the LAmbre device. METHODS: A total of 133 patients with nonvalvular atrial fibrillation (AF) who underwent LAAC with the LAmbre device between June 2018 and June 2020 were included in this study. The patients were categorized into two groups based on the maximal diameter of the LAA orifice: the large LAA group (n = 45) with a maximal orifice diameter of ≥31 mm, and the normal LAA group (n = 88) with a maximal orifice diameter of <31 mm. The study assessed periprocedural characteristics and long-term clinical follow-up. RESULTS: Successful implantation of the LAmbre device was observed in all patients. The incidence of periprocedural peridevice leakage (PDL) was significantly higher in the large LAA group (P < 0.001), while the incidence of acute pericardial effusion (PE) during the procedure was comparable between the two groups (P = 1.000). After a mean follow-up period of 4.8 ± 1.7 years, three patients in the large LAA group developed delayed PE, while no patients in the normal LAA group did (P = 0.037). Additionally, a larger LAA maximal orifice diameter was associated with a higher prevalence of PDL (P = 0.001) and PE (including both acute and delayed PE) (P = 0.027). The optimal cutoff value of the LAA maximal orifice diameter for predicting PDL and PE after LAAC with the LAmbre device was determined to be 30 mm. CONCLUSION: The findings suggest that the LAmbre device is a safe and feasible option for occluding the LAA, regardless of its orifice diameter. However, it is important to note that a larger LAA orifice diameter may increase the risk of PDL and delayed PE.

Enhancement of Mass Transfer Process for Photocatalytic Reduction in Cr(VI) by Electric Field Assistance.

The removal of Cr(VI), a highly-toxic heavy metal, from industrial wastewater is a critical issue in water treatment research. Photocatalysis, a promising technology to solve the Cr(VI) pollution problem, requires urgent and continuous improvement to enhance its performance. To address this need, an electric field-assisted photocatalytic system (PCS) was proposed to meet the growing demand for industrial wastewater treatment. Firstly, we selected PAF-54, a nitrogen-rich porous organic polymer, as the PCS's catalytic material. PAF-54 exhibits a large adsorption capacity (189 mg/g) for Cr(VI) oxyanions through hydrogen bonding and electrostatic interaction. It was then coated on carbon paper (CP) and used as the photocatalytic electrode. The synergy between capacitive deionization (CDI) and photocatalysis significantly promotes the photoreduction of Cr(VI). The photocatalytic performance was enhanced due to the electric field's influence on the mass transfer process, which could strengthen the enrichment of Cr(VI) oxyanions and the repulsion of Cr(III) cations on the surface of PAF-54/CP electrode. In addition, the PCS system demonstrates excellent recyclability and stability, making it a promising candidate for chromium wastewater treatment.

Delayed pericardial effusion or tamponade following left atrial appendage closure: A single-center experience.

BACKGROUND: Pericardial effusion or pericardial tamponade (PE/PT) is a relatively common complication of left atrial appendage closure (LAAC). However, delayed PE/PT is rare with limited data. The aim of the study was to analyze the incidence and clinical consequences of delayed PE/PT following LAAC. METHODS: Patients with nonvalvular AF who were successfully implanted with LAAC devices from October 2014 to April 2021 were consecutively screened. Subjects experiencing delayed PE/PT after LAAC were included. All treatment sessions of the subjects were recorded in detail. After discharge, the patients were followed up for clinical outcomes. RESULTS: A total of 748 patients with successful LAAC [nitinol cage device (475 Watchman 2.5), nitinol plug device (131 ACP and 142 LAmbre)] were screened. Six patients experienced delayed PE/PT (1 Watchman, 2 ACP, 3 LAmbre). The incidence of delayed PE/PT was higher in patients with a nitinol plug device (1.8% vs. 0.2%, P = 0.027). Bloody PE only occurred in patients with a nitinol plug device (5/273, 1.8%). All the patients accepted pericardiocentesis and discontinuing antithrombotic medication, and none of the patients died or needed cardiac surgery. All patients were followed up for 810 (598, 1174) days after discharge. None of them developed constrictive pericarditis or thromboembolic or major bleeding events. CONCLUSION: Delayed PE/PT is rare but can occur, and the incidence of delayed bloody PE/PT for the nitinol plug device was higher than that for the nitinol cage device. The strategy of emergency pericardiocentesis combined with discontinuing antithrombotic medication may be effective for delayed bloody PE/PT.

Safety and efficacy of low-dose non-vitamin K antagonist oral anticoagulants versus warfarin after left atrial appendage closure with the Watchman device.

BACKGROUND/PURPOSE: Anticoagulant therapy is suggested within 45 days after Watchman device implantation for stroke prevention in patients with atrial fibrillation (AF). A previous study demonstrated that non-vitamin K antagonist oral anticoagulants (NOACs) were a feasible peri- and postprocedural alternative to warfarin. The present study aimed to compare the safety and efficacy of using different anticoagulants (low-dose NOACs vs. warfarin) within 45 days after Watchman device implantation in a Chinese population. METHODS: Patients with successful Watchman device implantation from October 2014 to June 2020 were included. All patients received anticoagulants within 45 days after the procedure, and those patients were divided into three groups according to the type of postprocedural anticoagulants. Transesophageal echocardiography follow-up was performed 45 days post procedure to assess residual flow and the occurrence of device-related thrombus (DRT). RESULTS: A total of 368 patients were enrolled in the study. The study population was divided into three groups: the warfarin group (n = 77), the dabigatran group (n = 165) and the rivaroxaban group (n = 126). Periprocedural major bleeding was higher in the warfarin group (2.6% vs. 0% vs. 0%, P = 0.043), while minor bleeding was comparable among the groups (3.9% vs. 1.2% vs. 0.8%, P = 0.230). No periprocedural transient ischemic attack/stroke occurred. At follow-up, the incidence of DRT was higher in the warfarin group than in the other groups (4.2% vs. 0.6% vs. 0.8%; P = 0.116), but the difference was not statistically significant. The rates of thromboembolic and bleeding events were similar in the three groups. CONCLUSION: The safety and efficacy of low-dose dabigatran and rivaroxaban were comparable to those of warfarin within 45 days after Watchman device implantation in a Chinese population.

LPS induces cardiomyocyte necroptosis through the Ripk3/Pgam5 signaling pathway.

Necroptosis is a new type of cell death. However, the role of necroptosis in LPS-related cardiomyocyte damage has not been fully understood. The aim of our study is to explore the molecular mechanism underlying inflammation-mediated cardiomyocyte necroptosis. H9C2 cardiomyocyte cell line was treated with LPS. Then, cell viability and necroptosis were measured through qPCR and ELISA. Pathway analysis was performed to verify whether Ripk3/Pgam5 signaling pathway is implicated into the regulation of cardiomyocyte necroptosis. The results demonstrated that LPS reduced cardiomyocyte viability and activated necroptosis. At the molecular levels, oxidative stress and inflammation were triggered by LPS and these alterations may contribute to the activation of necroptosis. Finally, we found that Ripk3/Pgam5 signaling pathway was activated by LPS in cardiomyocyte and this signaling pathway may explain the regulatory mechanism underlying LPS-mediated necroptosis. Altogether, our results demonstrated that septic cardiomyopathy is associated with an activation of necroptosis through the Ripk3/Pgam5 signaling pathway.

Percutaneous Left Atrial Appendage Closure Confirmed by Intra-Procedural Transesophageal Echocardiography under Local Anesthesia: Safety and Clinical Efficacy.

BACKGROUND: Percutaneous left atrial appendage closure (LAAC) is usually performed under general anesthesia (GA) guided by transesophageal echocardiography (TEE), or under local anesthesia (LA) guided by intracardiac echocardiography (ICE). GA is known to carry some disadvantages. It is sometimes technically challenging to obtain adequate imaging of the left atrial appendage (LAA) with LAAC guided by ICE. This study aimed to assess the safety and clinical efficacy of LAAC guided by TEE under LA in patients with non-valvular atrial fibrillation (AF). METHODS: A total of 159 patients (70.5 ± 8.2 years; 66% male) with AF who had a high risk of stroke and bleeding or who had contraindications for oral anticoagulation underwent LAAC under LA. TEE or computed tomography (CT) follow-up was scheduled approximately 6 weeks after the procedure. Patients were followed to assess ischemic stroke and major bleeding events. RESULTS: The LAA was successfully occluded in 152 patients (95.6%). There were 2 (1.3%) periprocedural major adverse events. A total of 142 patients (93.4%) finished TEE or CT follow-up. Thrombus formation as seen on the device was documented in 2 patients. All of the LAAs were completely sealed with the absence of flow or with minimal flow. The median follow-up period was 522 days, resulting in a total of 216 patient-years. Ischemic stroke occurred in 4 patients. The annual ischemic stroke rate was 1.9/100 person-years. Major bleeding occurred in 2 patients. The annual major bleeding rate was 1.9/100 person-years. CONCLUSIONS: In this study, percutaneous LAAC using TEE under LA was safe and showed encouraging results for stroke prevention and major bleeding reduction.

Left atrial appendage closure with zero fluoroscopic exposure via intracardiac echocardiographic guidance.

BACKGROUND/PURPOSE: Left atrial appendage closure (LAAC) is conventionally guided by fluoroscopy and transesophageal echocardiography. We introduce an LAAC technique without fluoroscopy exposure using intracardiac echocardiography (ICE) and electroanatomic mapping system (EAMS) under local anesthesia. METHODS: Seven non-valvular atrial fibrillation patients who underwent LAAC with the LAmbre devices under the ICE and EAMS guidance were compared to 7 patients following the conventional approach by propensity score matching. ICE probe was advanced into the left atrium (LA) to guide sizing and device implantation following the orthogonal tri-axial technique (Axis-X: from left pulmonary veins [PVs] to LAA; Axis-Y: from right PV ostium to LAA; Axis-Z: from lower LA to LAA). RESULTS: The mean diameters of ostia and landing zone were 21.4 ± 3.9 mm and 20.4 ± 4.2 mm, respectively. LAmbre devices with a mean umbrella diameter of 23.7 ± 4.2 mm and cover disc diameter of 29.4 ± 3.6 mm were successfully implanted and acute complete LAA sealing without peri-device leak (PDL) were achieved in all cases. Neither fluoroscopy exposure nor contrast consumption was recorded. No procedure related complications were documented. The mean procedural time and PDLs at follow-ups were comparable to those in the conventional group. No stroke or thromboembolic events were documented. CONCLUSION: The fluoroscopy exposure could be minimized, even to zero, in the ICEguided LAAC procedures feasibly and safely using LAmbre devices. The orthogonal triaxial technique is considered efficacious and safe for the procedures.

Association of Left Atrial Appendage Voltage with Ischemic Stroke in Patients with Atrial Fibrillation.

BACKGROUND: Low atrial voltage is associated with an increased risk of stroke. The relationship between left atrial appendage voltage (LAAV) and ischemic stroke remains unknown. Low LAAV may predict the prevalence of ischemic stroke in patients with atrial fibrillation (AF). METHODS: A total of 1108 patients with AF referred for catheter ablation were consecutively included from January 2015 to May 2018. The patients were divided into stroke and control groups based on previous ischemic stroke by neuroimaging criteria. LAAV was measured with a circular mapping catheter in sinus rhythm after ablation. Variables were compared, and logistic regression was performed to assess the relationship between LAAV and stroke. RESULTS: A total of 120 patients (10.8%) had a history of ischemic stroke. The patients in the stroke group were older and had higher percentages of hypertension, diabetes mellitus and coronary/vascular disease. The CHA2DS2-VASc score was higher and left atrial diameter was larger in the patients with stroke. More left atrial appendage thrombi and spontaneous echo contrast were detected in the stroke group. LAAV was significantly lower in the stroke group compared with the controls (5.3 ± 1.8 mV vs. 6.5 ± 1.8 mV; p < 0.001). Multivariate logistic regression revealed that a lower LAAV was associated with increased stroke prevalence [odds ratio = 0.75; 95% confidence interval (CI) 0.65-0.87; p < 0.001]. LAAV had a predictive value, with an area under the curve of 0.83 (95% CI 0.79-0.87; p < 0.001). With an optimal cut-off value of 5.2 mV for LAAV, the sensitivity and specificity were 75% and 74%, respectively. CONCLUSIONS: Lower LAAV in AF patients was associated with increased ischemic stroke prevalence. Whether LAAV is related to incident stroke requires further studies.

Optimal combination strategy of left atrial appendage closure plus catheter ablation in a single procedure in patients with nonvalvular atrial fibrillation.

BACKGROUND: The efficacy and safety of combining left atrial appendage closure (LAAC) plus atrial fibrillation (AF) catheter ablation (CA) in a single procedure has been established, but the optimal combination strategy has not been thoroughly elucidated to date. OBJECTIVE: We aimed to investigate the impact of different combination strategies on clinical outcomes. METHODS: Eighty-two consecutive patients with symptomatic AF (mean CHA2 DS2 -VASc score 4.4 ± 1.4, mean HAS-BLED score 3.5 ± 1.0) were enrolled. LAAC with the Watchman device was performed either before (occlusion-first group, N  =  52) or after (ablation-first group, N  =  30) CA. Procedural and clinical data were retrospectively analyzed to evaluate the advantages of each strategy. RESULTS: Complete device occlusions were achieved in 92.3% and 90.0% of patients, respectively (P  =  0.719). Neither acute nor chronic peridevice leak greater than 5 mm was detected. Oral anticoagulants were held in all patients, except two (one in each group) with asymptomatic device-related thrombi. AF-free success rates were comparable between groups with a mean follow-up of 11.2 ± 7.3 months (75.0% vs. 70.0%, log-rank P  =  0.311). The new peridevice leak rate was significantly lower in the occlusion-first group (7.7% vs. 26.7%, P  =  0.019). Multivariate logistic regression demonstrated that the combination strategy was independently associated with the new peridevice leak (P  =  0.025, OR 13.3). CONCLUSIONS: Both occlusion-first and ablation-first strategies were efficacious and safe as combined procedures in patients with nonvalvular AF; however, the occlusion-first strategy was associated with lower new peridevice leak rates at follow-up.

Evaluation of somatic embryos of alfalfa for recombinant protein expression.

KEY MESSAGE: Somatic embryos of alfalfa can accumulate higher levels of recombinant proteins comparing to vegetative organs. Somatic embryos may be explored as a new system for new protein production for plants. Plants have been explored via genetic engineering as an inexpensive system for recombinant protein production. However, protein expression levels in vegetative tissues have been low, which limits the commercial utilization of plant expression systems. Somatic embryos resemble zygotic embryos in many aspects and may accumulate higher levels of proteins as true seed. In this study, somatic embryo of alfalfa (Medicago sativa L.) was investigated for the expression of recombinant proteins. Three heterologous genes, including the standard scientific reporter uid that codes for ß-glucuronidase and two genes of interest: ctb coding for cholera toxin B subunit (CTB), and hIL-13 coding for human interleukin 13, were independently introduced into alfalfa via Agrobacterium-mediated transformation. Somatic embryos were subsequently induced from transgenic plants carrying these genes. Somatic embryos accumulated approximately twofold more recombinant proteins than vegetative organs including roots, stems, and leaves. The recombinant proteins of CTB and hIL-13 accumulated up to 0.15 and 0.18 % of total soluble protein in alfalfa somatic embryos, respectively. The recombinant proteins expressed in somatic embryos also exhibited biological activities. As somatic embryos can be induced in many plant species and their production can be scaled up via different avenues, somatic embryos may be developed as an efficient expression system for recombinant protein production.

Investment analysis of the private firm under different financial arrangements in infrastructure projects.

This study investigates the impact of various financial arrangements on the investment behavior of the private firm in PPP (Public-Private Partnership) projects. The results manifest that: first, the private firm will invest in the project earlier under long-term debt financing than under short-term debt financing or all equity financing; second, the investment boundary of the private sector decreasing with the probability of obtaining long-term debt financing under short-term debt financing, while increasing with the probability of obtaining long-term debt financing under long-term debt financing; third, the optimal debt level under short-term debt financing displays a U-shaped relationship with the refinancing risk probability; fourth, under short-term debt financing, the difference in the optimal capital structure between projects with different volatility of cash flow is larger when the refinancing risk probability is lower; and fifth, the private firm may exit the project earlier under short-term debt financing than under long-term debt financing. These results can help us to understand the investment behavior of the private firm under different financial arrangements.

Clinical outcomes of combined catheter ablation and left atrial appendage closure in elderly patients with nonvalvular atrial fibrillation.

BACKGROUND: Catheter ablation (CA) combined with left atrial appendage closure (LAAC) has emerged as a promising method to relieve symptoms while reducing the incidence of stroke in selected high-risk patients with atrial fibrillation (AF). HYPOTHESIS: We aimed to investigate the clinical outcomes of combined CA and LAAC in elderly patients. METHODS: A total of 316 patients with symptomatic drug-refractory AF who underwent combined CA and LAAC between January 2016 and December 2020 were retrospectively included. Baseline characteristics, periprocedural complications, and clinical events during follow-up were recorded and compared between patients aged ≥ 75 years (n = 66) and <75 years (n = 250). RESULTS: Pulmonary vein isolation and satisfactory LAAC were achieved in all patients. No patients experienced death or stroke/transient ischemic stroke periprocedurally. After a median follow-up of 12.2 (6.7-24.4) months and 11.9 (5.5-23.6) months, the rate of sinus rhythm maintenance was comparable between the two groups (≥75 years: 78.8% vs. <75 years: 80.8%; log-rank test, p = 0.674). The median follow-up periods for clinical outcomes were 27.9 (9.3-44.8) months and 25.2 (10.8-45.7) months, respectively. In patients aged ≥ 75 years, one suffered ischemic stroke, and one experienced major bleeding event. In patients aged < 75 years, four had ischemic stroke, and eight had major bleeding events. Two patients aged < 75 years died during follow-up, while none of the patients aged ≥ 75 years died. CONCLUSIONS: Combining CA and LAAC was feasible, safe and effective in elderly patients with AF.

Left atrial appendage closure in patients with left atrial appendage thrombus guided by intracardiac echocardiography.

BACKGROUND: Data regarding left atrial appendage closure (LAAC) in patients with left atrial appendage (LAA) thrombus are limited. Recently published cases have mostly been guided by transesophageal echocardiography. Intracardiac echocardiography (ICE) is now widely used during LAAC procedures. OBJECTIVE: This is the first study to report the feasibility of LAAC in patients with LAA thrombus guided by ICE. METHODS: Patients with persistent LAA thrombus despite anticoagulation or contraindications to anticoagulation who underwent a modified ICE-guided LAAC procedure between June 2021 and April 2023 were included. Periprocedural events and clinical outcomes during follow-up were recorded. RESULTS: A total of 12 patients (mean age 65 ± 7 years; 92% male) were included: 10 with persistent LAA thrombus and 2 with contraindications to anticoagulation. Most of the thrombus was at the apex (n = 6), followed by the body (n = 3) and the ostium (n = 3). A LAmbre device was used and successfully implanted in all patients with the guidance of ICE. No thrombotic material was retrieved from patients with the protection of cerebral protection device (n = 11). No patient experienced severe periprocedural complications. All patients completed transesophageal echocardiography follow-up, and no device-related thrombus or peridevice leak > 3 mm was detected. None of the patients experienced stroke/transient ischemic attack, systemic embolism, or major bleeding events during a median follow-up of 147 days (interquartile range 80-306 days). CONCLUSION: LAAC using the LAmbre device guided by ICE may be feasible in patients with LAA thrombus when performed by experienced operators.

Outcomes of Focal Pulsed Field Ablation for Paroxysmal Supraventricular Tachycardia.

BACKGROUND: Pulsed field ablation (PFA) is primarily used for treatment of atrial fibrillation as it provides better safety and efficacy. However, there are limited data available on the use of PFA for paroxysmal supraventricular tachycardia (PSVT). The study sought to describe the outcomes of PSVT ablation with a novel focal contact force (CF)-sensing PFA. METHODS: In this first-in-human pilot study, a focal CF-sensing PFA catheter was used for mapping and ablation navigated with an electroanatomic mapping system (EAMS). Pulsed field energy was delivered as biphasic/bipolar electrical pulse trains with 2000 V/delivery. CF was controlled from 2 g to 10 g during PFA. RESULTS: Procedural acute success was achieved without general anaesthesia or conscious sedation in all 10 patients, including 7 patients diagnosed with typical atrioventricular nodal re-entrant tachycardias and 3 patients with orthodromic reciprocating tachycardias. Successful target ablation time was 2.0 ± 0.5 seconds per patient, and the acute procedural success at the first single site was achieved in 5 patients. The mean skin-to-skin procedure time was 79.4 ± 15 minutes, PFA catheter dwell time was 50.1 ± 14 minutes, and fluoroscopy time was 6.2 ± 7 minutes. Maintenance of sinus rhythm was observed in all patients within 6-month follow-up. No serious adverse events occurred in any subjects during PFA or during the 6-month follow-up. CONCLUSIONS: A focal CF-sensing PFA catheter could effectively, rapidly, and safely ablate PSVT in conscious patients. CLINICAL TRIAL REGISTRATION: NCT05770921.

Unexpected transient atrioventricular block and slow junctional rhythm using pulsed field ablation for slow pathway modification: excited or cautious for ablators.

BACKGROUND: Data regarding the effects of pulsed field ablation (PFA) on atrioventricular nodal reentrant tachycardia (AVNRT) are limited. OBJECTIVE: To evaluate the outcomes of PFA for AVNRT, and its impact on dual-pathway electrophysiology. METHODS: A larger cohort of patients with typical AVNRT underwent slow pathway (SP) modification (SPM) using a focal PFA catheter in a biphasic/bipolar manner. The primary endpoints were the efficacy and safety of PFA during the procedure and 6-month follow-up. RESULTS: The acute success of SPM was achieved in all 40 patients. The total ablation time was 7.9±3.8 seconds for 6.4±2.2 ablation sites (ASs). Slow junctional rhythm (SJR) was induced in 32 (80%) patients lasting 28.9±10.3 seconds in 3.0±1.1 ASs per patient. SP was located 11.1±1.2 mm from the largest His activation (LHA). At 9 ASs, SJR could be reinduced after an increase of contact force (CF) from 1.3±0.5g to 6.4±1.3g (P<0.0001). Transient atrioventricular block (AVB) was recorded in 7(17.5%) patients (1 second-degree and 6 third-degree AVB) lasting 435.3±227.4 seconds, with a shorter AS-LHA distance than patients without AVB (7.7±0.6 mm vs. 11.3±1 mm, P<0.0001). PFA-related delayed atrial-His (n=6) and His-atrial (n=1) conduction preceded transient AVB with a constant His-ventricular interval. Normal PR interval was restored within 24 hours. All patients maintained sinus rhythm without any significant adverse events during 6-month follow-up. CONCLUSION: Despite the high efficiency of PFA for SPM, the notable incidence of transient AVB warranted caution when applying it near the His bundle. SJR frequently occurred during SPM and was dependent on moderate CF.

Pericardial effusion following percutaneous left atrial appendage closure using the LAmbre device.

Background: Pericardial effusion (PE) is an uncommon but serious complication that occurs following percutaneous left atrial appendage closure (LAAC). There are few data regarding PE following implantation of the LAmbre device for LAAC. Methods: Patients with nonvalvular atrial fibrillation (AF) undergoing percutaneous LAAC using the LAmbre device at the Arrhythmia Center of Ningbo First Hospital from October 2017 to March 2021 were retrospectively reviewed (n = 133). PE was defined as acute if diagnosed ≤7 days post LAAC (n = 3, 2.3%) or delayed if diagnosed >7 days post LAAC (n = 3, 2.3%). The clinical characteristics and procedural data were compared between patients with PE (PE group, n = 6) and without PE (non-PE group, n = 127). The predictors of PE were analyzed by logistic regression. Results: All patients with PE recovered following treatment by pericardiocentesis. Patients with PE were found to have a higher incidence of congestive heart failure (50.0% vs. 13.4%, P = 0.044) and had larger measured LAA orifice diameters (33.5 mm ± 6.0 mm vs. 28.3 mm ± 5.2 mm, P = 0.018) and landing zone diameters (27.8 mm ± 4.8 mm vs. 23.9 mm ± 4.8 mm, P = 0.054) compared with those without PE. The diameters of the device umbrellas (31.7 mm ± 5.6 mm vs. 26.9 mm ± 5.0 mm, P = 0.026) and covers (36.3 mm ± 4.6 mm vs. 33.4 mm ± 4.0 mm, P = 0.075) implanted were larger in the PE group compared to the non-PE group. Univariate logistic regression revealed that congestive heart failure (OR = 6.47, 95% CI = 1.21-34.71, P = 0.029) and LAA maximal orifice diameter (OR = 1.22, 95% CI = 1.02-1.45, P = 0.027) were both associated with PE following LAmbre device implantation. Conclusions: In this single-center experience, both acute and delayed PE were uncommon in patients with AF following LAmbre device implantation. Congestive heart failure and a larger LAA orifice were identified as predictors for the occurrence of PE.

The impact of empirical Marshall vein ethanol infusion as a first-choice intraoperative strategy on the long-term outcomes in patients with persistent atrial fibrillation undergoing mitral isthmus ablation.

Background: Marshall vein ethanol infusion (MVEI) as an additional therapy to conventional catheter ablation (CA) has been proved to be efficacious in patients with persistent atrial fibrillation (PeAF). However, whether empirical MVEI could be the first-line strategy in mitral isthmus (MI) ablation has seldom been investigated. Here, we aim to compare the efficacy, safety, and long-term outcomes between provisional and empirical MVEI in PeAF patients undergoing the index MI ablation procedure. Methods: We enrolled 133 patients with PeAF either in the provisional group (n = 38, MVEI was performed when conventional endocardial and/or epicardial ablation procedures were inadequate to achieve bidirectional MI block) or in the empirical group (n = 95, MVEI was performed empirically before MI CA). Results: All of the baseline characteristics were comparable. Less spontaneous or inducible atrial tachycardias (ATs) were encountered in the empirical group of patients (P < 0.001). More epicardial ablations were applied (26.3% vs. 9.5%, P = 0.016) and a higher incidence of CA-facilitated restoration of sinus rhythm was recorded (86.8% vs. 11.7%, P < 0.001) in the provisional group of patients. Although more fluoroscopy time (6.4[4.2, 9.3] vs. 9.5[5.9, 11.6] min, P = 0.019) and radiation exposure (69.0[25.3, 160.2] vs. 122.0[62.5, 234.1] mGy, P = 0.010) were documented in the empirical group with comparable procedure time, less time (455.9 ± 192.2 vs. 366.5 ± 161.3 s, P = 0.038) was consumed to achieve bidirectional MI block during endocardial ablation in the provisional group. Incidences of procedure-related complications were similar between the two groups. During a 16.5 ± 4.4-month follow-up, the empirical group of patients showed a significantly higher rate of freedom from AT recurrence (95.8% vs. 81.6%, log-rank P = 0.003), while the rate of freedom from AF or atrial tachyarrhythmias (combining AF and AT) was similar. Both univariate (HR 0.19, 95% CI 0.05-0.64, P = 0.008) and multivariate (HR 0.25, 95% CI 0.07-0.92, P = 0.037) Cox regression analyses indicated that empirical MVEI was independently associated with lower long-term AT recurrence. Conclusion: Among patients with PeAF who underwent the index MI ablation procedure, empirical MVEI could reduce endocardial MI ablation time and provide greater long-term freedom from AT recurrence.

Long-term safety and efficacy of left atrial appendage closure in patients with small appendage orifices measured with transesophageal echocardiography.

BACKGROUND: The Watchman device is the most widely used occluder but is indicated in atrial fibrillation (AF) patients with a maximal left atrial appendage (LAA) orifice diameter between 17 and 31 mm. We aimed to compare the long-term safety and efficacy of left atrial appendage closure (LAAC) between patients with a small LAA (<17 mm) and those with an indicated LAA (17-31 mm) measured by transesophageal echocardiography (TEE). METHODS: A total of 369 AF patients treated with LAAC between March 2015 and February 2019 were included and divided into two groups based on the maximal LAA orifice diameter measured by TEE: small LAA group (n = 22) and indicated LAA group (n = 347). Periprocedural complications and long-term clinical outcomes were compared. RESULTS: The Watchman device was successfully implanted in all patients. Mean device compression was higher in the small LAA group. Four patients (1.2%) in the indicated LAA group experienced pericardial effusion, and none experienced pericardial effusion in the small LAA group. Device-related thrombus was detected in one (4.5%) patient in the small LAA group and five (1.4%) in the indicated LAA group (p = .310). After a mean follow-up period of 4.1 ± 1.6 years, one patient in the small LAA group (4.5%; 1.1/100 person-years) and four in the indicated LAA group (1.2%; 0.3/100 person-years) suffered an ischemic stroke (p = .266). CONCLUSIONS: The safety and efficacy of LAAC with the Watchman device were comparable between patients with small and indicated LAA orifice diameters measured by TEE.

The Prognostic Nutritional Index May Predict Left Atrial Appendage Thrombus or Dense Spontaneous Echo Contrast in Patients With Atrial Fibrillation.

Objectives: The prognostic nutritional index (PNI) is an independent predictor of adverse outcomes in patients with cardiovascular diseases. The presence of left atrial appendage thrombus (LAAT) or spontaneous echo contrast (SEC) is associated with ischemic stroke. The present study aimed to investigate the relationship between the PNI and LAAT/dense SEC in patients with non-valvular atrial fibrillation (AF). Methods: In patients with non-valvular AF, we compared demographics, clinical characteristics, and prevalence of LAAT/dense SEC according to the levels of the PNI. The relationship between the PNI and LAAT/dense SEC was observed. Results: A total of 406 patients with non-valvular AF were consecutively included from March 2015 to February 2019. Of the study population, 53 patients had LAAT/dense SEC. The percentages of LAAT/dense SEC were 20.4, 14.1, and 4.5% in subjects from the lowest to the highest tertile of the PNI, respectively. Multivariate logistic analysis demonstrated that the PNI was an independent predictor for LAAT/dense SEC (OR 0.89; 95% CI, 0.82-0.97; P = 0.007). Receiver operating characteristic curve analysis revealed that the optimal cutoff value of the PNI for predicting LAAT/dense SEC was 48.0 (area under the curve: 0.68; 95% CI, 0.61-0.75; P < 0.001). The sensitivity and specificity were 83.0 and 47.6%, respectively. The risk of LAAT/dense SEC in patients with a PNI ≤ 48.0 was 2.57-fold higher than that in those with a PNI > 48.0. Conclusion: The PNI, calculated based on serum albumin and lymphocyte count, was inversely correlated with LAAT/dense SEC in patients with non-valvular AF. Therefore, it may be considered a predictor for LAAT/dense SEC.