The impact of early cryoballoon ablation on clinical outcome in patients with atrial fibrillation: From the Korean cryoballoon ablation registry.

INTRODUCTION: Influence of early atrial fibrillation (AF) ablation, particularly cryoballoon ablation (CBA), on clinical outcome during long-term follow-up has not been clarified. The objective was to determine whether an early CBA (diagnosis-to-ablation of ≤6 months) strategy could affect freedom from AF recurrence after index CBA. METHODS: The study included 2605 patients from Korean CBA registry data with follow-up >12 months after de novo CBA. The primary outcome was recurrence of atrial tachyarrhythmias (ATs) of ≥30-s after a 3-month blanking period. RESULTS: Compared to patients in early CBA group, patients in late CBA group had higher prevalence of diabetes, congestive heart failure, and chronic kidney disease, and higher mean CHA2 DS2 -VAS score. During mean follow-up of >21 months, ATs recurrence was detected in 839 (32.2%) patients. The early CBA group showed a significantly lower 2-year recurrence rate of ATs than the late CBA group (26.1% vs. 31.7%, p = 0.043). In subgroup analysis, the early CBA group showed significantly higher 1-year and 2-year freedom from ATs recurrence than the late CBA group only in paroxysmal atrial fibrillation (PAF) patients in overall and propensity score matched cohorts. Multivariate analysis showed that early CBA was an independent factor for preventing ATs recurrence in PAF (hazard ratio: 0.637; 95% confidence intervals: 0.412-0.984). CONCLUSION: Early CBA strategy, resulting in significantly lower ATs recurrence during 2-year follow-up after index CBA, might be considered as an initial rhythm control therapy in patients with paroxysmal AF.

Long-term clinical impact of early recurrence of atrial tachyarrhythmia after cryoballoon ablation in patients with atrial fibrillation.

INTRODUCTION: The impact of early recurrence of atrial tachyarrhythmia (ERAT) within the 90-day blanking period on long-term outcomes in atrial fibrillation (AF) patients undergoing cryoballoon ablation (CBA) is controversial. This study aimed to assess the relationship between ERAT and late recurrence of atrial tachyarrhythmia (LRAT) post-CBA. METHODS: Utilizing data from a multicenter registry in Korea (May 2018 to June 2022), we analyzed the presence and timing of ERAT (<30, 30-60, and 60-90 days) and its association with LRAT risk after CBA. LRAT was defined as any recurrence of AF, atrial flutter, or atrial tachycardia lasting more than 30 s beyond the 90 days. RESULTS: Out of 2636 patients, 745 (28.2%) experienced ERAT post-CBA. Over an average follow-up period of 21.2 ± 10.3 months, LRAT was observed in 874 (33.1%) patients. Patients with ERAT had significantly lower 1-year LRAT freedom compared to those without ERAT (42.6% vs. 85.5%, p < .001). Multivariate analysis identified ERAT as a potential predictor of LRAT, with a hazard ratio (HR) of 3.98 (95% confidence interval [CI], 3.47-4.57). Significant associations were noted across all examined time frames (HR, 3.84; 95% CI, 3.32-4.45 in <30 days, HR, 5.53; 95% CI, 4.13-7.42 in 30-60 days, and HR, 4.29; 95% CI, 3.12-5.89 in 60-90 days). This finding was consistently observed across all types of AF. CONCLUSION: ERAT during the 90-day blanking period strongly predicts LRAT in AF patients undergoing CBA, indicating a need to reconsider the clinical significance of this period.

Association between body mass index and results of cryoballoon ablation in Korean patients with atrial fibrillation: an analysis from the Korean Heart Rhythm Society Cryoablation registry.

AIMS: Pulmonary vein isolation using cryoablation is effective and safe in patients with atrial fibrillation (AF). Although both obesity and underweight are associated with a higher risk for incident AF, there is limited data on the efficacy and safety following cryoablation according to body mass index (BMI) especially in Asians. METHODS AND RESULTS: Using the Korean Heart Rhythm Society Cryoablation registry, a multicentre registry of 12 tertiary hospitals, we analysed AF recurrence and procedure-related complications after cryoablation by BMI (kg/m2) groups (BMI < 18.5, underweight, UW; 18.5-23, normal, NW; 23-25, overweight, OW; 25-30, obese Ⅰ, OⅠ; ≥30, obese Ⅱ, OⅡ). A total of 2648 patients were included (median age 62.0 years; 76.7% men; 55.6% non-paroxysmal AF). Patients were categorized by BMI groups: 0.9% UW, 18.7% NW, 24.8% OW, 46.1% OI, and 9.4% OII. Underweight patients were the oldest and had least percentage of non-paroxysmal AF (33.3%). During a median follow-up of 1.7 years, atrial arrhythmia recurred in 874 (33.0%) patients (incidence rate, 18.9 per 100 person-years). After multivariable adjustment, the risk of AF recurrence was higher in UW group compared with NW group (adjusted hazard ratio, 95% confidence interval; 2.55, 1.18-5.50, P = 0.02). Procedure-related complications occurred in 123 (4.7%) patients, and the risk was higher for UW patients (odds ratio, 95% confidence interval; 2.90, 0.94-8.99, P = 0.07), mainly due to transient phrenic nerve palsy. CONCLUSION: Underweight patients showed a higher risk of AF recurrence after cryoablation compared with NW patients. Also, careful attention is needed on the occurrence of phrenic nerve palsy in UW patients.

Safety and efficacy of intracardiac echocardiography-guided zero-fluoroscopic cryoballoon ablation for atrial fibrillation: a prospective randomized controlled trial.

AIMS: The development of intracardiac echocardiography (ICE) has enabled fluoroless atrial fibrillation (AF) ablation using three-dimensional electroanatomical mapping systems. However, fluoroless cryoballoon ablation (CBA) remains challenging, mainly because of the lack of a visual mapping system. Hence, this study aimed to investigate the safety and efficacy of fluoroless CBA for AF under ICE guidance. METHODS AND RESULTS: Patients (n = 100) who underwent CBA for paroxysmal AF were randomly assigned to zero-fluoroscopic (Zero-X) and conventional groups. Intracardiac echocardiography was used to guide the transseptal puncture and catheter and balloon manipulation in all enrolled patients. The patients were prospectively followed for 12 months after CBA. The mean age was 60.4 years, and the left atrial (LA) size was 39.4 mm. Pulmonary vein isolation (PVI) was achieved in all patients. In the Zero-X group, fluoroscopy was used in only one patient because of unstable phrenic nerve capture during right-sided PVI. The procedure time and LA indwelling time in the Zero-X group were not statistically different compared with that in the conventional group. Fluoroscopic time (9.0 vs. 0.008 min) and radiation exposure (29.4 vs. 0.02 mGy) were significantly shorter in the Zero-X group than in the conventional group (P < 0.001). The complication rate did not differ between the two groups. During a mean follow-up of 663.3 ± 172.3 days, the recurrence rate was similar (16.0 vs. 18.0%; P = 0.841) between the groups. Multivariate analysis revealed that LA size was the only independent predictor of clinical recurrence. CONCLUSION: Intracardiac echocardiography-guided fluoroless CBA for AF was a feasible strategy without compromising acute and long-term success or complication rates.

Does isolation of the left atrial posterior wall using cryoballoon ablation improve clinical outcomes in patients with persistent atrial fibrillation? A prospective randomized controlled trial.

AIMS: Posterior wall isolation (PWI) of the left atrium (LA) adjunct to pulmonary vein isolation (PVI) by radiofrequency catheter ablation has shown favourable outcomes in patients with persistent atrial fibrillation (PeAF). This study was sought to investigate the efficacy and safety of additional PWI by cryoballoon ablation (CBA) alone in patients with PeAF. METHODS AND RESULTS: Patients who underwent de novo CBA for PeAF (n = 100) were randomly assigned (1 : 1) to the PVI only group and PVI combined with PWI (PVI+PWI) group. Procedural and clinical outcomes were prospectively compared over a 12-month follow-up.Baseline characteristics, including mean AF duration (56.2 ± 43.2 months) and LA size (48.2 ± 7.7 mm), were well-balanced between the groups. Successful PVI was achieved in all patients. In the PVI+PWI group, complete PWI by CBA was achieved in 31 (62%) patients. The LA indwelling and procedure times were significantly longer in the PVI+PWI group. The complication rates were not different between groups. During a mean follow-up of 457.9 ± 61.8 days, the recurrence rate of atrial tachyarrhythmia was significantly lower in the PVI+PWI group than in the PVI only group (24% vs. 46%; P = 0.035). The recurrence-free survival rate was significantly higher in the PVI+PWI group compared with the PVI only group, irrespective of complete PWI (log-rank P = 0.013). Multivariate analysis showed that adjunctive PWI [hazard ratio (HR) 0.255; P = 0.003] and LA size (HR 1.079; P = 0.014) were independent predictors of clinical recurrence. CONCLUSION: Compared with PVI only, adjunctive PWI achieved exclusively by CBA resulted in better clinical outcomes without increasing complications in patients with PeAF.

Outcomes of On-Label Reduced-Dose Edoxaban in Patients With Atrial Fibrillation: The LEDIOS Registry.

BACKGROUND: Non-vitamin K antagonist oral anticoagulants (NOACs) are effective in preventing thromboembolisms and reduce the risk of bleeding compared with warfarin. There are few reports on the outcomes of on-label reduced-dose NOACs. The aim of this study was to assess the safety and efficacy of on-label reduced-dose edoxaban in patients with atrial fibrillation (AF). METHODS: This study is a multi-center, prospective, non-interventional study to evaluate the safety and efficacy of on-label reduced-dose edoxaban in patients with AF. We evaluated outcomes of major bleeding, stroke or systemic embolism, all-cause death, and composite clinical outcomes. RESULTS: A total of 2,448 patients (mean age 75.0 ± 8.3 years, 801 [32.7%] males) was included in the present study. The mean CHA2DS2-VASc score was 3.7 ± 1.5. Major bleeding events occurred at a rate of 1.34%/yr. The event rate of strokes and systemic embolisms was 1.13%/yr. The overall net clinical outcomes occurred at a rate of 3.19%/yr. There were no significant differences according to the number of dose reduction criteria, renal dysfunction, or body weight. Higher HAS-BLED score and higher combination of CHA2DS2-VASc and HAS-BLED score was associated with an increased risk of composite clinical outcomes compared to the lower score groups. CONCLUSIONS: This study was the largest prospective real-world study to investigate the safety and efficacy of on-label low-dose edoxaban in an Asian population. Reduced-dose edoxaban can be used safely in patients with severe renal dysfunction or extremely low body weight. Our observation suggests that physicians should consider bleeding risk even in a low-dose regimen. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03554837.

Association of pericardial adipose tissue with left ventricular structure and function: a region-specific effect?

BACKGROUND: The independent role of pericardial adipose tissue (PAT) as an ectopic fat associated with cardiovascular disease (CVD) remains controversial. This study aimed to determine whether PAT is associated with left ventricular (LV) structure and function independent of other markers of general obesity. METHODS: We studied 2471 participants (50.9 % women) without known CVD from the Korean Genome Epidemiology Study, who underwent 2D-echocardiography with tissue Doppler imaging (TDI) and computed tomography measurement for PAT. RESULTS: Study participants with more PAT were more likely to be men and had higher cardiometabolic indices, including blood pressure, glucose, and cholesterol levels (all P < 0.001). Greater pericardial fat levels across quartiles of PAT were associated with increased LV mass index and left atrial volume index (all P < 0.001) and decreased systolic (P = 0.015) and early diastolic (P < 0.001) TDI velocities, except for LV ejection fraction. These associations remained after a multivariable-adjusted model for traditional CV risk factors and persisted even after additional adjustment for general adiposity measures, such as waist circumference and body mass index. PAT was also the only obesity index independently associated with systolic TDI velocity (P < 0.001). CONCLUSIONS: PAT was associated with subclinical LV structural and functional deterioration, and these associations were independent of and stronger than with general and abdominal obesity measures.

Ethnic similarities in genetic polymorphisms associated with atrial fibrillation: Far East Asian vs European populations.

BACKGROUND: In European ancestry, 111 genetic loci were identified as associated with atrial fibrillation (AF). We explored the reproducibility of those single nucleotide polymorphisms (SNPs) in a genome-wide association study (GWAS) meta-analysis of Far East Asian populations. METHODS: We performed a meta-analysis of the Korean AF network and Japanese AF data sets (9118 cases and 33 467 controls) by an inverse-variance fixed-effects model. We compared the results with 111 previously reported SNPs proven in Europeans after excluding 36 missing loci and a locus with a minor allelic frequency (MAF) < 0.01 in the European population. RESULTS: Among remaining 74 loci, 29 loci were replicated at a P < .05, and 17 of those loci were newly found in the Far East Asian population: 3 loci with a P < 5×10-8 (METTL11B at 1q24, KCNN2 at 5q22 and LRMDA at 10q22), 4 loci at the threshold of the Bonferroni correction of P = 4.5 × 10-4  ~ 5×10-8 (KIF3C at 2p23, REEP3, NRBF2 at 10q21, SIRT1, MYPN at 10q21 and CFL2 at 14q13) and 10 SNPs with a P = .05 ~ 4.5 × 10-4 . Among 18 AF loci with a MAF< 0.01 in the Far East Asian populations, 2 loci (GATA4 at 8q23 and SGCG at 13q12) were replicated after a fine mapping. Twenty-seven AF loci, including a locus, which had a sufficient sample size to get a power of over 80% (with a type 1 error α = 4.5 × 10-4 ), were not replicated in the Far East Asian populations. CONCLUSIONS: We newly replicated 19 AF-associated genetic loci in the European descent among the Far East Asian populations. It highlights the extensive sharing of AF genetic risks across Far East Asian populations.

Efficacy of high-power and short-duration ablation in patients with atrial fibrillation: a prospective randomized controlled trial.

AIMS: The formation of radiofrequency lesions depends on the power and duration of ablation, and the contact force (CF). Although high power (HP) creates continuous and transmural lesions, most centres still use 25-30 W for 30-40 s for safety reasons. We evaluated the clinical efficacy and safety of a HP and short-duration (HPSD) strategy for atrial fibrillation (AF) ablation. METHODS AND RESULTS: One hundred and fifty patients [58.2 ± 10.0 years, 48% with paroxysmal AF (PAF)] scheduled for index AF ablation using a CF-sensing catheter were randomly assigned to three groups [30 W, 40 W, and 50 W at ablation sites of anterior, roof, and inferior segments of pulmonary vein (PV) antra and roof line between each upper PV]. In 25-30 W for ≤20 s was applied at posterior wall ablation site in all subjects. Compared with the 30 W and 40 W groups, procedure (P < 0.001) and ablation times (P < 0.001) were shorter and ablation number for PV isolation (P < 0.001) was smaller in the 50 W group. There were no significant differences in the CF and ablation index (AI) among the three groups. There were no significant differences in the procedure-related complication rates. During the 12-month follow-up, AF recurred in 24 (16%) patients with no significant difference among the groups (P = 0.769). In the multivariate analysis, non-PAF [hazard ratio (HR) 2.836, P = 0.045] and AI (HR 0.983, P = 0.001) were independent risk factors for AF recurrence. CONCLUSION: Radiofrequency ablation with HPSD is a safe and effective strategy with reduced ablation number and shortened procedure time compared to conventional ablation.

Association between epicardial adipose tissue and embolic stroke after catheter ablation of atrial fibrillation.

INTRODUCTION: Risk factors of embolic stroke (ES) after atrial fibrillation (AF) ablation have not been fully elucidated especially among the Asian subjects, particularly regarding epicardial adipose tissue (EAT) in cardiac imaging. We aimed to assess the incidence of ES during a long-term follow-up period after AF ablation and to identify the risk factors associated with postablation ES, specifically focusing on EAT. METHODS AND RESULTS: We enrolled patients who experienced postablation ES and control subjects from a consortium of AF ablation registries from three institutes in Korea. EAT was assessed using multislice computed tomography before AF ablation. A total of 3464 patients who underwent AF ablation were recruited and followed-up. During a follow-up of 47.2 ± 36.4 months, ES occurred in 47 patients (1.36%) with a CHA2 DS2 -VASc score of 1.48 ± 1.39 and the overall annual incidence of ES was 0.34%. Compared with the control group (n = 190), the ES group showed significantly higher prior thromboembolism (TE) and AF recurrence rates, larger left atrium size, lower creatinine clearance rate (CCr), and greater total and peri-atrial EAT volume. Multivariate regression analysis demonstrated larger peri-atrial EAT volume (hazards ratio, 1.065; 95% confidence interval, 1.005-1.128), in addition to a prior history of TE and lower CCr, was independently associated with postablation ES. When a cut-off value of peri-atrial EAT volume of ≥20.15 mL was applied, patients with smaller peri-atrial EAT volume showed significantly higher ES-free survival. CONCLUSION: Larger peri-atrial EAT volume, in addition to prior TE and lower CCr, was independently associated with postablation ES regardless of AF recurrence and CHA2 DS2 -VASc score. (ClinicalTrials.gov number, NCT03479073).

Selective ß1-Blockers Are Not Associated With New-onset Diabetes Mellitus in Hypertensive Patients.

BACKGROUND: Although ß-blockers are known to increase new-onset diabetes mellitus (DM), previous evidence have been controversial. It has been suggested that newer vasodilatory ß-blockers yield better glycemic control than older nonselective agents. The aim of this study was to evaluate the diabetogenicity of currently used newer ß-blockers based on ß1 receptor selectivity in a series of Asian population. METHODS: We investigated a total of 65,686 hypertensive patients without DM from 2004 to 2014. Patients with hemoglobin (Hb) A1c ≤6.0%, fasting blood glucose ≤110 mg/dL, and no history of diabetes or diabetic treatment were enrolled for analysis. Patients were divided into the ß-blockers group and non-ß-blockers group. Propensity score matching (PSM) analysis using a logistic regression model was performed to adjust for potential confounders. The primary end point was the cumulative incidence of new-onset DM, defined as a fasting blood glucose ≥126 mg/dL or HbA1c ≥6.5%, and major adverse cardiac and cerebral events (MACCE), defined as a composite of total death, nonfatal myocardial infarction, and cerebrovascular accidents. We investigated predictors of new-onset DM and MACCE based on 2 models, including clinical risk factors and co-medications, respectively. RESULTS: Mean follow-up duration was 30.91 ± 23.14 months in the entire group before adjustment. The ß-blockers group had a significantly higher incidence of new-onset DM and MACCE than the non-ß-blockers group. After PSM, analysis of a total of 2284 patients (1142 pairs, C-statistic = 0.752) showed no difference between the 2 groups in new-onset DM or MACCE. In multivariate analysis after PSM, baseline HbA1c, stroke, heart failure, nonselective ß-blockers, and age were independent predictors of new-onset DM. Selective ß1-blockers did not increase new-onset DM after adjustment for other antihypertensive medication and statins. CONCLUSIONS: In the era of newer ß-blockers, selective ß1-blockers were not associated with new-onset DM. More evidence is needed to verify this relationship and the underlying mechanisms.

Long-term clinical outcomes of catheter ablation in patients with atrial fibrillation predisposing to tachycardia-bradycardia syndrome: a long pause predicts implantation of a permanent pacemaker.

BACKGROUND: There is a controversy as to whether catheter ablation should be the first-line therapy for tachycardia-bradycardia syndrome (TBS) in patients with atrial fibrillation (AF). METHODS: We aimed to investigate long-term clinical outcomes of catheter ablation in patients with TBS and AF. Among 145 consecutive patients who underwent catheter ablation of AF with TBS, 121 patients were studied. RESULTS: Among 121 patients, 11 (9.1%) received implantation of a permanent pacemaker during a mean 21 months after ablation. Length of pause on termination of AF was significantly greater in patients who received pacemaker implantation after ablation than those who underwent ablation only (7.9 ± 3.5 vs. 5.1 ± 2.1 s, p < 0.001). Using a multivariate model, a long pause of 6.3 s or longer after termination of AF was associated with the requirement to implant a permanent pacemaker after ablation (HR 1.332, 95% CI 1.115-1.591, p = 0.002). CONCLUSION: This study suggests that, in patients with AF predisposing to TBS, long pause on termination of AF predicts the need to implant a permanent pacemaker after catheter ablation.

Korean atrial fibrillation network genome-wide association study for early-onset atrial fibrillation identifies novel susceptibility loci.

AIMS: Some genetic susceptibility loci for atrial fibrillation (AF) identified by genome-wide association studies (GWAS) in a European database showed ethnic differences in the Asian population. We explored novel AF susceptibility variants for patients with early-onset AF (≤60 years old) among Korean patients who underwent AF catheter ablation. METHODS AND RESULTS: A genome-wide association study (GWAS) was conducted with 672 cases (≤60 years old, Yonsei AF Ablation cohort) and 3700 controls (Korea Genome Epidemiology Study). Association analysis was performed under an additive model of logistic regression, and replication study was conducted with 200 independent cases of Korean AF Network and 1812 controls. Five previously proven genetic loci (1q24/PRRX1, 4q25/PITX2, 10q24/NEURL, 12q24/TBX5, and 16q22/ZFHX3) were validated. Two novel genetic loci associated with early-onset AF were found on chromosomes 1q32.1/PPFIA4 (rs11579055, P = 6.84 × 10-10) and 4q34.1/HAND2 (rs8180252, P = 1.49 × 10-11) and replicated in an additional independent sample of the Korean AF Network. The identified loci implicate candidate genes that encode proteins related to cell-to-cell connection, hypoxic status, or long non-coding RNA. CONCLUSION: Two novel genetic loci for early-onset AF were identified in Korean patients who underwent catheter ablation. One of the novel susceptibility loci on chromosome 4 has strong associations with previously proven gene in a European ancestry database.

Changes in Left Atrial Transport Function in Patients Who Maintained Sinus Rhythm After Successful Radiofrequency Catheter Ablation for Atrial Fibrillation: A 1-Year Follow-Up Multislice Computed Tomography Study.

BACKGROUND: Functional remodeling of left atrium (LA) after radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) has not been fully elucidated. This study aimed to determine the impact of RFCA on LA transport function in patients who maintained sinus rhythm (SR) after AF ablation. METHODS AND RESULTS: A total of 96 patients (paroxysmal AF [PAF] = 52) who maintained SR during 1 year after AF ablation were enrolled. Multislice computed tomography was performed to determine LA volume (LAV) and LA emptying fraction (LAEF) at pre-RFCA and 1-year post-RFCA. Creatine kinase-MB (CK-MB) and troponin-T levels were analyzed 1-day post-RFCA. At 1-year post-RFCA, mean LAV and LAEF decreased in overall patients. Based on LAEF change (ΔLAEF) cutoff of 5.0%, LAEF reduced in 41 patients (worsened group) and improved or showed no change in 55 patients (preserved group). Compared with preserved group, worsened group had a higher proportion of PAF, higher levels of CK-MB and troponin-T, and additional LA ablation. ΔLAEF was inversely correlated with CK-MB and troponin-T levels. Subgroup analysis showed that LAEF significantly decreased in PAF patients who underwent additional LA ablation. Multivariate analysis revealed that high baseline LAEF and additional LA ablation were independent predictors for worsened LAEF. CONCLUSIONS: Although SR was maintained for 1 year after AF ablation, LAEF as well as LAV decreased. The extent of LAEF deterioration was significantly associated with the amount of iatrogenic myocardial damage. Our data indicate that extensive atrial ablation may lead to LA functional deterioration, especially in patients with PAF.

Subclinical left ventricular diastolic dysfunction and incident type 2 diabetes risk: the Korean Genome and Epidemiology Study.

BACKGROUND: Subclinical left ventricular (LV) diastolic dysfunction in type 2 diabetes (T2D) is a common finding and represents an early sign of diabetic cardiomyopathy. However, the relationship between LV diastolic dysfunction and the incident T2D has not been previously studied. METHODS: A total of 1817 non-diabetic participants (mean age, 54 years; 48% men) from the Korean Genome and Epidemiology Study who were free of cardiovascular disease were studied. LV structure and function were assessed by conventional echocardiography and tissue Doppler imaging. Subclinical LV diastolic dysfunction was defined using age-specific cutoff limits for early diastolic (Em) velocity, mitral E/Em ratio, and left atrial volume index. RESULTS: During the 6-year follow-up period, 273 participants (15%) developed T2D. Participants with incident T2D had greater LV mass index (86.7 ± 16.4 vs. 91.2 ± 17.0 g/m2), worse diastolic function, reflected by lower Em velocity (7.67 ± 1.80 vs. 7.47 ± 1.70) and higher E/Em ratio (9.19 ± 2.55 vs. 10.23 ± 3.00), and higher prevalence of LV diastolic dysfunction (34.6 vs. 54.2%), compared with those who did not develop T2D (all P < 0.001). In a multivariate logistic regression model, lower Em velocity (odd ratio [OR], 0.867; 95% confidence interval [CI] 0.786-0.957) and the presence of LV diastolic dysfunction (OR, 1.617; 95% CI 1.191-2.196) were associated with the development of T2D, after adjusting for potential confounding factors. CONCLUSIONS: In a community-based cohort, the presence of subclinical LV diastolic dysfunction was a predictor of the progression to T2D. These data suggest that the echocardiographic assessment of LV diastolic function may be helpful in identifying non-diabetic subjects at risk of incident T2D.

Variants of Brugada Syndrome and Early Repolarization Syndrome: An Expanded Concept of J-Wave Syndrome.

BACKGROUND: The role of J-waves in the pathogenesis of ventricular fibrillation (VF) occurring in structurally normal hearts is important. METHODS: We evaluated 127 patients who received an implantable cardioverter-defibrillator (ICD) for Brugada syndrome (BS, n = 53), early repolarization syndrome (ERS, n = 24), and patients with unknown or deferred diagnosis (n = 50). Electrocardiography (ECG), clinical characteristics, and ICD data were analyzed. RESULTS: J-waves were found in 27/50 patients with VF of unknown/deferred diagnosis. The J-waves were reminiscent of those seen in BS or ERS, and this subgroup of patients was termed variants of ERS and BS (VEB). In 12 VEB patients, the J/ST/T-wave morphology was coved, although amplitudes were <0.2 mV. In 15 patients, noncoved-type J/ST/T-waves were present in the right precordial leads. In the remaining 23 patients, no J-waves were identified. VEB patients exhibited clinical characteristics similar to those of BS and ERS patients. Phenotypic transition and overlap were observed among patients with BS, ERS, and VEB. Twelve patients with BS had background inferolateral ER, while five ERS patients showed prominent right precordial J-waves. Patients with this transient phenotype overlap showed a significantly lower shock-free survival than the rest of the study patients. CONCLUSIONS: VEB patients demonstrate ECG phenotype similar to but distinct from those of BS and ERS. The spectral nature of J-wave morphology/distribution and phenotypic transition/overlap suggest a common pathophysiologic background in patients with VEB, BS, and ERS. Prognostic implication of these ECG variations requires further investigation.

Three-Year Major Clinical Outcomes of Angiography-Guided Single Stenting Technique in Non-Complex Left Main Coronary Artery Diseases.

There is limited long-term comparative clinical outcome data concerning angiography- versus intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) in non-complex left main coronary artery (LMCA) disease treated with the single stenting technique in the drug-eluting stent (DES) era.The aim of this study was to investigate whether angiography-guided stenting is comparable to IVUS-guided stenting during 3-year clinical follow-up periods in patients with non-complex LM disease treated with the single stenting technique.A total of 196 patients treated with either angiography-guided (n = 74) or IVUS-guided (n = 122) PCI were included. The primary outcome was the occurrence of major adverse cardiac events (MACE) defined as total death, non-fatal myocardial infarction (MI), target lesion revascularization (TLR), target vessel revascularization (TVR), and non-target vessel revascularization (Non-TVR). To adjust for any potential confounders, propensity score (PS) adjusted analysis was performed.During 3-year follow-up, the PS adjusted Cox-proportional hazard ratio (HR) was not significantly different between the two groups for total death, cardiac death, and MI. Also, TLR and the combined rates of TVR and non-TVR were not significantly different. Finally, MACE was not significantly different between the two groups (HR: 0.63, 95% Confidence interval (CI): 0.33-1.17; P = 0.149).Angiography-guided PCI for non-complex LMCA diseases treated with the single stenting technique showed comparable results compared with IVUS-guided PCI in reducing clinical events during 3-year clinical follow-up in the DES era. Although IVUS guided PCI is the ideal strategy, angiography-guided PCI can be an option for LMCA PCI in some selected cases.

Percutaneous Retrieval of Dislodged Left Atrial Appendage Occlusion Devices through the Transseptal Approach.

Percutaneous left atrial appendage (LAA) occlusion is a promising treatment option in patients with atrial fibrillation who have a high risk of embolic stroke and are not eligible for chronic oral anticoagulation therapy. This procedure, however, can induce several complications. Device embolization can result in a serious situation, requiring immediate and safe device removal. We report two cases in which dislodged LAA occlusion devices were flitting in the left atrium or entrapped in the mitral valve leaflets and were successfully retrieved through a transseptal approach without complications.

Interatrial septal thickness is associated with the extent of left atrial complex fractionated atrial electrograms and acute procedural outcome in patients with persistent atrial fibrillation.

AIMS: The interatrial septal thickness (IAST) reflects the changes of the atrial wall in patients with atrial fibrillation (AF). Complex fractionated atrial electrograms (CFAEs) were consistently positioned on the interatrial septum, especially in the remodelled left atrium (LA). We sought to characterize the relationship between IAST and LA CFAE area, as well as the acute procedural and clinical outcomes of catheter ablation in persistent AF patients. METHODS AND RESULTS: This study included 71 patients who underwent catheter ablation for drug-refractory persistent AF. A stepwise ablation approach included circumferential pulmonary vein isolation followed by LA and right atrial CFAE-guided ablation. Interatrial septal thickness was measured 1 cm inferior to the fossa ovalis on cardiac computed tomography (CT). The extent of LA CFAEs was assessed by CFAE area and index (CFAE area/LA surface area × 100). Patients were grouped into tertiles according to the value of IAST. The mean IAST of the first, second, and third tertile was 4.69 ± 0.79, 6.44 ± 0.45, and 9.12 ± 1.42 mm, respectively (P < 0.001). The mean CFAE areas (5.6 ± 6.9, 18.5 ± 20.3, and 24.3 ± 26.6 mm(2), P = 0.005) and CFAE indexes (3.1 ± 4.2, 9.2 ± 10.7, and 11.8 ± 15.3, P = 0.025) in LA were significantly different among the three groups. More patients in the highest IAST tertile did not terminate AF during catheter ablation (12.5% vs. 26.1% vs. 37.5%, P = 0.048). CONCLUSIONS: Interatrial septal thickness measured by cardiac CT is associated with the extent of CFAE area within the LA and is related to acute procedural success of catheter ablation. These findings suggest that IAST reflects the degree of atrial substrate and remodelling in patients with persistent AF.

Gap junction remodelling by chronic pressure overload is related to the increased susceptibility to atrial fibrillation in rat heart.

AIMS: Left atrial (LA) fibrosis caused by various pathological stimuli is a common finding. However, the difference of atrial remodelling via haemodynamic change in diverse cardiomyopathy has not been elucidated. METHODS AND RESULTS: Male Sprague-Dawley rats (6-8 weeks, n = 180) were randomly assigned to three groups and corresponding sham control groups: (i) ischaemic cardiomyopathy, (ii) left ventricular hypertrophy (LVH), and (iii) dilated cardiomyopathy. At 12 weeks after operation, atrial fibrillation (AF) inducibility and duration were assessed by in vivo burst transoesophageal pacing. Using the Langendorff apparatus, left ventricular (LV) function and pressure were measured. The expression of connexin-43 (Cx43) and alpha-smooth muscle actin (α-SMA) in atrial tissues was assessed by quantitative real-time polymerase chain reaction and immunohistochemical staining. Fibrosis was analysed by Masson's trichrome staining. Compared with controls, the LA weight/heart weight ratio was increased in the LVH group alone, and was significantly correlated with AF duration (P < 0.001, R = 0.388). Atrial fibrillation inducibility and duration were higher and longer only in the LVH group (P = 0.002, 0.079, respectively), and isolated LV diastolic dysfunction and elevated LV pressure were observed. Although α-SMA expression and fibrosis were increased in all three cardiomyopathy models, down-regulation of Cx43 expression in the LA was observed in the LVH group alone. CONCLUSION: Chronic pressure overload in the absence of LV systolic dysfunction resulted in LA hypertrophy and increased susceptibility to AF, which might be related to conduction abnormality via decreased expression and lateral distribution of Cx43 as well as interstitial fibrosis.