Real world risk of discontinuing oral anticoagulation after successful catheter ablation for atrial fibrillation.

Background: Many patients with atrial fibrillation (AF) discontinued oral anticoagulation (OAC) therapy after successful catheter ablation. We aimed to determine the real-world risks and consequences of discontinuing OAC use after catheter ablation for AF. Methods: Patients who underwent successful catheter ablation for AF from January 2004 to December 2020 were divided into continued long-term OAC (On-OAC, n = 1062) and discontinued (Off-OAC, n = 1055) groups. The long-term outcomes including thromboembolic events, major bleeding, all-cause mortality and major adverse cardiovascular events (MACE), were compared between the two groups. Results: The CHA2DS2-VASc score was 3.44 ± 1.12. After a mean follow-up of 37.09 months, thromboembolism risk was higher and major bleeding risk was lower in the Off-OAC than in the On-OAC group (Both log-rank P < 0.001). CHA2DS2-VASc score-stratified subgroup analysis showed similar cumulative event rates between the two groups in men and women with scores of 2 and 3 (intermediate risk for stroke), respectively, (P > 0.05), except for a higher major bleeding rate in the On-OAC group (P = 0.002). Patients at high risk for stroke (men and women with scores ≥3 and ≥ 4) had better non-thromboembolic and non-MACE results (Both log-rank P < 0.05). Conclusion: Men with a CHA2DS2-VASc score of 2 and women with a score of 3 had a relatively low incidence of stroke events after successful catheter ablation for AF and may be safe for anticoagulation cessation. Greater benefits from long-term OAC were observed in men with CHA2DS2-VASc score ≥3 and women with score ≥4.

Prognostic Impact of Left Atrial Appendage Patency After Device Closure.

BACKGROUND: The prognostic impact of left atrial appendage (LAA) patency, including those with and without visible peri-device leak (PDL), post-LAA closure in patients with atrial fibrillation, remains elusive. METHODS: Patients with atrial fibrillation implanted with the WATCHMAN 2.5 device were prospectively enrolled. The device surveillance by cardiac computed tomography angiography was performed at 3 months post-procedure. Adverse events, including stroke/transient ischemic attack (TIA), major bleeding, cardiovascular death, all-cause death, and the combined major adverse events (MAEs), were compared between patients with complete closure and LAA patency. RESULTS: Among 519 patients with cardiac computed tomography angiography surveillance at 3 months post-LAA closure, 271 (52.2%) showed complete closure, and LAA patency was detected in 248 (47.8%) patients, including 196 (37.8%) with visible PDL and 52 (10.0%) without visible PDL. During a median of 1193 (787-1543) days follow-up, the presence of LAA patency was associated with increased risks of stroke/TIA (adjusted hazard ratio for baseline differences, 3.22 [95% CI, 1.17-8.83]; P=0.023) and MAEs (adjusted hazard ratio, 1.12 [95% CI, 1.06-1.17]; P=0.003). Specifically, LAA patency with visible PDL was associated with increased risks of stroke/TIA (hazard ratio, 3.66 [95% CI, 1.29-10.42]; P=0.015) and MAEs (hazard ratio, 3.71 [95% CI, 1.71-8.07]; P=0.001), although LAA patency without visible PDL showed higher risks of MAEs (hazard ratio, 3.59 [95% CI, 1.28-10.09]; P=0.015). Incidences of stroke/TIA (2.8% versus 3.0% versus 6.7% versus 22.2%; P=0.010), cardiovascular death (0.9% versus 0% versus 1.7% versus 11.1%; P=0.005), and MAEs (4.6% versus 9.0% versus 11.7% versus 22.2%; P=0.017) increased with larger PDL (0, >0 to ≤3, >3 to ≤5, or >5 mm). Older age and discontinuing antiplatelet therapy at 6 months were independent predictors of stroke/TIA and MAEs in patients with LAA patency. CONCLUSIONS: LAA patency detected by cardiac computed tomography angiography at 3 months post-LAA closure is associated with unfavorable prognosis in patients with atrial fibrillation implanted with WATCHMAN 2.5 device. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03788941.

Incidence, impact and predictors of residual device patency after left atrial appendage closure with the LACbes device.

BACKGROUND: The residual device patency (RDP) after left atrial appendage closure (LAAC) with the LACbes device has not been specifically explored in atrial fibrillation (AF) patients. This study aims to explore the incidence, impact and predictors of RDP detected by cardiac computed tomography angiography (CCTA) post LAAC. METHODS: AF patients implanted with the LACbes device were prospectively enrolled. CCTA device surveillance was performed at 3 months post-procedure. Major adverse events (MAEs), including stroke/transient ischemic attack, major bleeding and all-cause death, were evaluated. RESULTS: Among 141 patients with CCTA surveillance, 56 (39.7%) showed no visible leak and 85 (60.3%) showed RDP. During the median follow-up of 443 [232, 706] days, the presence of RDP was not associated with an increased risk of MAEs (adjusted hazard ratio [HR]: 4.07, 95% confidence interval [CI]: 0.49-34.24, p = 0.196), while peri-device leak (PDL) at the lobe was associated with heightened risks of MAEs (adjusted HR: 6.85, 95% CI: 1.62-28.89, p = 0.009). In patients with PDL at the lobe, antiplatelet after 6 months (HR: 0.20, 95% CI: 0.05-0.91, p = 0.038) was independent protective predictor of MAEs. Besides, current smoking (odds ratio [OR]: 7.52, 95% CI: 2.68-21.08, p < 0.001) and maximum diameter of LAA orifice (OR: 1.16, 95% CI: 1.00-1.34, p = 0.048) were independent predictors of PDL at the lobe. CONCLUSIONS: Presence of PDL at the device lobe detected by CCTA at 3-month post LAAC with LACbes is associated with unfavorable prognosis in AF patients. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03788941.

Combined Radiofrequency Ablation and Left Atrial Appendage Closure in Atrial Fibrillation and Systolic Heart Failure.

BACKGROUND: Managing patients with atrial fibrillation (AF) and comorbid heart failure (HF) with reduced (HFrEF) or mildly reduced ejection fraction (HFmrEF) is of clinical importance but a great challenge. This study aimed to evaluate the clinical benefit of the combined radiofrequency catheter ablation (RFCA) and left atrial appendage closure (LAAC) procedure in AF patients complicated with systolic HF. METHODS: AF patients with HFrEF or HFmrEF who underwent the combined RFCA and LAAC procedure were prospectively enrolled in the LAACablation registry. The procedural complications and long-term outcomes were evaluated. Another cohort of AF patients with systolic HF who did not undergo either RFCA or LAAC were used for prognosis comparison. RESULTS: Among 802 AF patients who underwent the combined procedure, 65 patients were comorbid with systolic HF (25 with HFrEF and 40 with HFmrEF). The overall procedural complication rate was 9.2%, which was mainly attributed to acute decompensated HF (6.2%). Accompanied with markedly reduced AF burden (from median [25th, 75th percentile]: 100 [100, 100] to 0 [0, 1.2]%, p < 0.001), upward trajectories of cardiac function were observed in 51 (78.4%) patients, showing improvement in New York Heart Classification (p < 0.01), natriuretic peptide levels (from 1492 [809, 3259] to 413 [163, 880] pg/mL, p < 0.001) and left ventricular EF (from 42.6 ± 5.3 to 53.8 ± 8.2%, p < 0.001). During the 27-month follow-up period, death, thromboembolism, major bleeding, and HF rehospitalization were observed in three, one, one, and four patients, respectively. The observed event rates showed a significant reduction compared with the non-procedure AF-HF cohort (n = 138; for composite endpoint: hazard ratio: 2.509, 95% confidence interval: 1.415-4.449, p = 0.002) and with the respective rates predicted by risk scores. CONCLUSIONS: Combining RFCA and LAAC achieves acceptable safety and credible long-term efficacy in AF patients with systolic HF. Further randomized studies are warranted in a larger patient cohort.

Higher Sodium Channel Excitability in Cardiac Purkinje Fibers: Implications for Multifocal Ectopic Purkinje-Related Premature Contractions.

BACKGROUND: Multifocal ectopic Purkinje-related premature contractions (MEPPCs) are associated with SCN5A variants. However, it is not well understood why Purkinje fibers, but not ventricular myocardium, play a predominant role in arrhythmogenesis. OBJECTIVES: This study sought to explore the underlying mechanisms of MEPPC. METHODS: Whole-cell patch-clamp and molecular biology techniques were used in the present study. RESULTS: Clinical data from one patient with R814W variant showed MEPPC syndrome, which is well responsive to amiodarone. Compared with canine ventricular myocytes, Purkinje cells (PCs) had significantly larger sodium current (INa), leftward shift of INa activation and inactivation curves, suggesting higher sodium channel excitability in PCs. Real-time polymerase chain reaction and Western blot analysis showed that the mRNA and protein expression of NaVß1 and NaVß3 was higher in canine Purkinje fibers than in ventricular myocardium. INa in heterologous Chinese hamster ovary cell expression system co-expressing NaV1.5 and NaVß1/NaVß3 exhibited similar biophysical properties of INa in PCs. R814W variant shifted INa activation in a hyperdepolarized direction, caused a larger window current, and generated an outward-gating pore current at depolarized voltages. Coexpression of NaVß1/NaVß3 with Nav1.5-R814W further left-shifted INa activation and caused an even larger window current and gating pore current, suggesting higher susceptibility of Purkinje fibers to R814W variant. Amiodarone inhibited INa, shifted its inactivation to more negative voltages, and significantly decreased the window current. CONCLUSIONS: A higher expression of ß1 and ß3 subunits contributes to higher sodium channel excitability in cardiac Purkinje fibers, making them more susceptible to MEPPC.

Efficacy of Left Atrial Appendage Closure and Oral Anticoagulation After Atrial Fibrillation Catheter Ablation.

Left atrial appendage closure (LAAC) proved to be noninferior to oral anticoagulation (OAC) in nonablated patients with atrial fibrillation (AF). This study aimed to compare the efficacy and safety of LAAC with those of OAC therapy in patients after AF ablation. This study included patients who underwent catheter ablation (CA) of AF between January 2016 and December 2020. The cohort was divided into CA + LAAC and CA + OAC, where propensity score matching was used to select controls, and each group contained 682 subjects. The enrolled patients' mean age was 70.34 ± 8.32 years, and 47.3% were female; their CHA2DS2-VASc score was 3.48 ± 1.17. Baseline characteristics were similar between groups. After a 3-year mean follow-up, the incidence of thromboembolic events was 1.25 and 1.10 and that of major bleeding events was 0.65 and 1.72 per 100 patient-years in the CA + LAAC, and CA + OAC groups, respectively. The rate of thromboembolisms and major adverse cardiovascular events was similar between the 2 groups (hazard ratio [HR] 1.162, 95% confidence interval [CI] 0.665 to 2.030, p = 0.598, HR 0.711, 95% CI 0.502 to 1.005, p = 0.053); however, that of major bleeding and all-cause death was significantly reduced with LAAC (HR 0.401, 95% CI 0.216 to 0.746, p = 0.004, HR 0.528, 95% CI 0.281 to 0.989, p = 0.046). There was no significant difference in periprocedural complications (p >0.05) and the rate of AF recurrence (OAC vs LAAC: 39.44% vs 40.62%, p = 0.658). LAAC is a reasonable and safer alternative to OAC therapy in high-risk patients after AF ablation.

Safety and efficacy of ablation for atrial fibrillation in combination with left atrial appendage occlusion in octogenarians.

BACKGROUND: Catheter ablation (CA) combined with left atrial appendage occlusion (LAAO) is a feasible approach for atrial fibrillation (AF) patients. Its role in octogenarians with AF is unclear. HYPOTHESIS: In AF patients over 80 years, CA combined with LAAO is a feasible way in restoring sinus rhythm and preventing stroke. METHODS: This is a single-center retrospective study. Patients who underwent CA and LAAO in a single procedure between March 2018 and December 2020 were included. Efficacy endpoints included procedural success rate, AF recurrence rate, and thromboembolic events. Safety endpoints included pericardial effusion/cardiac tamponade, device-related thrombus (DRT), all-cause death, and major bleeding. RESULTS: Five hundred and five patients (mean age 69.5 ± 7.7 years; 230 [45.5%] female) were included, with 46 (9.1%) patients aged ≥80 years old (octogenarian group). Prevalence of paroxysmal AF (25 [54.3%] vs. 207 [45.1%], p < 0.001) and CHA2DS2VASc score (4.1 ± 1.3 vs. 3.1 ± 1.4, p < 0.0001) were higher in octogenarian patients. There were six cases (1.2%) of pericardial effusion (all in nonoctogenarian patients). At 3 months postprocedure, 437 patients underwent TEE/CT. Thirty-two (80%) octogenarian patients and 308 (77.6%) nonoctogenarian patients had no peri-device leak. After a mean follow-up of 26.9 ± 9.1 months, AF was documented in 10 (21.7%) patients in octogenarian group and in 103 (22.4%) patients in nonoctogenarian group (p = 0.99). The annual thromboembolic risk was 2.1% and 0.8% in the octogenarian group and nonoctogenarian group, respectively. Death occurred in 16 nonoctogenarian patients. One major bleeding was recorded in the octogenarian group. CONCLUSIONS: The combination of CA and LAAO in a single procedure is a feasible treatment option in octogenarians with comparable efficacy and safety profile.

Sex Differences in the Combined Ablation and Left Atrial Appendage Closure: Results From LAACablation Registry.

Background: More than 40% of left atrial appendage closure (LAAC) procedures were combined with atrial fibrillation (AF) ablation in China. Objectives: This study aimed to assess the sex differences in the combined radiofrequency catheter ablation and LAAC procedures. Methods: Data from the LAACablation (Left Atrial Appendage Closure in Combination With Catheter Ablation) registry, which enrolled AF patients who underwent the combined procedure between 2018 and 2021, were analyzed. Procedural complications, long-term outcomes, and quality of life (QoL) were compared between sexes. Results: Of 931 patients, 402 (43.2%) were women. Compared with men, women were older (age 71.3 ± 7.4 years vs 68.7 ± 8.1 years; P < 0.001), presented more often with paroxysmal AF (52.5% vs 42.7%; P < 0.003), and had higher CHA2DS2-VASc scores (4.1 ± 1.5 vs 3.1 ± 1.5; P < 0.001), but received less often linear ablation and had shorter total procedural times and radiofrequency catheter ablation times. Women had similar rates of total and major procedural complications but presented with a higher incidence of minor complications than men (3.7% vs 1.3%; P = 0.027). Follow-up over 1,812 patient-years revealed similar adverse events between women and men, including all-cause death (HR: 0.89; 95% CI: 0.43-1.85; P = 0.754), thromboembolic events (HR: 1.17; 95% CI: 0.54-2.52; P = 0.697), major bleeding (HR: 0.96; 95% CI: 0.38-2.44; P = 0.935), and their composite (HR: 0.85; 95% CI: 0.56-1.28; P = 0.434). The recurrence rates of atrial tachyarrhythmia were also comparable between sexes presenting either paroxysmal or persistent AF. Women were seen with greater QoL impairment at baseline, but the sex gap narrowed at 1-year follow-up. Conclusions: In AF patients who underwent the combined procedure, women had similar procedural safety and long-term efficacy to men and presented greater QoL improvement. (Left Atrial Appendage Closure in Combination With Catheter Ablation [LAACablation]; NCT03788941).

Left atrial appendage closure in patients with reversed chicken-wing morphology: Anatomical features and procedural strategy.

Background: Left atrial appendage (LAA) closure (LAAC) in atrial fibrillation (AF) patients with the reversed chicken-wing (RCW) LAA is challenging. Aims: To elucidate the LAAC strategy of the RCW-LAA. Methods: A total of 802 AF patients who were enrolled in the LAACablation registry for LAAC procedure were included, 55 of whom presented with the RCW-LAA. The WATCHMAN device was implanted using the standard protocol when the sheath depth was no less than the device depth (the simple group). For those with a sheath depth of less than the device depth (the complex group), device deployment was attempted with acceptable protrusion or after a repeated atrial transseptal puncture (re-ATP) at a more inferior and anterior position. The anatomical and procedural features were compared between groups and before and after the re-ATP. Results: The success rate of LAAC was significantly lower in patients with the RCW-LAA than with the other morphologies (92.7% vs. 98.8%, p = 0.001). Compared with the simple group, the complex group had shorter root depth and shorter neck length, and more LAAs in the complex group were at lower position (all p < 0.05). The sheath depth after the re-ATP was significantly greater than that before the re-ATP (18.8 ± 3.4 mm vs. 14.7 ± 2.6 mm, p < 0.001). For the patients who underwent re-ATP, the sheath went significantly deeper in successful procedures than in aborted procedures (19.7 ± 3.3 mm vs. 15.8 ± 1.8 mm, p = 0.040). Conclusions: The anatomical features of the RCW-LAA were related to the complexity of the LAAC procedure. The re-ATP at an inferior and anterior location could increase the success rate of LAAC. ClinicalTrialsgov: NCT03788941.

Novel dual-reference approach facilitates the activation mapping and catheter ablation of premature atrial complexes with non-pulmonary vein and non-superior vena cava origins.

AIMS: Activation mapping of premature atrial complexes (PACs) proves challenging due to interference by mechanical bumping and non-targeted ectopies. This study aims to compare the mapping efficacy, instant success, and long-term recurrence of catheter ablation for PACs with non-pulmonary vein (PV) and non-superior vena cava (SVC) origins between the novel dual-reference approach (DRA) and the routine single-reference approach (SRA) of mapping. METHODS AND RESULTS: Patients with symptomatic, drug-refractory PACs, or frequent residual PACs after atrial tachyarrhythmia ablation were enrolled. During activation mapping, the coronary sinus (CS) catheter was used as the only timing reference in the SRA group. In the DRA group, another catheter, which was spatially separated from the CS catheter, was used as the second reference. The timing difference between the two references was used to discriminate the targeted PACs from the uninterested rhythms. Procedural parameters and long-term recurrence were compared. A total of 188 patients (109 in SRA and 79 in DRA) were enrolled. The baseline characteristics were similar. Compared with the SRA group, the DRA group had less repeated mapping (1.2 ± 0.4 vs. 1.4 ± 0.5, P = 0.004), shorter mapping (15 ± 6 vs. 23 ± 7 min, P < 0.001) and procedural time (119 ± 28 vs. 132 ± 22 min, P = 0.001), similar procedural complication rates (3.6 vs. 3.8%, P > 0.999), higher instant success (96.2 vs. 87.2%, P = 0.039), and lower recurrence rate (15.2 vs. 29.3%, hazard ratio 1.943, P = 0.033) during a 24-month follow-up. CONCLUSION: As a novel strategy, the DRA shortens the procedural time and improves both instant and long-term success of PAC ablation, serving as a promising approach in mapping PACs with non-PV and non-SVC origins.

Case report: Intrapericardial thrombus aspiration in early stage of pericardial thrombosis for cardiac tamponade complicating percutaneous left atrial appendage closure.

Introduction: Pericardial thrombosis that complicates pericardial bleeding is a life-threatening emergency in interventional cardiology, and surgery remains the only definitive treatment option. We report the first case of successful intrapericardial thrombus aspiration using a dedicated thrombus aspiration catheter in the early stage of pericardial thrombosis. Case report: A 76-year-old woman with non-valve atrial fibrillation underwent percutaneous left atrial appendage (LAA) closure for secondary prevention of stroke. A 24-mm Watchman device was deployed under fluoroscopic guidance. Post-deployment angiography revealed LAA perforation, which led to the rapid onset of cardiac tamponade. Emergency pericardiocentesis was performed and the deep-seated device was redeployed at a more proximal position to seal the distal perforation. Pericardial bleeding was controlled after the drainage of 400 ml of blood. However, the patient re-developed cardiac tamponade following a period of stability. The patient was diagnosed with early-stage pericardial thrombosis based on echocardiographic findings of a hypoechoic effusion in the pericardial space. Thrombus aspiration using a pigtail catheter and long sheath failed; however, we performed successful intrapericardial thrombus aspiration using a dedicated thrombus aspiration catheter. We drained 120 ml of sludge-like blood, and the patient underwent successful conservative management without surgical intervention. Conclusion: This case report highlights the potential usefulness of a percutaneous intrapericardial thrombus aspiration technique using a dedicated thrombus aspiration catheter in selected patients with early-stage pericardial thrombosis, as a less invasive alternative to cardiac surgery.

Long-term outcome of combined catheter ablation and left atrial appendage closure in atrial fibrillation patients.

BACKGROUND: The combined procedure of catheter ablation and left atrial appendage closure (LAAC) aims to simultaneously control the heart rhythm and reduce the risk of strokes in patients with atrial fibrillation (AF). The study aims to evaluate the procedural safety and long-term outcome of the combined procedure in a large patient cohort. METHODS: Clinical data of AF patients who underwent the combined procedure was retrospectively analyzed. Procedural and imaging follow-up parameters were compared between the transesophageal echocardiography-guided standard process and fluoroscopy-guided modified process, and between the single-seal WATCHMAN and dual-seal LACBES devices. Long-term outcomes included all-cause mortality, thromboembolic events, major bleeding, and recurrence of atrial tachyarrhythmias. RESULTS: A total of 1114 patients were included. The rates of procedure-related major complications were comparable between the standard and modified processes (3.7% vs. 2.2%, p = 0.219), except for a higher incidence of respiratory depression in standard process group (0.9% vs 0%, p = 0.037), and between WATCHMAN and LACBES devices (2.4% vs. 3.3%, p = 0.535). The follow-up imaging evaluation revealed a high rate of satisfactory seals (99.7%) and a low rate of device related thrombus (1.9%), which were similar between two process groups and devices. The follow-up of over 1960 patient-years revealed low rates of mortality, thromboembolism, and nonprocedural major bleeding (1.8, 3.2, and 0.9 per 100 patient-years, respectively). Recurrent atrial tachyarrhythmias was observed in 23.9% patients. CONCLUSIONS: The results supported the safety and long-term efficacy of the combined procedure of catheter ablation and LAAC. Fluoroscopy-guided LAAC device implantation may be considered in experienced centers.

Mysterious window: A right coronary artery-left ventricular fistula diagnosed by multiple imaging approaches.

Prevalence of primary coronary cameral fistula (CCF) is extremely rare, especially for CCF with its drainage channel into the left ventricle (LV). We describe a 45-year-old male patient with giant aneurysm associated with proximal right coronary artery (RCA), and the distal end of RCA draining into the LV through a fistula, which was discovered by echocardiography. Dual-source computer tomography revealed only the CCF-related giant RCA aneurysm. The drainage site of the fistula and the above coexistent abnormality could not be visualized clearly by coronary artery angiography because of deficient contrast medium filling into the aneurysm. The patient underwent surgical resection of the giant aneurysm and occlusion of the fistula in 2015. Finally, the patient accepted another operation to occlude the residual coronary fistula in 2021.

Left Atrial Appendage Closure for Primary and Secondary Stroke Prevention in Patients With Hypertrophic Cardiomyopathy and Atrial Fibrillation: A Pilot Study.

Background: The aim of this study was to investigate the efficacy of left atrial appendage closure (LAAC) for primary and secondary stroke prevention in patients with hypertrophic cardiomyopathy (HCM) and atrial fibrillation (AF). Methods: This pilot study enrolled 36 patients with HCM and AF who underwent LAAC between April 2017 and December 2019, of whom 22 were for primary stroke prevention and 14 were for secondary prevention. Results: The patients enrolled in this study had non-obstructive (86.1%) or mild obstructive (13.9%) HCM. Patients in the Secondary Prevention Group had higher CHA2DS2-VASc scores (5.1 ± 1.4 vs. 2.6 ± 1.6, P < 0.001) and higher HAS-BLED scores (2.8 ± 1.0 vs. 1.5 ± 0.9, P < 0.001) compared with those in the Primary Prevention Group. Successful closure with satisfactory seals (residual leak ≤ 5 mm) was achieved in all patients, with complete occlusion in 86.4% of the Primary Prevention Group and 92.9% of the Secondary Prevention Group. Procedural-related complications included one pericardial effusion and one groin hematoma. One device-related thrombus was identified in the Secondary Prevention Group and resolved after anticoagulation. During a mean follow-up time of 28.4 months, one bleeding event was recorded. There were no thromboembolic events or deaths in either group, with 97.2% of the patients achieving freedom from anticoagulation therapy. Conclusions: Initial results suggest that LAAC can be a safe and feasible alternative for primary and secondary stroke prevention in selected patients with HCM and AF. Further studies with larger samples are required.

Value of detecting peri-device leak and incomplete endothelialization by cardiac CT angiography in atrial fibrillation patients post Watchman LAAC combined with radiofrequency ablation.

OBJECTIVES: To explore the value of detecting the peri-device leak (PDL) and device endothelialization after left atrial appendage closure (LAAC) by cardiac computed tomography (CT) in patients with atrial fibrillation (AF), who underwent Watchman LAAC combined with radiofrequency ablation of atrial fibrillation (AFCA). METHODS: Patients with symptomatic drug-refractory atrial fibrillation at high risk of stroke (CHA2 DS2 -VASc Score ≥ 2), who underwent Watchman LAAC combined with AFCA in our center from March 2017 to December 2018 were enrolled. Maximum diameter of LAA orifice was determined by preoperative CCTA. A standardized view of Watchman device was obtained by postoperative CCTA multiplannar reconstruction to evaluate the PDL and device endothelialization. RESULTS: Approximately 84 patients post successful LAAC and AFCA were enrolled in this study. The satisfactory LAA occlusion rate was 100%. There was no death, bleeding, stroke, and device-related thrombus (DRT) events. At 6-month postprocedure, CCTA images evidenced complete endothelialization in 44 patients (no contrast enhancement in LAA); contrast enhancement in LAA and visible PDL in 33 patients; contrast enhancement in LAA but without PDL in seven patients (incomplete device endothelialization). Maximum diameter of LAA orifice could independently predict the occurrence of PDL (odds ratio, 1.31; 95% confidence interval, 1.11-1.55; p = .002), sensitivity was 69.7% and specificity was 80.4% with the cutoff value of maximum diameter of LAA orifice more than 28.2 mm on predicting PDL. CONCLUSIONS: CCTA is feasible to evaluate PDL and device endothelialization after LAAC. The maximum diameter of LAA orifice derived from CT can independently predict the occurrence of post-LAAC PDL.

Cadherin-11 Deficiency Attenuates Ang-II-Induced Atrial Fibrosis and Susceptibility to Atrial Fibrillation.

BACKGROUND: Atrial fibrosis serves as a disease initiating mechanism in the development of atrial fibrillation. Angiotensin II (Ang-II), a key mediator for atrial fibrosis, aberrantly activates atrial fibroblasts (AFs) into myofibroblasts, resulting in subsequent excessive synthesis and deposition of extracellular matrix (ECM). Cadherin-11 (CDH11) is essential in the development of non-cardiac fibrotic diseases. In this study, we investigated its role in the pathogenesis and underlying mechanism of atrial fibrillation. METHODS: We obtained left atrial tissues from either patients with atrial fibrillation or Ang-II-induced atrial fibrosis mice. We utilized a global CDH11 knockout mouse (CDH11-/-) model to determine the effect of CDH11 on AF cell proliferation, migration, ECM synthesis/deposition. RNA-Seq of isolated AFs from CDH11-/- or normal mice was performed and differential expressed genes were analyzed. The mouse susceptibility to atrial fibrillation was examined by cardiac electrophysiology. RESULTS: We found that cadherin-11 was significantly up-regulated in fibrotic atrial tissue from patients with atrial fibrillation and Ang-II-induced mice. Both normal and CDH11-/- mice did not develop atrial fibrosis at resting state. However, after Ang-II infusion, unlike severe atrial fibrosis occurred in normal mice, CDH11-/- mice displayed a reduced atrial fibrosis. Atrial fibroblasts with CDH11 deletion from CDH11-/- mice showed reduction in Ang-II-induced cell proliferation, migration and ECM synthesis/deposition, indicating the involvement of CDH11 in atrial fibrosis. Consistently, RNA-Seq of CDH11-null AFs uncovered significant decrease in pro-fibrotic gene expression. In addition, we identified reduction of transcripts associated with Smad2/3, ERK1/2 and JNK pathways. Further, CDH11-/- mice showed a significantly attenuated Ang-II-induced susceptibility to atrial fibrillation. CONCLUSION: Our results indicate that CDH11 potentiates Ang-II-induced activation of AFs. The pathogenesis of atrial fibrosis is through CDH11 mediated stimulation of Smad2/3, ERK1/2 and JNK pathways. Thus, CDH11 might serve as a novel therapeutic target for ameliorating the development of atrial fibrillation.

EZH2 as an Epigenetic Regulator of Cardiovascular Development and Diseases.

ABSTRACT: Enhancer of zeste homolog 2(EZH2) is an enzymatic subunit of polycomb repressive complex 2 (PRC2) and is responsible for catalyzing mono-, di-, and trimethylation of histone H3 at lysine-27(H3K27me1/2/3). Many noncoding RNAs or signaling pathways are involved in EZH2 functional alterations. This new epigenetic regulation of target genes is able to silence downstream gene expression and modify physiological and pathological processes in heart development, cardiomyocyte regeneration, and cardiovascular diseases, such as hypertrophy, ischemic heart diseases, atherosclerosis, and cardiac fibrosis. Targeting the function of EZH2 could be a potential therapeutic approach for cardiovascular diseases.

Image fusion of integrating fluoroscopy into 3D computed tomography in guidance of left atrial appendage closure.

AIMS: We evaluated the feasibility of left atrial appendage (LAA) closure guided by the image fusion of integrating fluoroscopy into 3D computed tomography (CT). METHODS AND RESULTS: A total of 117 consecutive patients who underwent LAA closure with or without the image fusion were matched (1:2). Each LAA closure step of the Image fusion group was guided by the preprocedure CT and image fusion, especially in the plan of LAA measurement and transseptal puncture. All patients were successfully implanted with a WATCHMAN closure device. Comparing the two groups, the mean number of recapture times and the number of devices per patient of the Image fusion group were significantly lower (0.4 ± 0.5 vs. 0.7 ± 0.8, P = 0.031 and 1.0 ± 0.2 vs. 1.1 ± 0.3, P = 0.027, respectively). The one-time successful deployment rate by the support of the image fusion was higher than in the control group (66.7% vs. 44.9%, P = 0.026). Each case of the Image fusion group was completely occluded with one transseptal puncture, while five of the Non-image fusion group required redo transseptal punctures. During the 45-day follow-up, both group cases presented occlusion efficiency and no major adverse cardiac events were observed. CONCLUSION: Image fusion technique integrating fluoroscopy into the 3D CT is safe and feasible which can be easily incorporated into the procedural work-flow of percutaneous LAA closure. The fusion image can play an important alternative role in the plan of LAA measurement and transseptal puncture site for improving the LAA closure procedure.

Combined Therapy of Catheter Ablation and Left Atrial Appendage Closure for Patients with Atrial Fibrillation: A Case-Control Study.

AIM: The feasibility and safety of performing the combined procedure of catheter ablation (CA) and left atrial appendage closure (LAAC) for atrial fibrillation (AF) have been reported by observational studies without controls. The aim of this study was to compare the procedural and long-term outcomes of combined procedures with isolated CA or LAAC. METHODS AND RESULTS: This study included patients who underwent combined CA and LAAC (combined group), CA alone (CA-only group), or LAAC alone (LAAC-only group). Propensity score matching was used to select controls from the CA-only and LAAC-only groups. Each group contained 76 subjects. The procedures were successfully performed in all the patients. Procedure-related complications of the combined group included one pericardial effusion and two groin haematomas, which did not differ significantly with those of the CA-only group (3.9% vs. 2.6%, P=0.650) or the LAAC-only group (3.9% vs. 2.6%, P=0.650), respectively. The AF-free rate of the combined group was comparable with that of the CA-only group after a mean of 2 years follow-up (67.1% vs. 69.7%, P=0.727). Compared with the LAAC-only group, the combined group achieved similar complete occlusion rate at implant (94.7% vs. 93.4%) and at 45 days (82.9% vs. 85.5%). At the end of follow-up, ischemic stroke and bleeding events of the combined group were low (3.9%) and were comparable with those of the CA-only group (5.3%) and the LAAC-only group (2.6%). CONCLUSIONS: The combination of AF-CA and LAAC is safe and efficacious compared with single procedures alone.