Prevalence, characteristics, and predictors of endocardial and nonendocardial conduction gaps during local impedance-guided extensive pulmonary vein isolation of atrial fibrillation with high-resolution mapping.

INTRODUCTION: Local impedance (LI) drops during radiofrequency ablation can predict lesion formation. Some conduction gaps during pulmonary vein isolation (PVI) can be associated with nonendocardial connections. This study aimed to investigate the incidence, characteristics, and predictors of endocardial and nonendocardial conduction gaps during an LI-guided PVI. METHODS AND RESULTS: We prospectively enrolled 157 consecutive patients undergoing an initial LI-guided extensive PVI of atrial fibrillation (AF). After the first-pass encirclement, the residual conduction gaps and reconnected gaps were mapped using Rhythmia (Boston Scientific) and a mini-basket catheter. Right and left PV (RPV/LPV) gaps were observed in 22.3% and 18.5% of the patients, respectively: 27 endocardial and 49 nonendocardial gaps. The carina regions were common sites for the gaps (51 carina-related vs. 25 noncarina-related). The carina-related gaps consisted of more nonendocardial gaps than endocardial gaps (RPVs: 90.0% vs. 10.0%, p = .001; LPVs: 76.2% vs. 23.8%, p < .001). A univariate analysis revealed that paroxysmal AF and the left atrial (LA) volume index for RPV endocardial gaps (odds ratio [OR]: 8.640 and 0.946; p = .043 and 0.009), minor right inferior PV diameter for RPV nonendocardial gaps (OR: 1.165; p = .028), and major left inferior PV diameter for LPV endocardial gaps (OR: 1.233; p = .028) were significant predictors. CONCLUSIONS: During the LI-guided PVI, approximately two-thirds of the conduction gaps were nonendocardial. The carina regions had more conduction gaps than noncarina regions, which was due to the presence of nonendocardial connections. Paroxysmal AF, a lower LA volume index, and larger inferior PV diameters may increase the risk of conduction gaps.

Incidence and characteristics of silent cerebral embolisms after radiofrequency-based atrial fibrillation ablation: A propensity score-matched analysis between different mapping catheters and indices for guiding ablation.

INTRODUCTION: The difference in the incidence and characteristics of silent cerebral events (SCEs) after radiofrequency-based atrial fibrillation (AF) ablation between the different mapping catheters and indices used for guiding radiofrequency ablation remains unclear. This study aimed to compare the incidence and characteristics of postablation SCEs between the following two groups: Group C, Ablation Index-guided ablation using two circular mapping catheters with CARTO (Biosense Webster); Group R, local impedance-guided ablation using one mini-basket catheter and one circular mapping with Rhythmia (Boston Scientific). METHODS AND RESULTS: Of 211 consecutive patients who underwent an AF ablation and brain magnetic resonance (MR) imaging after the ablation, 120 patients (each group, n = 60) were selected by propensity score matching. SCEs were detected in 37 patients (30.8%). Group R had a higher incidence of SCEs (51.7% vs. 10.0%; p < .001) and more SCEs per patient (median, 3 vs. 1, p = .028) than Group C. A multivariate analysis demonstrated that nonparoxysmal AF and being Group R were independent positive predictors of SCEs (odds ratios, 6.930 and 15.464; both p < .001). On the follow-up MR imaging, all SCEs in Group C and 87.9% of the SCEs in Group R disappeared (p = .537). CONCLUSIONS: Group R had a significantly higher incidence of SCEs than Group C. Most probably the use of a complexly designed basket mapping catheter is the reason for the difference in the incidence of SCEs but further validation is needed. A nonparoxysmal form of AF may also increase the risk of SCEs during these ablation procedures.

The effect of bilateral cardiac sympathetic denervation for refractory ventricular tachycardia in ischemic cardiomyopathy.

Recent studies have shown that cardiac sympathetic denervation (CSD) is effective in the treatment of refractory ventricular tachyarrhythmia in patients with structural heart disease. This case report aimed to highlight the effect of bilateral CSD in suppressing treatment-resistant ventricular tachycardia in patients with ischemic cardiomyopathy.

Impact of the type of electroanatomic mapping system on the incidence of cerebral embolism after radiofrequency catheter ablation of left atrial tachycardias.

BACKGROUND: Left atrial tachycardias (ATs) often occur after left atrial ablation. The incidence of symptomatic and silent cerebral embolism after radiofrequency catheter ablation of left ATs and the impact of the type of 3-dimensional electroanatomic mapping (3D-EAM) system on the incidence of cerebral embolism remain unclear. OBJECTIVES: This study aimed to investigate the incidence of cerebral embolism after a 3D-EAM system-guided left AT ablation procedure and compare that between the different 3D-EAM systems. METHODS: We prospectively enrolled 59 patients who underwent left AT ablation and brain magnetic resonance imaging after the procedure: 30 were guided by the Rhythmia system (Boston Scientific, Marlborough, MA) and 29 by the CARTO system (Biosense Webster, Diamond Bar, CA) (groups R and C, respectively). RESULTS: One transient ischemic attack occurred in group R, and no symptomatic embolism occurred in group C. Silent cerebral ischemic lesions (SCILs) were observed in 35 patients (59.3%), and group R had a significantly higher incidence of SCILs than did group C (86.2% vs 33.3%; P < .001). In multivariate analysis, group R and left atrial linear ablation were independent positive predictors of SCILs (odds ratio 12.822 and 8.668; P = .001 and P = .005). The incidence of bleeding complications was comparable between groups R and C (0% vs 3.3%; P = .508). CONCLUSION: Group R exhibited a higher incidence of postablation cerebral embolism than did group C. The use of the high-resolution 3D-EAM system with a mini-basket catheter to guide radiofrequency ablation of left atrial macroreentrant tachycardias may markedly increase the risk of silent cerebral embolism. The present results require further validation in a randomized study.

Uninterrupted vs. interrupted periprocedural direct oral anticoagulants for catheter ablation of atrial fibrillation: a prospective randomized single-centre study on post-ablation thrombo-embolic and haemorrhagic events.

AIMS: This prospective, randomized, single-centre study aimed to directly compare the safety and efficacy of uninterrupted and interrupted periprocedural anticoagulation protocols with direct oral anticoagulants (DOACs) in patients undergoing catheter ablation of non-valvular atrial fibrillation (NVAF). METHODS AND RESULTS: We randomly assigned 846 NVAF patients receiving DOACs prior to ablation to uninterruption (n = 422) or interruption (n = 424) of the DOACs on the day of the procedure. The primary endpoint was a composite of symptomatic thromboembolisms and major bleeding events within 30 days after the ablation. Secondary endpoints included symptomatic and silent thromboembolisms and major and minor bleeding events. The primary endpoint occurred in 0.7% of the uninterrupted DOAC group [1 transient ischaemic attack (TIA) and 2 major bleeding events] and 1.2% of the interrupted DOAC group (1 TIA and 4 major bleeding events) (P = 0.480). The incidence of major and minor bleeding was comparable between the two groups (0.5% vs. 0.9%, P = 0.345; 5.9% vs. 5.4%, P = 0.753). Silent cerebral ischaemic lesions (SCILs) were observed in 138 (20.9%) of the 661 patients undergoing post-ablation magnetic resonance (MR) imaging. The uninterrupted and interrupted DOAC groups revealed a similar incidence of SCILs (19.8% vs. 22.0%, P = 0.484) and percentage of SCILs with disappearance on follow-up MR imaging (77.8% vs. 82.1%, P = 0.428). CONCLUSION: Both the uninterrupted and interrupted DOAC protocols revealed a low risk of symptomatic thromboembolisms and major bleeding events and similar incidence of SCILs and minor bleeding events and may be feasible for periprocedural anticoagulation in NVAF patients undergoing catheter ablation.

Postablation cerebral embolisms in balloon-based atrial fibrillation ablation with periprocedural direct oral anticoagulants: A comparison between cryoballoon and HotBalloon ablation.

INTRODUCTION: This prospective observational study aimed to investigate the incidence of symptomatic and silent cerebral embolisms after balloon-based ablation of atrial fibrillation (AF) in patients receiving periprocedural anticoagulation with direct oral anticoagulants (DOACs), and compare that between cryoballoon and HotBalloon ablation (CBA and HBA). METHODS AND RESULTS: We enrolled 123 consecutive AF patients who underwent a balloon-based pulmonary vein isolation (PVI) and brain magnetic resonance (MR) imaging after the ablation procedure (CBA, n = 65; HBA, n = 58). The DOACs were continued in 62 patients throughout the periprocedural period and discontinued in 61 on the procedural day. Intravenous heparin was infused to maintain an activated clotting time of 300 to 400 seconds during the procedure. No symptomatic embolisms occurred in this series. Silent cerebral ischemic lesions (SCILs) were observed on MR imaging in 22 patients (17.9%), and the incidence of SCILs did not significantly differ between the CBA and HBA groups (21.5 vs 13.8%; P = 0.263). According to a multivariate logistic regression analysis, an older age was an independent positive predictor of SCILs (odds ratio, 1.062; 95% CI, 1.001-1.126; P = 0.046), but neither the balloon catheter type nor periprocedural continuation or discontinuation of the DOACs were significant predictors. The incidence of major and minor bleeding complications was comparable between the CBA and HBA groups (1.5 vs 0%, P = 0.528; 7.7 vs 5.2%, P = 0.424). CONCLUSIONS: Both CBA and HBA of AF revealed a similar incidence of postablation cerebral embolisms. Elderly patients may be at a risk of SCILs after a balloon-based PVI with periprocedural DOAC treatment.

Drug-induced Liver Injury Caused by Ipragliflozin Administration with Causality Established by a Positive Lymphocyte Transformation Test (LTT) and the Roussel Uclaf Causality Assessment Method (RUCAM): A Case Report

ABSTRACT A 75-year old male patient had been regularly visiting our hospital for the management of his type 2 diabetes mellitus since he was diagnosed at age 64 years. When he developed hypoglycemic episodes with sulfonylurea, ipragliflozin (50 mg/day) was started to replace the sulfonylurea therapy. However, 49 days after starting ipragliflozin, his AST increased from 13 to 622 U/L, ALT increased from 9 to 266 U/L, ALP increased from 239 to 752 U/L, and γ-GTP increased from 19 to 176 U/L. ZTT was 3.5 U, TTT was 0.4 U, and total bilirubin was 0.7 mg/dL. IgM hepatitis A antibody, hepatitis B antigen, hepatitis C virus antibody, IgM CMV antibody, and IgM EB VCA antibody were negative, whereas a lymphocyte transformation test for ipragliflozin was positive. Abdominal CT scan showed mild fatty liver but no sign of nodular lesions. Following admission to our hospital, he received liver supportive therapy with the discontinuation of ipragliflozin therapy. He was discharged from the hospital 18 days later with AST and ALT levels reduced to 20 U/L and 13 U/L, respectively. Based on the clinical presentation of this patient, it is highly important to monitor liver function along with other possible clinical complications (e.g., dehydration, ketosis, and urinary tract infection) associated with SGLT2 inhibitor therapy.

Drug-induced Liver injury Caused by Ipragliflozin Administration with Causality Established by a Positive Lymphocyte Transformation Test (LTT) and the Roussel Uclaf Causality Assessment Method (RUCAM): A Case Report.

A 75-year old male patient had been regularly visiting our hospital for the management of his type 2 diabetes mellitus since he was diagnosed at age 64 years. When he developed hypoglycemic episodes with sulfonylurea, ipragliflozin (50 mg/day) was started to replace the sulfonylurea therapy. However, 49 days after starting ipragliflozin, his AST increased from 13 to 622 U/L, ALT increased from 9 to 266 U/L, ALP increased from 239 to 752 U/L, and (Υ-GTP) increased from 19 to 176 U/L. ZTT was 3.5 U, TTT was 0.4 U, and total bilirubin was 0.7 mg/dL. IgM hepatitis A antibody, hepatitis B antigen, hepatitis C virus antibody, IgM CMV antibody, and IgM EB VCA antibody were negative, whereas a lymphocyte transformation test for ipragliflozin was positive. Abdominal CT scan showed mild fatty liver but no sign of nodular lesions. Following admission to our hospital, he received liver supportive therapy with the discontinuation of ipragliflozin therapy. He was discharged from the hospital 18 days later with AST and ALT levels reduced to 20 U/L and 13 U/L, respectively. Based on the clinical presentation of this patient, it is highly important to monitor liver function along with other possible clinical complications (e.g., dehydration, ketosis, and urinary tract infection) associated with SGLT2 inhibitortherapy.

Subcutaneous abdominal adipose tissue is associated with an index of insulin sensitivity/resistance.

To assess whether there is any clinical significance for determining the normal range of subcutaneous abdominal fat area, we compared fat area with insulin sensitivity. Visceral and subcutaneous abdominal fat area the L4-L5 thoracic level was determined by computed tomography (CT). Plasma glucose and insulin levels were determined after an overnight fast and calculated by the homeostatic model assessment of insulin resistance (HOMA-IR). We analyzed 350 (180 male and 170 female) subjects whose BMI was 18.5≤BMI<25. The subcutaneous abdominal fat area of the female subjects was 124.7 ± 46.13 cm2 and that of male subjects was 77.53 ± 37.53 cm2 (mean ± SD). We compared HOMA-IR between subjects whose visceral abdominal fat area was above 100 cm2 and subcutaneous abdominal fat area below the mean + 2SD (15 subjects, 6 male and 9 female) with subjects whose visceral abdominal fat area was also above 100 cm2 but whose subcutaneous abdominal fat area was above the mean + 2SD (20 subjects, 7 male and 13 female). The HOMA-IR of the former subjects group was 8.17+/-6.22 and that of the latter subjects group was 3.37+/-2.07 (p = 0.0486). Subjects with increased subcutaneous abdominal fat area displayed lower HOMA-IR values, demonstrating a protective effect of subcutaneous fat for individuals with visceral fat area above 1002 cm.