Effect of Oral Care on Endothelial Dysfunction in Patients with Acute Coronary Syndrome.

Periodontitis is a common chronic infection and is associated with cardiovascular disease. This study evaluated whether basic oral care for periodontal disease could improve endothelial function in patients with acute coronary syndrome (ACS).This study enrolled 54 patients with acute coronary syndrome admitted to Kagoshima City Hospital and who had undergone percutaneous coronary intervention. Flow-mediated endothelium-dependent dilatation (FMD) was measured before discharge (initial FMD) and at 8 months after percutaneous coronary intervention (follow-up FMD). The following periodontal characteristics were measured: periodontal pocket depth (PPD, mm), plaque control record (%), and bleeding on probing (%). All patients received basic oral care instructions from dentists. The oral health condition was generally poor in the participants and there were 24 patients (44.4%) who had severe PPD. Despite the intervention of basic oral care, the periodontal characteristics did not improve during the study period; initial FMD and follow-up FMD did not significantly differ (4.38 ± 2.74% versus 4.56 ± 2.51%, P = 0.562). However, the follow-up FMD was significantly lower in patients with severe PPD (≥ 6.0 mm, n = 24) than in patients without severe PPD (≤ 5.0 mm, n = 30) (FMD: 3.58 ± 1.91% versus 5.37 ± 2.67%, P = 0.007). FMD tended to be worse in patients with severe PPD than in patients without severe PPD (ΔFMD: -0.55 ± 2.12 versus 0.81 ± 2.77 %, P = 0.055). In conclusion, during the use of basic oral care, endothelial function improved in patients without severe PPD, while it worsened in patients with severe PPD.

Cardio-Ankle Vascular Index and Left Atrial Reverse Remodeling After Ablation for Atrial Fibrillation.

Arterial stiffness has been reported to cause left atrial (LA) remodeling due to increased left ventricular filling pressure, resulting in atrial fibrillation (AF). This study aimed to evaluate the association between LA reverse remodeling (LARR) after AF ablation and cardio-ankle vascular index (CAVI), an indicator of arterial stiffness.This study included 333 patients with AF (171 with paroxysmal AF and 162 with nonparoxysmal AF) and LA enlargement (LA volume index ≥ 34 mL/m2) who underwent AF ablation between December 2008 and July 2021. CAVI was evaluated preoperatively during AF (n = 155, 46.5%) or sinus rhythm (n = 178, 53.5%). Participants were divided into groups with LARR (n = 133, 39.9%) and without LARR (n = 200, 60.1%) according to whether the degree of decrease in LA volume index on transthoracic echocardiography 6 months after ablation was ≥ 15% or < 15%, respectively.Sinus rhythm was maintained in 168 (50.5%) patients within 3-6 months after the index procedure. Univariate analysis revealed that preoperative CAVI (7.80 ± 1.22 versus 8.57 ± 1.09, P < 0.001) was significantly lower, and the maintenance of sinus rhythm (61.6% versus 43.0%, P = 0.0011) was higher in the group with LARR. Multivariate logistic regression analysis revealed that preoperative CAVI was independently associated with LARR (odds ratio, 0.60, 95% confidence interval, 0.46-0.78, P < 0.001).In patients with AF and LA enlargement, CAVI is independently associated with LA reverse remodeling after catheter ablation.

Home Sleep Apnea Test to Screen Patients With Atrial Fibrillation for Sleep Apnea Prior to Catheter Ablation.

BACKGROUND: Whether all atrial fibrillation (AF) patients should be evaluated for sleep apnea before catheter ablation (CA) remains controversial. Watch-type peripheral arterial tonometry (W-PAT) is a home sleep testing device and an easier tool for diagnosing sleep apnea than polysomnography. We investigated the prevalence and predictors of sleep apnea using W-PAT in unscreened sleep apnea patients with AF before CA.Methods and Results:The study was conducted under a retrospective, single-center, observational design. We included 776 consecutive patients who underwent both W-PAT and AF ablation. Sleep apnea assessments were successfully performed in 774 patients (99.7%; age 65±11 years, 73.3% male; body mass index [BMI] 24.1±3.5, 56.8% paroxysmal AF). The mean apnea-hypopnea index (AHI) was 20.1±15.6. Although 81.7% of the patients had normal Epworth sleepiness scores (mean 6.5), only 88 (11.4%) had a normal AHI (AHI <5) and 412 (53.2%) had moderate-severe sleep apnea (AHI ≥15). Obesity, male sex, nonparoxysmal AF, hypertension, and a left atrial diameter (LAd) ≥40 mm were predictors of moderate-severe sleep apnea. However, the prevalence of moderate-severe sleep apnea in patients without those predictors (i.e., non-obesity (44.2%), female sex (43.0%), paroxysmal AF (43.9%), no hypertension (45.5%)), and LAd <40 mm (41.0%) was considerably high. CONCLUSIONS: Almost all patients successfully underwent W-PAT to diagnose sleep apnea. Patients undergoing AF ablation had a high prevalence of sleep apnea, and screening for sleep apnea was important in those patients even if they did not have sleepiness or risk factors.

Sex-specific relationship between abdominal obesity and new-onset atrial fibrillation in the general Japanese population.

The incidence of atrial fibrillation (AF) is expected to increase with increasing obesity and number of geriatric patients in Japan. Although higher body mass index and abdominal obesity are associated with an increased risk of AF, the sex-specific relationship between abdominal obesity and new-onset AF is unclear. This study aimed to investigate the sex-specific relationship between abdominal obesity and new-onset AF. This retrospective study evaluated the annual health checkup data of 67,379 adults (33,562 males; age, 54 ± 10 years) without baseline AF from April 2008 to March 2016. Participants were grouped according to waist circumference (WC): large-WC group (males, ≥ 85 cm; females, ≥ 90 cm) and normal-WC group. Logistic regression analyses were performed to determine the strength of the association between abdominal obesity and new-onset AF, overall and separately for males and females. During a median follow-up of 5 years, 280 (0.4%) new cases of AF were recorded. Univariate analysis revealed a significant increase in new-onset AF in males (odds ratio [OR], 1.97; 95% confidence interval [CI], 1.49-2.60; p < 0.001) but not in females (OR, 1.69; 95% CI, 0.96-2.97; p = 0.068) in the large-WC group. After adjusting for clinical variables, multivariate analysis revealed that a large WC was significantly associated with new-onset AF in males (OR, 1.76; 95% CI, 1.31-2.36; p < 0.001) but not in females (OR, 1.22; 95% CI, 0.68-2.18; p = 0.514). Abdominal obesity is associated with an increased risk of new-onset AF in men.

c-Src promotes tumor progression through downregulation of microRNA-129-1-3p.

MicroRNAs (miRNAs) fine-tune cellular signaling by regulating expression of signaling proteins, and aberrant expression of miRNAs is observed in many cancers. The tyrosine kinase c-Src is upregulated in various human cancers, but the molecular mechanisms underlying c-Src-mediated tumor progression remain unclear. In previous investigations of miRNA-mediated control of c-Src-related oncogenic pathways, we identified miRNAs that were downregulated in association with c-Src transformation and uncovered the signaling networks by predicting their target genes, which might act cooperatively to control tumor progression. Here, to further elucidate the process of cell transformation driven by c-Src, we analyzed the expression profiles of miRNAs in a doxycycline-inducible Src expression system. We found that miRNA (miR)-129-1-3p was downregulated in the early phase of c-Src-induced cell transformation, and that reexpression of miR-129-1-3p disrupted c-Src-induced cell transformation. In addition, miR-129-1-3p downregulation was tightly associated with tumor progression in human colon cancer cells/tissues. Expression of miR-129-1-3p in human colon cancer cells caused morphological changes and suppressed tumor growth, cell adhesion, and invasion. We also identified c-Src and its critical substrate Fer, and c-Yes, a member of the Src family of kinases, as novel targets of miR-129-1-3p. Furthermore, we found that miR-129-1-3p-mediated regulation of c-Src/Fer and c-Yes is important for controlling cell adhesion and invasion. Downregulation of miR-129-1-3p by early activation of c-Src increases expression of these target genes and synergistically promotes c-Src-related oncogenic signaling. Thus, c-Src-miR-129-1-3p circuits serve as critical triggers for tumor progression in many human cancers that harbor upregulation of c-Src.

Burden and Long Firing of Premature Atrial Contraction Early After Catheter Ablation Predict Late Recurrence of Atrial Fibrillation.

BACKGROUND: Associations between characteristics of premature atrial contraction (PAC) 6 months after catheter ablation (CA) and later recurrence are not known. We investigated the effects of PAC characteristics on long-term outcomes of initially successful atrial fibrillation (AF) ablation.Methods and Results:In all, 378 patients (mean age 61 years, 21% female, 67% paroxysmal AF) who underwent initial radiofrequency CA for AF without recurrence up to 24-h Holter monitoring 6 months after the procedure were reviewed retrospectively. The calculated number of PAC/24 h and the length of the longest PAC run during Holter recording were analyzed. After 4.3±1.2 years (mean±SD) follow-up, 123 (32.5%) patients experienced late recurrence. Patients with recurrence had significantly more PAC/24 h (median [interquartile range] 110 [33-228] vs. 42 [16-210]; P<0.01) and a longer longest PAC run (5 [2-8] vs. 3 [1-5]; P<0.01) than those without. Receiver operating characteristic curve analysis indicated 58 PAC/24 h and a longest PAC run of 5 were optimal cut-off values for predicting recurrence. After adjusting for previously reported predictors of late recurrence, frequent PAC (≥58/24 h) and longest PAC run ≥5 were found to be independent predictors of late recurrence (hazard ratios [95% confidence intervals] 1.93 [1.24-3.02; P<0.01] and 1.81 [1.20-2.76; P<0.01], respectively). CONCLUSIONS: Six months after successful AF ablation, both frequent PAC and long PAC run are independent predictors of late recurrence.

Comparison of the Safety and Efficacy of Automated Annotation-Guided Radiofrequency Ablation and 2nd-Generation Cryoballoon Ablation in Paroxysmal Atrial Fibrillation.

BACKGROUND: Automated ablation lesion annotation with optimal settings for parameters including contact force (CF) and catheter stability may be effective for achieving durable pulmonary vein isolation. Methods and Results: We retrospectively examined 131 consecutive patients who underwent initial catheter ablation (CA) for paroxysmal atrial fibrillation (PAF) by automatic annotation system (VISITAG module)-guided radiofrequency CA (RFCA) (n=61) and 2nd-generation cryoballoon ablation (CBA) (n=70) in terms of safety and long-term efficacy. The automatic annotation criteria for the RFCA group were as follows: catheter stability range of motion ≤1.5 mm, duration ≥5 s, and CF ≥5 g. We ablated for >20 s with a force-time integral >150 gs at each site, before moving to the next site. Each interlesion distance was <6 mm. Procedural complications were more frequent in the CBA group (1.6% vs. 10.0%, P=0.034). Across a median follow-up of 2.98 years, 88.5% and 70.0% of patients in the RFCA and CBA groups, respectively, were free from recurrence (log-rank test, P=0.0039). There was also a significant difference in favor of RFCA with respect to repeat ablations (3.3% vs. 24.3%, log-rank test, P=0.0003). CONCLUSIONS: RF ablation guided by an automated algorithm that includes CF and catheter stability parameters showed better long-term outcomes than CBA in the treatment of patients with PAF without increasing complications.

Multiple Shifts of the Earliest Retrograde Atrial Activation Site Along the Tricuspid Annulus During the Fast-Slow Form of Atrioventricular Nodal Reentrant Tachycardia by Radiofrequency Modification.

A 70-year-old woman was admitted for treatment of supraventricular tachycardia. Ventriculoatrial conduction was revealed through programmed ventricular stimulation; the coronary sinus ostium (CSos) was the earliest atrial activation site. The fast-slow forms of atrioventricular nodal reentrant tachycardia (AVNRT) were induced by ventricular extra-stimuli. During tachycardia, the earliest atrial activation site was located at the bottom of CSos. Radiofrequency (RF) energy application to this site resulted in the delay of local electrical potential, prolongation of tachycardia cycle length, and a shift of the earliest retrograde activation site to the roof of CSos. Subsequent ablation induced a similar shift to the inferior tricuspid annulus and to the right posterior septum. Finally, RF energy application to the right posterior septum resulted in the termination of tachycardia, which was not induced afterward. Multiple shifts in the earliest retrograde atrial activation site along the tricuspid annulus after each slow pathway ablation suggested that annular tissue plays a substantial role as a substrate for AVNRT.

Efficacy and Safety of Figure-of-Eight Suture for Hemostasis After Radiofrequency Catheter Ablation for Atrial Fibrillation.

BACKGROUND: This study evaluated the safety and efficacy of venous figure-of-eight (FoE) suture to achieve femoral venous hemostasis after radiofrequency (RF) catheter ablation (CA) for atrial fibrillation (AF).Methods and Results:We retrospectively examined 517 consecutive patients undergoing RFCA for AF. The control group (n=247) underwent manual compression for femoral venous hemostasis after sheath removal with 6 h of bed rest. The FoE group (n=270) underwent FoE suture technique with 4 h of bed rest. All patients achieved successful hemostasis within 24 h after CA. Although the incidence of hematoma was similar between the groups, the incidence of rebleeding was lower in the FoE group than in the control group (FoE vs. control, 3.7% vs. 18.6%, P<0.001). The post-procedural use of analgesic and/or anti-emetic agents was less frequent in the FoE group (19.3% vs. 32.0%, P<0.001). On multiple logistic regression analysis after adjustment for age and sex, the use of a vitamin K antagonist (OR, 2.42; 95% CI: 1.18-4.99, P=0.02) and the FoE suture technique (OR, 0.17; 95% CI: 0.08-0.35, P<0.001) were independent predictors of rebleeding after CA. CONCLUSIONS: FoE suture technique effectively achieved femoral venous hemostasis after RFCA for AF. It reduced the risk of rebleeding, shortened bed rest duration, and relieved patient discomfort.

Tysnd1 deficiency in mice interferes with the peroxisomal localization of PTS2 enzymes, causing lipid metabolic abnormalities and male infertility.

Peroxisomes are subcellular organelles involved in lipid metabolic processes, including those of very-long-chain fatty acids and branched-chain fatty acids, among others. Peroxisome matrix proteins are synthesized in the cytoplasm. Targeting signals (PTS or peroxisomal targeting signal) at the C-terminus (PTS1) or N-terminus (PTS2) of peroxisomal matrix proteins mediate their import into the organelle. In the case of PTS2-containing proteins, the PTS2 signal is cleaved from the protein when transported into peroxisomes. The functional mechanism of PTS2 processing, however, is poorly understood. Previously we identified Tysnd1 (Trypsin domain containing 1) and biochemically characterized it as a peroxisomal cysteine endopeptidase that directly processes PTS2-containing prethiolase Acaa1 and PTS1-containing Acox1, Hsd17b4, and ScpX. The latter three enzymes are crucial components of the very-long-chain fatty acids ß-oxidation pathway. To clarify the in vivo functions and physiological role of Tysnd1, we analyzed the phenotype of Tysnd1(-/-) mice. Male Tysnd1(-/-) mice are infertile, and the epididymal sperms lack the acrosomal cap. These phenotypic features are most likely the result of changes in the molecular species composition of choline and ethanolamine plasmalogens. Tysnd1(-/-) mice also developed liver dysfunctions when the phytanic acid precursor phytol was orally administered. Phyh and Agps are known PTS2-containing proteins, but were identified as novel Tysnd1 substrates. Loss of Tysnd1 interferes with the peroxisomal localization of Acaa1, Phyh, and Agps, which might cause the mild Zellweger syndrome spectrum-resembling phenotypes. Our data established that peroxisomal processing protease Tysnd1 is necessary to mediate the physiological functions of PTS2-containing substrates.

Exploration of reference genes for the development of a diagnostic kit on vascular aging in human saliva.

Identifying reliable biomarkers in saliva can be a promising approach to developing a rapid diagnostic kit for detecting vascular aging. This study investigated the most suitable reference gene for polymerase chain reaction (PCR) in saliva that is not affected by vascular aging variables. Whole saliva samples were collected to assess the expression of reference genes: actin beta (ACTB), 18S ribosomal RNA (18S rRNA), beta-2-microglobulin, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). The most abundantly expressed gene was 18S rRNA, and the least expressed gene was GAPDH. Four genes were ranked according to their relative stability, as determined by mathematical algorithms, indicating that ACTB and 18S rRNA were stably expressed as reference genes. 18S rRNA was identified as the most promising reference gene for detecting systemic diseases using saliva from patients with vascular aging in these limited experimental conditions.

Incidence and predictors of persistent iatrogenic atrial septal defect following catheter ablation.

BACKGROUND: The left atrium approach for atrial fibrillation (AF) ablation requires an atrial transseptal puncture that may cause an iatrogenic atrial septal defect (iASD). This study aimed to investigate the incidence and predictors of iASD in catheter ablation, assessed by transthoracic echocardiography (TTE), a relatively non-invasive technique frequently employed in follow-up. METHODS: This retrospective study included 639 patients (489 male; 60.2 ±â€¯10.7 years) who underwent initial catheter ablation for AF between May 2005 and June 2018. All patients underwent preprocedural transesophageal echocardiography (pre-TEE), preprocedural TTE (pre-TTE), and TTE one day after the procedure (post-TTE). iASD incidence after 6 months (6 M), preprocedural characteristics, and procedure methods were evaluated. RESULTS: Patent foramen ovale (PFO) was diagnosed in 42 patients (6.6 %) using pre-TEE and in 11 patients using pre-TTE (26.2 % of the patients with PFO in pre-TEE). Among the 597 patients without PFO, 497 underwent 6 M-TTE. iASD was observed in 59.6 % of patients using post-TTE and 4.6 % using 6 M-TTE. In the univariate logistic regression analysis, the total diameter of the sheath through the septum (odds ratio 1.15, p < 0.001) or two sheaths through a single puncture (odds ratio 4.17, p = 0.001) were independent risk factors on iASD incidence in 6 M-TTE. iASD was also more likely to occur via cryoballoon ablation using a larger sheath than radiofrequency catheter ablation. CONCLUSIONS: iASD was not a rare complication. A larger sheath diameter or two sheaths through a single puncture were associated with the incidence of iASD.

Simple risk scoring using sinus rhythm electrocardiograms predicts the incidence of atrial fibrillation in the general population.

Atrial fibrillation (AF) is an arrhythmic disease. Prediction of AF development in healthy individuals is important before serious complications occur. We aimed to develop a risk prediction score for future AF using participants' data, including electrocardiogram (ECG) measurements and information such as age and sex. We included 88,907 Japanese participants, aged 30-69 years, who were randomly assigned to derivation and validation cohorts in a ratio of 1:1. We performed multivariate logistic regression analysis and obtained the standardised beta coefficient of relevant factors and assigned scores to them. We created a score based on prognostic factors for AF to predict its occurrence after five years and applied it to validation cohorts to assess its reproducibility. The risk score ranged from 0 to 17, consisting of age, sex, PR prolongation, QT corrected for heart rate prolongation, left ventricular hypertrophy, premature atrial contraction, and left axis deviation. The area under the curve was 0.75 for the derivation cohort and 0.73 for the validation cohort. The incidence of new-onset AF reached over 2% at 10 points of the risk score in both cohorts. Thus, in this study, we showed the possibility of predicting new-onset AF using ECG findings and simple information.

Association between weight gain following smoking cessation and development of hypertension in the future.

Although quitting smoking lowers the risk of developing chronic conditions, it usually leads to weight gain. Literature on the association between weight gain after quitting smoking and the future development of hypertension is scarce. Among 234 596 individuals who visited our health center, 856 who had quit smoking for whom data were available at least 6 years after smoking cessation were included. We evaluated changes in blood pressure and antihypertensive drug prescription rate at 1 and 6 years after smoking cessation. We also compared weight and blood pressure between the smoking cessation and continued smoking groups after 6 years. Multiple regression analyses were performed to identify predictors of changes in systolic and diastolic blood pressures using covariates affecting blood pressure. Since a median weight gain of 1.8 kg was observed at 1 year after smoking cessation, we divided the participants into high and low-weight gain groups. No significant intergroup difference in the antihypertensive drug prescription rate was observed after 6 years. The high weight gain group showed significant increases in systolic and diastolic blood pressures after 6 years. Multiple regression analyses revealed that systolic blood pressure was affected by age and high weight gain, while diastolic blood pressure was affected by high weight gain. Our findings suggest that weight gain following smoking cessation leads to blood pressure elevation: the smoking cessation group gained more weight and had higher blood pressure than the continued smoking group. Therefore, weight loss guidance may be useful for individuals who want to quit smoking. Participants in the high weight gain group showed significant increases in systolic and diastolic blood pressures at 6 years after smoking cessation that were significantly different from those observed in participants in the low weight gain group and the continued smoking group.

Multicenter prospective observational study to clarify the current status and clinical outcome in Japanese patients who have an indication for implantable cardioverter defibrillator (ICD) or wearable cardioverter defibrillator (WCD) (TRANSITION JAPAN-ICD/WCD study): Rationale and design of a prospective, multicenter, observational, comparative study.

Background: Despite the positive impact of implantable cardioverter defibrillators (ICDs) and wearable cardioverter defibrillators (WCDs) on prognosis, their implantation is often withheld especially in Japanese heart failure patients with reduced left ventricular ejection fraction (HFrEF) who have not experienced ventricular tachycardia (VT) or ventricular fibrillation (VF) for uncertain reasons. Recent advancements in heart failure (HF) medications have significantly improved the prognosis for HFrEF. Given this context, a critical reassessment of the treatment and prognosis of ICDs and WCDs is essential, as it has the potential to reshape awareness and treatment strategies for these patients. Methods: We are initiating a prospective multicenter observational study for HFrEF patients eligible for ICD in primary and secondary prevention, and WCD, regardless of device use, including all consenting patients. Study subjects are to be enrolled from 31 participant hospitals located throughout Japan from April 1, 2023, to December 31, 2024, and each will be followed up for 1 year or more. The planned sample size is 651 cases. The primary endpoint is the rate of cardiac implantable electronic device implementation. Other endpoints include the incidence of VT/VF and sudden death, all-cause mortality, and HF hospitalization, other events. We will collect clinical background information plus each patient's symptoms, Clinical Frailty Scale score, laboratory test results, echocardiographic and electrocardiographic parameters, and serial changes will also be secondary endpoints. Results: Not applicable. Conclusion: This study offers invaluable insights into understanding the role of ICD/WCD in Japanese HF patients in the new era of HF medication.

The incidence of asymptomatic cerebral microthromboembolism after atrial fibrillation ablation: comparison of warfarin and dabigatran.

BACKGROUND: Cerebral microthromboembolism after atrial fibrillation (AF) ablation has been reported in 4-20% with perioperative warfarin. Dabigatran is a new anticoagulant in patients with nonvalvular AF. We investigated the incidence of asymptomatic cerebral microthromboembolism after AF ablation with perioperative warfarin or dabigatran using diffusion-weighted and T2-weighted magnetic resonance imaging (MRI). METHODS AND RESULTS: Our study included 210 consecutive patients with AF (111 paroxysmal and 99 persistent) who underwent complex fractionated atrial electrogram-guided ablation (combined with pulmonary vein isolation, n = 110). Catheter irrigation was performed in all cases. Uninterrupted warfarin therapy was used in 180 patients (warfarin group) and interrupted only on the morning of the procedure with dabigatran in 30 (dabigatran group). All patients underwent cerebral MRI the day after ablation. New microthromboemboli were detected in 10.0% of the warfarin group and 26.7% of the dabigatran group (P < 0.05). The incidence of hemopericardium treated with pericardiocentesis was lower in the warfarin group than in the dabigatran group (2.5% vs 11.1%, P < 0.05). In multivariate analysis, the use of cardioversion was a predictor of new microthromboembolism development after AF ablation. CONCLUSIONS: The incidence of asymptomatic cerebral microthromboembolism and hemopericardium after AF ablation was significantly lower with perioperative warfarin therapy than with dabigatran therapy. Dabigatran may not be an effective alternative to warfarin for AF ablation, especially in patients who undergo cardioversion.

Id4, a new candidate gene for senile osteoporosis, acts as a molecular switch promoting osteoblast differentiation.

Excessive accumulation of bone marrow adipocytes observed in senile osteoporosis or age-related osteopenia is caused by the unbalanced differentiation of MSCs into bone marrow adipocytes or osteoblasts. Several transcription factors are known to regulate the balance between adipocyte and osteoblast differentiation. However, the molecular mechanisms that regulate the balance between adipocyte and osteoblast differentiation in the bone marrow have yet to be elucidated. To identify candidate genes associated with senile osteoporosis, we performed genome-wide expression analyses of differentiating osteoblasts and adipocytes. Among transcription factors that were enriched in the early phase of differentiation, Id4 was identified as a key molecule affecting the differentiation of both cell types. Experiments using bone marrow-derived stromal cell line ST2 and Id4-deficient mice showed that lack of Id4 drastically reduces osteoblast differentiation and drives differentiation toward adipocytes. On the other hand knockdown of Id4 in adipogenic-induced ST2 cells increased the expression of Ppargamma2, a master regulator of adipocyte differentiation. Similar results were observed in bone marrow cells of femur and tibia of Id4-deficient mice. However the effect of Id4 on Ppargamma2 and adipocyte differentiation is unlikely to be of direct nature. The mechanism of Id4 promoting osteoblast differentiation is associated with the Id4-mediated release of Hes1 from Hes1-Hey2 complexes. Hes1 increases the stability and transcriptional activity of Runx2, a key molecule of osteoblast differentiation, which results in an enhanced osteoblast-specific gene expression. The new role of Id4 in promoting osteoblast differentiation renders it a target for preventing the onset of senile osteoporosis.

Incidence of asymptomatic cerebral microthromboembolism after atrial fibrillation ablation guided by complex fractionated atrial electrogram.

BACKGROUND: The incidence of cerebral thromboembolism after pulmonary vein isolation (PVI) ranges from 2% to 14%. This study investigated the incidence of cerebral thromboembolism after complex fractionated atrial electrogram (CFAE) ablation with or without PVI. METHODS: One hundred consecutive atrial fibrillation (AF) patients (50 paroxysmal and 50 persistent, including 10 longstanding) who underwent CFAE ablation combined with (n = 41, PVI+CFAE group) or without (n = 59, CFAE group) PVI were studied. Coronary angiography (CAG) was conducted with AF ablation in 5 cases in which coronary artery stenosis was suspected on 3D-computed tomography. PVI was performed before CFAE ablation without circular catheter during AF. After termination of AF, additional ablation was performed to complete PVI with a circular catheter. All patients underwent cerebral magnetic resonance imaging (MRI) including diffusion-weighted MRI and T2-weighted MRI the day after ablation. RESULTS: New thromboembolism was detected in 7.0%, and there was no significant difference between the 2 strategies (7.3% in PVI+CFAE group, 6.8% in CFAE group). CHADS2 score (1.6 ± 1.0 vs 0.8 ± 0.9, P < 0.05), left atrial volume (LAV; 83.8 ± 27.1 vs 67.8 ± 21.8, P < 0.05), and left ventricular ejection fraction (LVEF, 53.1 ± 9.2 vs 65.1 ± 9.7, P < 0.01) were significantly different when comparing patients with or without thromboembolism. In multivariate analysis, LVEF (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.84-0.99; P < 0.05) and concomitant CAG (OR 18.82; 95% CI, 1.77-200.00; P < 0.05) were important predictors of new cerebral thromboembolism. CONCLUSIONS: The incidence of cerebral microthromboembolism after CFAE ablation was not greater than previous reports in PVI. Cautious management is required during AF ablation, especially in the patients with low LVEF.

Absence of first-pass isolation is associated with poor pulmonary vein isolation durability and atrial fibrillation ablation outcomes.

BACKGROUND: Pulmonary vein (PV) reconnection is the main cause of atrial fibrillation (AF) recurrence. This study aimed to examine the effect of first-pass PV isolation (PVI) on PV reconnection frequency during the procedure and on AF ablation outcomes. METHODS: This retrospective study included 446 patients with drug-refractory AF (370 men, aged 64 ± 10 years) who underwent initial PVI using an open-irrigated contact force catheter between January 2015 and October 2016. We investigated the effect of first-pass PVI on PV reconnection during spontaneous PV reconnection and dormant conduction after an adenosine triphosphate challenge. RESULTS: First-pass PVI was achieved in 69% (617/892) of ipsilateral PVs, of which we observed PV reconnection during the procedure in 134 (22%) PVs. This value was significantly lower than that observed in those without first-pass PVI (50%, 138/275) (P < .0001). We divided the subjects into two groups based on the presence or absence of first-pass PVI in at least one of two ipsilateral PVs: first-pass (n = 383, 86%) and non-first-pass groups (n = 63, 14%). The 2-year AF recurrence-free rate was significantly higher in the first-pass group than in the other group (75% vs 59%, log-rank P = .032). In 78 patients with repeat AF ablation, the PV reconnection rate in the second procedure was significantly lower in PVs that had first-pass isolation in the first procedure (34% vs 73%, P < .0001). CONCLUSIONS: Absence of first-pass PVI was associated with a higher frequency of spontaneous PV reconnection and dormant conduction and poor ablation outcomes. First-pass isolation may be a useful marker for better PVI durability.

Clinical significance of left ventricular reverse remodeling after catheter ablation of atrial fibrillation in patients with left ventricular systolic dysfunction.

BACKGROUND: Left ventricular (LV) reverse remodeling (LVRR) after catheter ablation of atrial fibrillation (AFCA) has not been fully described. This study investigated the predictors and clinical outcomes of LVRR after AFCA in patients with LV systolic dysfunction. METHODS: Of 3319 consecutive patients who underwent first-time AFCA between January 2012 and October 2019, 376 with a baseline LV ejection fraction of <50% were retrospectively evaluated. They were subjected to 256-slice multidetector computed tomography (MDCT) scanning at baseline and 3 months after AFCA. The LVRR was defined as a decrease in the LV end-systolic volume of ≥15%. RESULTS: The prevalence of LVRR was 83% (n = 306). Multivariate logistic regression analysis including age, body mass index, diabetic status, beta-blocker use, and LV diastolic diameter revealed that the predictors of LVRR were non-paroxysmal atrial fibrillation (AF) (odds ratio, 2.68; 95% confidence interval, 1.42-5.05; p = 0.002) and absence of apparent underlying structural heart disease (4.81; 2.31-10.0; p <0.001). The prevalence of LVRR differed depending on AF recurrence pattern prior to the post-MDCT [no episode vs. paroxysmal episode (lasting <7 days) vs. persistent episode (lasting ≥7 days), 84% vs. 81% vs. 63%, respectively, p = 0.023]. During a median follow-up of 32 months, the incidence of paroxysmal form of AF recurrence was similar, whereas persistent form of AF recurrence was less frequent in patients with LVRR (10.5% vs. 18.6%, p = 0.018). Heart failure hospitalizations (2.3% vs. 15.7%, p <0.001), cardiovascular deaths (0.7% vs. 4.3%, p = 0.015), and all-cause deaths (1.3% vs. 5.7%, p = 0.018) were similarly less frequent in those with LVRR. CONCLUSIONS: LVRR after AFCA, which was predicted by non-paroxysmal AF without any apparent structural heart disease at baseline, was associated with persistent form of AF recurrence prior to the evaluation. LVRR was associated with favorable clinical outcomes.