Background:Atrial fibrillation (AF) is a common cardiac arrhythmia, associated with increased cardiovascular morbidity and mortality including thromboembolic events. The aims of this study were to ...assess the prevalence of left atrial appendage (LAA) thrombi in Japanese non-valvular atrial fibrillation (NVAF) patients undergoing preprocedural transesophageal echocardiography (TEE) during anticoagulation therapy, and to compare the efficacy of warfarin and direct oral anticoagulants (DOAC).Methods and Results:This retrospective study reviewed records of 559 consecutive NVAF patients (445 men; age, 62±11 years) undergoing preprocedural TEE following at least 3 weeks of anticoagulation therapy. Of these, 275 patients had non-paroxysmal AF (49%). LAA thrombus was observed in 15 patients (2.7%). The prevalence of LAA thrombi was similar between the DOAC group (2.6%) and the warfarin group (2.8%, P=0.86). No patients with CHA2DS2-VASc score=0, or paroxysmal AF without prior stroke or transient ischemic attack, had LAA thrombi. On univariate analysis, non-paroxysmal AF, structural heart disease, antiplatelet therapy, larger left atrium, higher brain natriuretic peptide (BNP), reduced LAA flow, and higher CHA2DS2-VASc score were all associated with LAA thrombi. On multivariate analysis, BNP ≥173 pg/mL remained the only independent predictor of LAA thrombi.Conclusions:LAA thrombi were found in 2.7% of Japanese NVAF patients scheduled for procedures despite ongoing oral anticoagulation therapy. Incidence of thrombi was similar for patients on DOAC and on warfarin.
Background:Recent experimental studies have demonstrated that several microRNAs (miRNAs) expressed in atrial tissue promote a substrate of atrial fibrillation (AF). However, because it has not been ...fully elucidated whether these experimental data contribute to identifying circulating miRNAs as biomarkers for AF, we used a combined analysis of human serum and murine atrial samples with the aim of identifying these biomarkers for predicting AF.Methods and Results:Comprehensive analyses were performed to screen 733 miRNAs in serum from 10 AF patients and 5 controls, and 672 miRNAs in atrial tissue from 6 inducible atrial tachycardia model mice and 3 controls. We selected miRNAs for which expression was detected in both analyses, and their expression levels were changed in the human analyses, the murine analyses, or both. This screening identified 11 candidate miRNAs. Next, we quantified the selected miRNAs using a quantitative RT-PCR in 50 AF and 50 non-AF subjects. The individual assessment revealed that 4 miRNAs (miR-99a-5p, miR-192-5p, miR-214-3p, and miR-342-5p) were significantly upregulated in AF patients. A receiver-operating characteristics curve indicated that miR-214-3p and miR-342-5p had the highest accuracy. The combination of the 4 miRNAs modestly improved the predictive accuracy for AF (76% sensitivity, 80% specificity).Conclusions:Novel circulating miRNAs were upregulated in the serum of AF patients and might be potential biomarkers of AF.
Background:The aim of this study was to categorize the conduction patterns between the right atrium (RA) and the superior vena cava (SVC), and to determine the ideal procedure for SVC isolation using ...a novel high-resolution mapping system.Methods and Results:RA-SVC conduction was evaluated using the RHYTHMIA system in 113 patients (age 62.8±11.5 years, paroxysmal: 67) with atrial fibrillation (AF) after pulmonary vein (PV) isolation. In 56 patients, a line of conduction block was found to run obliquely just above the sinus node (Block group). The remaining 57 patients did not have block (Non-block group). Non-PV foci were spontaneous or provoked with isoproterenol after electrical cardioversion of pacing-induced AF. In 43 patients with SVC foci (Block group: 22, Non-Block group: 21), SVC was isolated by radiofrequency applications delivered along the line connecting the open ends of the block line (Block group) or by conventional methods (Non-block group). The Block group required fewer radiofrequency deliveries for SVC isolation than the Non-Block group (4.2±0.9 vs. 10.2±2.8 times; P<0.0001). The isolated SVC area was larger in the Block group (15.7±3.7 vs. 10.5±3.1 cm2; P<0.0001).Conclusions:We found that approximately half of patients with AF had a diagonal line of block at the RA-SVC junction that could be utilized to isolate the SVC with fewer radiofrequency deliveries.
Few data are available on gastric hypomotility (GH) after cryoballoon pulmonary vein isolation. Also, the use of esophageal temperature monitoring for the prevention of endoscopically detected ...esophageal lesions (EDELs) is not well established.
The purpose of this study was to investigate GH and the impact of an esophageal probe on EDELs during second-generation cryoballoon ablation.
One hundred four patients with paroxysmal atrial fibrillation undergoing second-generation cryoballoon ablation under conscious sedation followed by esophagogastroscopy were prospectively included. Temperature probes were used in the first 40 (38.5%) patients, but not in the latter 64 (61.5%). Pulmonary vein isolation was performed with one 28-mm balloon using single 3-minute freeze techniques.
Clinical and procedural characteristics were similar between the groups. Esophagogastroscopy 1.4 ± 0.5 days postablation demonstrated GH and EDELs in 18 (17.3%) and 9 (8.7%) patients. The incidence of GH was similar (7 of 40 vs 11 of 64; P = .967) between the groups, while that of EDELs was significantly higher in the former than in the latter group (8 of 40 vs 1 of 64; P < .0001). In multivariate analyses, the esophagus-right inferior pulmonary vein ostium distance (hazard ratio 0.870; 95% confidence interval 0.798-0.948; P = .002) was the sole predictor of GH, and the optimal cutoff for the prediction was 18.2 mm (sensitivity 88.1%; specificity 77.8%). The use of esophageal probes was the sole predictor of EDELs (hazard ratio 15.750; 95% confidence interval 1.887-131.471; P = .011). All collateral damage was asymptomatic and healed on repeat esophagogastroscopy at a mean of 2 ± 1 months postprocedure.
Second-generation cryoballoon ablation is associated with an increased incidence of silent periesophageal nerve injury even using short freeze times, and anatomical information aids identifying high-risk populations. The use of esophageal probes increases the risk of EDELs.
Background:Pulmonary vein isolation (PVI) using a cryoballoon (CB) is utilized for treating atrial fibrillation. This study aimed to assess the effect of the procedural characteristics of CB-based ...PVI (CB-PVI) on late PV reconnections.Methods and Results:A total of 389 consecutive patients underwent the CB-PVI as their index procedure; 45 consecutive patients underwent re-do procedures (184±87 days after the index CB-PVI). A total of 146 of 178 PVs (82%) remained isolated. The occlusion grade was evaluated in 171 PVs. Complete PV occlusion by the CB (grade 4) was obtained in 122 of 171 PVs (71%) during the index CB-PVI and the PVI status was maintained in 111 PVs (91%). Among the remaining 49 CB-PVIs without complete PV occlusion (grades 1–3), 20 PVs (41%) had late PV reconnections despite successful PVI during the index CB-PVI. A “pull-down maneuver” was performed in 20 PVs because of leakage of blood at the inferior aspect of the PVs, and all those PVs with a successful pull-down maneuver maintained their PVI status. A multivariate analysis demonstrated that the presence of complete PV occlusion was the only independent predictor for persistence of PVI.Conclusions:The occlusion grade was a reliable predictor of the long-term durability of PVI.
Purpose
Rapid ventricular pacing (RVP) was reported to improve the cooling effects of the cryoballoon (CB). The aim of this study was to investigate the safety and efficacy of RVP for left atrial ...posterior wall isolation (PWI) by the CB.
Methods
One hundred consecutive patients (males 80, mean age 63 ± 10 years) with persistent atrial fibrillation underwent left atrial roof (LA-RB) and bottom block line (LA-BB) creation by CB to achieve PWI. Patients were randomized into two groups according to whether they underwent PWI with (RVP group,
n
= 50) or without RVP (control group,
n
= 50).
Results
The nadir CB temperature (NCT) during the LA-RB and LA-BB creation was significantly lower in the RVP group than control group (LA-RB − 45.7 °C and − 43.9 °C,
p
< 0.001, and LA-BB − 42.4 °C and − 40.0 °C,
p
< 0.001). The success rate of the LA-RB creation was significantly higher in the RVP group than the control group (98% vs. 88%,
p
= 0.039), however, there were no significant differences regarding the LA-BB creation (66% vs. 52%,
p
= 0.15) and PWI (66% vs. 50%,
p
= 0.1) between the two groups. The PWI success rate did not differ whether CB freezing was prematurely terminated due to an excessive luminal esophageal temperature (LET) drop in the RVP group (65.8% vs. 66.7%, respectively,
p
= 0.96).
Conclusions
RVP significantly decreased the NCT during the CB application resulting in the significant improvement of success rate of the LA-RB. The advantage of RVP in terms of the accomplishing PWI was not affected even when the CB freezing was prematurely terminated due to an excessive LET drop.
Background:Efficacy of catheter ablation (CA) of asymptomatic persistent atrial fibrillation (AF) remains unclear. We assessed the quality of life (QOL), exercise performance (EP), and plasma B-type ...natriuretic peptide (BNP) levels following CA in patients with asymptomatic AF.Methods and Results:We enrolled 34 patients with asymptomatic persistent AF. QOL, was assessed by 2 questionnaires: the Short Form-36 (SF-36) and a QOL questionnaire specific for AF (AFQLQ). The QOL, EP, and plasma BNP level were examined before and 6 months after CA. In the SF-36 survey 5 of 8 components and all 3 subsets of the AFQLQ significantly improved in the patients without recurrences (30 patients, 88%), but there were no differences in those with recurrences. In patients without recurrences, there was an increase in the metabolic equivalents of task (10.2±2.3 vs. 11.6±2.3 METs, P<0.0001), duration of maximal exercise (476±144 vs. 605±143 s, P<0.0001), and plasma BNP decrease (146.6±124.3 vs. 33.8±35.6 pg/dL, P<0.0001), with a linear correlation in the increased duration of exercise and plasma BNP decrease (R=0.620, P<0.0001).Conclusions:Maintenance of sinus rhythm after successful CA improved the QOL, EP, and plasma BNP level in patients with asymptomatic persistent AF. CA may be primarily applicable in such patients with previously unrecognized impairment in their QOL and EP.
Summary
Cellular senescence is an important phenomenon in decreased cellular function. Recently, it was shown that cellular senescence is induced in proliferating cells within a short period of time ...by oxidative stresses. This phenomenon is known as premature senescence. However, it is still unknown whether premature senescence can be also induced in cardiomyocytes. The aim of the present study was to investigate whether a senescence‐like phenotype can be induced in cardiomyocytes by oxidative stress. In cardiomyocytes obtained from aged rats (24 months of age), the staining for senescence‐associated β‐galactosidase increased significantly and the protein or RNA levels of cyclin‐dependent kinase inhibitors increased compared to those of young rats. Decreased cardiac troponin I phosphorylation and telomerase activity were also observed in aged cardiomyocytes. Treatment of cultured neonatal rat cardiomyocytes with a low concentration of doxorubicin (DOX) (10−7 mol L−1) did not induce apoptosis but did induce oxidative stress, which was confirmed by 2′,7′‐dichlorofluorescin diacetate staining. In DOX‐treated neonatal cardiomyocytes, increased positive staining for senescence‐associated β‐galactosidase, cdk‐I expression, decreased cardiac troponin I phosphorylation, and decreased telomerase activity were observed, as aged cardiomyocytes. Alterations in mRNA expression typically seen in aged cells were observed in DOX‐treated neonatal cardiomyocytes. We also found that promyelocytic leukemia protein and acetylated p53, key proteins involved in stress‐induced premature senescence in proliferating cells, were associated with cellular alterations of senescence in DOX‐treated cardiomyocytes. In conclusion, cardiomyocytes treated with DOX showed characteristic changes similar to cardiomyocytes of aged rats. promyelocytic leukemia‐related p53 acetylation may be an underlying mechanism of senescence‐like alterations in cardiomyocytes. These findings indicate a novel mechanism of myocardial dysfunction induced by oxidative stress.
Background:Catheter ablation (CA) is a common treatment for atrial fibrillation (AF). Although rivaroxaban is increasingly used as a substitute for warfarin, its safety and efficacy during CA have ...not been established in Japanese patients. In the present study we explored the efficacy/safety of rivaroxaban during the CA perioperative period.Methods and Results:We prospectively enrolled Japanese AF patients scheduled for CA who had received either rivaroxaban (rivaroxaban cohort, JACRE-R) or warfarin (warfarin cohort, JACRE-W) during the perioperative period. Primary outcome was a composite of thromboembolism and major bleeding within 30 days after CA. In JACRE-R and JACRE-W, 1,118 (median age, 65 years) and 204 patients (median, 69 years) were enrolled from 42 and 22 institutions, respectively. In JACRE-R, the primary outcome occurred in 7 patients (0.6%), comprising thromboembolism in 2 and major bleeding in 5. Non-major bleeding occurred in 27 patients (2.4%), and the incidence was significantly lower in patients without heparin bridging (n=572) than in those with heparin bridging (n=546). In JACRE-W, the primary outcome occurred in 3 patients (1.5%), all of which were major bleeding. After adjustment for patients’ characteristics, no significant difference was observed between the JACRE-R and JACRE-W cohorts for the primary outcome.Conclusions:The rates of thromboembolism and major bleeding events during the AF ablation perioperative period in Japanese patients treated with rivaroxaban was as low as in those treated with warfarin. (Circ J 2016; 80: 2295–2301)
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