Larger Left Atrial Research Articles

BI-ATRIAL MAPPING AND ELEVATED HEART RATES IDENTIFY ABNORMAL ATRIAL SUBSTRATE IN ATRIAL FIBRILLATION PATIENTS WITHOUT LOW-VOLTAGE AREAS IN THE LEFT ATRIUM

BI-ATRIAL MAPPING AND ELEVATED HEART RATES IDENTIFY ABNORMAL ATRIAL SUBSTRATE IN ATRIAL FIBRILLATION PATIENTS WITHOUT LOW-VOLTAGE AREAS IN THE LEFT ATRIUM

Association of ZFHX3 genetic polymorphisms and extra-pulmonary vein triggers in patients with atrial fibrillation who underwent catheter ablation

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Health and Welfare, National Research Foundation of Korea (NRF) Abstract Background The ZFHX3 gene (16q22) is the second most highly associated gene with atrial fibrillation (AF) and is related to inflammation and fibrosis. Purpose We hypothesized that ZFHX3 is associated with extra-pulmonary vein (PV) triggers, left atrial (LA) structural remodeling, and poor rhythm outcomes of AF catheter ablation (AFCA). Methods We included 1782 patients who underwent a de novo AFCA (73.5% male, 59.4±10.8 years old, 65.9% paroxysmal AF) and genome-wide association study and divided them into discovery (n=891) and replication cohorts (n=891). All included patients underwent isoproterenol provocation tests and LA voltage mapping. We analyzed the ZFHX3, extra-PV trigger-related factors, and rhythm outcomes. Results Among 14 single-nucleotide polymorphisms (SNPs) of ZFHX3, rs13336412, rs61208973, rs2106259, rs12927436, and rs1858801 were associated with extra-PV triggers. In the overall patient group, extra-PV triggers were independently associated with the ZFHX3 polygenic risk score (PRS) (OR 1.65 [1.22-2.22], p=0.001, model 1) and a low LA voltage (OR 0.74 [0.56-0.97], p=0.029, model 2). During 49.9±40.3 months of follow-up, clinical recurrence of AF was significantly higher in patients with extra-PV triggers (Log-rank p<0.001, HR 1.89 [1.49-2.39], p<0.001, model 1), large LA dimensions (Log-rank p<0.001, HR 1.03 [1.01-1.05], p=0.002, model 2), and low LA voltages (Log-rank p<0.001, HR 0.73 [0.61-0.86], p<0.001, model 2) but not the ZFHX3 PRS (Log-rank p=0.819). Conclusions The extra-PV triggers had significant associations with both ZFHX3 genetic polymorphisms and acquired LA remodeling. Although extra-PV triggers were an independent predictor of AF recurrence after AFCA, the studied AF risk SNPs intronic in ZFHX3 were not associated with AF recurrence.

Association of ZFHX3 Genetic Polymorphisms and Extra-Pulmonary Vein Triggers in Patients With Atrial Fibrillation Who Underwent Catheter Ablation.

Background: The ZFHX3 gene (16q22) is the second most highly associated gene with atrial fibrillation (AF) and is related to inflammation and fibrosis. We hypothesized that ZFHX3 is associated with extra-pulmonary vein (PV) triggers, left atrial (LA) structural remodeling, and poor rhythm outcomes of AF catheter ablation (AFCA).Methods: We included 1,782 patients who underwent a de novo AFCA (73.5% male, 59.4 ± 10.8 years old, 65.9% paroxysmal AF) and genome-wide association study and divided them into discovery (n = 891) and replication cohorts (n = 891). All included patients underwent isoproterenol provocation tests and LA voltage mapping. We analyzed the ZFHX3, extra-PV trigger-related factors, and rhythm outcomes.Result: Among 14 single-nucleotide polymorphisms (SNPs) of ZFHX3, rs13336412, rs61208973, rs2106259, rs12927436, and rs1858801 were associated with extra-PV triggers. In the overall patient group, extra-PV triggers were independently associated with the ZFHX3 polygenic risk score (PRS) (OR 1.65 [1.22–2.22], p = 0.001, model 1) and a low LA voltage (OR 0.74 [0.56–0.97], p = 0.029, model 2). During 49.9 ± 40.3 months of follow-up, clinical recurrence of AF was significantly higher in patients with extra-PV triggers (Log-rank p < 0.001, HR 1.89 [1.49–2.39], p < 0.001, model 1), large LA dimensions (Log-rank p < 0.001, HR 1.03 [1.01–1.05], p = 0.002, model 2), and low LA voltages (Log-rank p < 0.001, HR 0.73 [0.61–0.86], p < 0.001, model 2) but not the ZFHX3 PRS (Log-rank p = 0.819).Conclusion: The extra-PV triggers had significant associations with both ZFHX3 genetic polymorphisms and acquired LA remodeling. Although extra-PV triggers were an independent predictor of AF recurrence after AFCA, the studied AF risk SNPs intronic in ZFHX3 were not associated with AF recurrence.

The Progression of Atrial Substrate in Patients with Recurrent Left Atrial Ablation Procedures

Larger left atrial (LA) size and the presence of LA scar are associated with worse outcomes following AF ablation. Patterns of scar and its progression over time on electroanatomic maps (EAMs) have not been previously characterised.

Obesity in Older Adults and Associations with Cardiovascular Structure and Function

Introduction: Body mass index (BMI), despite being widely used as a marker of obesity, fails to fully capture cardiovascular risks as it is an insufficient biomarker of abdominal adiposity, unlike waist circumference (WC). We aimed to characterize associations between BMI and WC with cardiovascular structure and function in older adults. Methods: Among an observational cohort study of a community of older adults, transthoracic echocardiography determined cardiovascular structure and function, while aerobic capacity was determined by peak oxygen uptake (VO₂) metrics. The cut-offs for obesity were 27.5 kg/m² for BMI, and >90 cm for males and >80 cm for females for WC. Results: Of 970 older adults without cardiovascular disease (mean age 73 ± 4 years, 432 [44%] males), 124 (12.8%) were obese by BMI definition while 347 (35.7%) were obese by WC definition. Inter-definitional agreement was fair (Cohen’s κ = 0.345). Unlike the BMI definition, participants defined as obese by WC were more likely to be women (65% vs. 50%, p < 0.001), older (65 ± 11 vs. 63 ± 14 years, p = 0.007), and had lower handgrip strength (24 ± 0.6 vs. 26 ± 0.4 kg, p = 0.022). Across BMI categories, high WC was associated with more impaired myocardial relaxation (E/A), and VO₂ measurements (all p < 0.05). Among those with low BMI, high WC was associated with larger left atrial (LA) volumes (p = 0.003). WC, but not BMI, was independently associated with E/A (β = −0.114, SE −0.114 ± 0.024, p < 0.001) in regression analysis. Conclusion: WC identified a higher prevalence of obesity, possibly related to central adiposity. Across BMI categories, WC identified more adverse measurements in E/A, aerobic capacity, and LA structure. Trial Registration: ClinicalTrials.gov Identifier: NCT02791139.

The Prevalence of Left Atrial Appendage Thrombus in Patients on Anticoagulation Undergoing TOE-DCR and Their Echocardiographic Parameters

The prevalence of left atrial (LA)/atrial appendage (LAA) thrombus in patients with atrial fibrillation/atrial flutter on anticoagulation and the echocardiographic parameters to delineate risk is unknown. The aim of this study was to assess the thrombus prevalence in patients on anticoagulation and their echocardiographic parameters. We retrospectively assessed patients who presented for transoesopheageal echocardiogram guided direct cardioversion at a single centre from 2016 to 2022. 500 patients were included in the analysis. The prevalence of LAA thrombus was 4.8%. The patient characteristics and echocardiographic parameters are listed in the Table. LA thrombus rate was higher in patients with systolic dysfunction, large LA size, spontaneous echo contrast (SEC) and low LAA velocity. There was no significant difference in prevalence of thrombus based on type of anticoagulation, ie, NOAC or warfarin. Despite oral anticoagulation, LAA thrombus is prevalent in patients with AF. Routine usage of TOE is vital especially in high-risk patient groups.Tabled 1Pts with LA/LAA thrombus (n=24)Pts without LA/LAA thrombus (n=476)Age68.2 ± 8.270.4 ± 10.6M:F17:7335:144AF/A. Flutter24/0408/65Mean LAA velocity (m/sec)0.260.33Mean LA size (mL/m2)42.534.9Mean LVEF42% ± 11.5%48% ± 12%SEC10 (42%)60 (13%)Anticoagulant:Apixaban11 (46%)202 (42%)Rivaroxaban7 (29%)205 (43%)Dabigatran016 (3.4%)Warfarin2 (8.3%)41 (8.6%)CHADSVASC 0-17 (29%)99 (21%)CHADSVASC ≥216 (67%)367 (56%) Open table in a new tab

Clinical Outcomes of low-voltage area-guided left atrial linear ablation for non-paroxysmal atrial fibrillation patients

BackgroundThe therapeutic effect of low-voltage area (LVA)-guided left atrial (LA) linear ablation for non-paroxysmal atrial fibrillation (non-PAF) is uncertain. We aimed to investigate the efficacy of LA linear ablation based on the preexisting LVA and its effects on LA reverse remodeling in non-PAF patients.MethodsWe retrospectively evaluated 145 consecutive patients who underwent radiofrequency catheter ablation for drug-refractory non-PAF. CARTO-guided bipolar voltage mapping was performed in atrial fibrillation (AF). LVA was defined as sites with voltage ≤ 0.5 mV. If circumferential pulmonary vein isolation couldn’t convert AF into sinus rhythm, additional LA linear ablation was performed preferentially at sites within LVA.ResultsAfter a mean follow-up duration of 48 ± 33 months, 29 of 145 patients had drugs-refractory AF/LA tachycardia recurrence. Low LA emptying fraction, large LA size and high extent of LVA were associated with AF recurrence. There were 136 patients undergoing LA linear ablation. The rate of linear block at the mitral isthmus was significantly higher via LVA-guided than non-LVA-guided linear ablation. Patients undergoing LVA-guided linear ablation had larger LA size and higher extent of LVA, but the long-term AF/LA tachycardia-free survival rate was higher than the non-LVA-guided group. The LA reverse remodeling effects by resuming sinus rhythm were noted even in patients with a diseased left atrium undergoing extensive LA linear ablation.ConclusionsLVA-guided linear ablation through targeting the arrhythmogenic LVA and reducing LA mass provides a better clinical outcome than non-LVA guided linear ablation, and outweighs the harmful effects of iatrogenic scaring in non-PAF patients.

Abstract 14335: Abnormal Left Atrial Conduit Function in Obstructive Hypertrophic Cardiomyopathy is Mediated Through Elevated Left Ventricular Filling Pressure

Introduction: Elevated left ventricular outflow tract (LVOT) gradient occurs in a majority of HCM patients and is associated with diastolic dysfunction, heart failure, atrial fibrillation and death. These adverse outcomes are also commonly associated with Left atrial (LA) dysfunction. Yet, the nature and extent of the relationship between LVOT gradient and LA function remains ill-understood. Methods: HCM patients were classified as obstructive (rest gradient ≥ 30 mmHg), labile (rest gradient &lt; 30 mmHg, provoked gradient ≥ 30 mmHg) and non-obstructive (rest and provoked gradient &lt; 30 mmHg). In addition to conventional analysis, LA reservoir, conduit and contractile strain were measured (TomTec Imaging Systems). Results: Of 135 patients, 34 (44% male) were obstructive, 36 (75% male) labile and 65 (63% male) non-obstructive HCM. Large LA volume index and elevated E/e’ was associated with elevated LVOT gradient at rest (r 0.17; p 0.04 and r 0.40; p&lt;0.001, respectively) and with Valsalva (r 0.19; p 0.03 and r 0.33; p&lt;0.001, respectively). Low LV strain was associated with elevated LVOT gradient with exercise (r -0.22, p 0.04). LA conduit strain (but not reservoir or contractile strain) was lower in patients with obstructive HCM compared to patients with non-obstructive HCM (13.1 ± 5.4 vs 11.0 ± 3.9%, p = 0.03, Figure 1). There was no significant difference in all LA strain parameters across all the other HCM types. Conclusions: Measures of elevated LV filling pressure (large LA volume index, elevated E/e’ and low LV strain) were associated with elevated LVOT gradient. LA conduit strain was lower in obstructive compared to non-obstructive HCM. Our data suggest that elevated LVOT gradient is associated with abnormal LA conduit function most likely mediated via elevated LV filling pressure.

Cardiac metastasis of triple-negative breast cancer mimicking myxoma: A case report.

IntroductionMetastatic heart tumors are rare, occurring in 1.5–20% of cancer patient autopsies. Lymphoma, melanoma, leukemia, and carcinomas of the lung, esophagus, and breast are the most prevalent causes of these metastases, although they can originate from any malignant tumor. Here we report a case of triple-negative breast cancer with cardiac metastasis mimicking myxoma.Presentation of caseA 39-year-old woman presented at the emergency department with shortness of breath. Vital signs were hypotension and tachypnea. There were coarse crackles at the bases of both lungs. Electrocardiography results showed a normal sinus rhythm. Chest X-ray revealed cardiomegaly with signs of pulmonary edema. Echocardiography revealed a large left atrial (LA) mass protruding to the mitral valve and attached to the interatrial septum during diastole. The patient was diagnosed with cardiogenic shock, acute kidney injury, elevated liver enzymes, and an LA mass. Surgical excision through median sternotomy was planned. Intraoperatively, an LA mass was found. The histopathology evaluation showed an LA mass with invasive ductal carcinoma of metastatic breast tumors. Immunohistochemistry (IHC) confirmed the diagnosis of triple-negative breast cancer that had metastasized to the heart. Postoperative echocardiography confirmed complete excision of the tumor.DiscussionBreast cancer that has metastasized to the heart is uncommon. This patient was referred to the surgical oncology section for the treatment of triple-negative breast cancer with cardiac metastasis.ConclusionA heart mass should be suspected of having metastasized if the patient has a history of malignancy, even if it occurred several years earlier.

A potential misdiagnosis in the COVID-19 pandemic era: a case report of superimposed thrombosis or tumor recurrence

BackgroundThe clinical manifestations of coronavirus disease 2019 (COVID-19) overlap with those of other disorders, especially cardiovascular disease.Case presentationWe herein describe a 58-year-old woman who presented with syncopal episodes and dyspnea on exertion with a left atrial (LA) mass, scheduled for surgical removal and mitral valve replacement. Nearly 3 months later, the patient developed dyspnea, fever, and a sore throat, resulting in hospital admission with suspected COVID-19. During the diagnostic evaluation, a larger LA mass was detected. The mass seemed to be a COVID-19–induced organized thrombus with prosthetic mitral valve malfunction. Resection was, therefore, planned. An immunohistochemistry study revealed a liposarcoma.ConclusionsThe unusual early recurrence of liposarcomas and the misdiagnosis with COVID-19–induced thrombosis are the hallmark of the present case.

Comparing echocardiographic characteristics in genotype positive-phenotype positive hypertrophic cardiomyopathy and hypertensive left ventricular hypertrophy.

There is little information about hypertrophic cardiomyopathy (HCM) with pathologic genetic mutations and concurrent hypertension (HTN). Hypertensive left ventricular hypertrophy (LVH) does not exclude an underlying genetic aetiology. This was a single-centre case-control study of 39 adults with pathologic HCM mutations, confirmed by genetic testing, compared to 39 age- and gender-matched patients with hypertensive LVH. The gene-positive HCM cohort was further stratified by the coexisting presence or absence of HTN. Clinical and echocardiographic characteristics were compared. Of 39 gene-positive HCM, 43.6% (17/39) had concurrent HTN. The gene-positive HCM cohort had larger left atrial (LA) area (22.1 cm2 vs. 18.9 cm2, P = 0.002), more diastolic predominant pulmonary vein flow (38.5% vs. 7.7%, P = 0.001), and more moderate diastolic dysfunction (33.3% vs. 12.8%, P = 0.032) when compared with the hypertensive LVH cohort. Greater left ventricular (LV) mass (277.7 g vs. 207.7 g, P = 0.025), increased frequency of severe LVH (58.8% vs. 27.3%, P = 0.047), and more abnormal global longitudinal strain (GLS) (-14.1% vs. -16.9%, P = 0.049) was observed in the gene-positive HCM cohort with concurrent HTN. Gene-positive HCM, compared to hypertensive LVH, is characterized by more advanced diastolic dysfunction and larger LA size. Gene-positive HCM patients with concomitant HTN had greater LV mass, more severe LVH, and more abnormal GLS, suggesting HTN may negatively affect the progression of myocardial dysfunction in genetic HCM. LVH out-of-proportion to pressure burden in HTN patients should raise suspicion of underlying genetic HCM.

GJA1 Expression and Left Atrial Remodeling in the Incidence of Atrial Fibrillation in Patients with Obstructive Sleep Apnea Syndrome.

Obstructive sleep apnea syndrome (OSAS) is an important risk factor for atrial fibrillation (AF). GJA1 gene encoding connexin43, a major protein in cardiac gap junctions, plays a crucial role in the synchronized contraction of the heart and in cardiac arrhythmia. However, little is known regarding the role of GJA1 expression in the incidence of AF in patients with OSAS. All prospectively enrolled OSAS patients underwent polysomnography, electrocardiography, a 24-h Holter test, and echocardiography. Moderate-to-severe OSAS was defined as an apnea-hypopnea index (AHI) ≥ 15. Exosomes were purified from the plasma of all OSAS patients and incubated in HL-1 cells to investigate the effect of exosomes from patients with and without AF on GJA1 expression. A total of 129 patients were recruited for this study; 26 were excluded due to an AHI < 15. Of the 103 enrolled patients, 21 had AF, and 82 did not. Multivariate analysis showed diabetes mellitus, lower sleep efficiency, lower left ventricular ejection fraction, and larger left atrial (LA) size were independent predictors of AF occurrence in OSAS patients. The area under the receiver operating characteristic curve for LA with a size ≥38.5 mm for predicting AF occurrence in OSAS patients was 0.795 (95% confidence interval [0.666, 0.925]); p < 0.001). GJA1 expression in HL-1 cells incubated with exosomes from OSAS patients with AF was lower than that with exosomes from patients without AF after controlling for age and sex and was negatively correlated with the AHI and oxygen desaturation index (ODI), especially during the non-rapid eye movement period (NREM) of OSAS patients with AF (all p < 0.05). LA size was an independent predictor of AF occurrence in OSAS patients. The AHI and ODI in the NREM period of OSAS patients with AF were negatively correlated with GJA1 expression in HL-1 cells, which offers a hint that GJA1 may play a crucial role in the development of AF in patients with OSAS.

Genetic polymorphisms of interleukin-6 and interleukin-10 are not associated with new onset atrial fibrillation after coronary artery bypass graft surgery

Abstract Purpose To estimate the association of the genetic polymorphisms of Interleukin-6 (IL-6) and Interleukin-10 (IL-10) with new onset atrial fibrillation (AF) in postoperative period of coronary artery bypass graft (CABG) surgery in patients with coronary artery disease (CAD). Methods Studied were 158 patients who underwent CABG. In all the patients routine laboratory and instrumental tests were performed. Patients also underwent genetic polymorphisms of IL-6 C174G, IL-10 C592A and IL-10 G1082A estimation. All the patients were divided into two groups: 1 group comprised 111 patients without AF (82.0% men, median age 62.0 (56.0; 66.0) years, 2 group - 47 patients with AF development after CABG (84.4% men, median age 65.0 (61.0; 70.0) years). Results During the observation period AF occurred in 29.7% patients, on average 5.2 (2.0; 7.0) days after surgery. Patients of group 2 had longer history of CAD (60.0 (13.5; 138.0) vs. 15.5 (8.0; 72.0) months, p=0.01), had more often NYHA III class (27.7% vs. 9.0%, p=0.002) and larger left atrial (LA) diameter (44.0 (40.5; 46.0) mm vs. 38.0 (36.0; 40.0) mm, p&amp;lt;0.0001) comparing with group 1. Genotype CC IL-6 C174G was found in 19.8% patients of the 1 group and in 25.5% patients of the 2 group (p=0.42), genotype CG - in 56.8% and 53.2% (p=0.68), genotype GG - in 23.4% and 21.3% (p=0.77) respectively. Genotype CC IL-10 C592A was found in 62.2% patients of the 1 group and 46.8% patients of the 2 group (p=0.29), genotype CA - in 37.8% patients of the 1 group and in 53.2% patients of the 2 group (p=0.07) respectively. Genotype GG IL-10 G1082A was found in 25.2% patients of the 1 group and 23.4% patients of the 2 group (p=0.8), genotype GA - in 48.6% patients of the 1 group and in 59.6% patients of the 2 group (p=0.2), genotype AA - in 26.2% patients of the 1 group and in 17.0% patients of the 2 group (p=0.3) respectively. All estimated genotypes fulfilled expectations of Hardy-Weinberg equilibrium. According to the result of multivariate regression analysis the odds ratio for AF development in postoperative period of CABG for history of CAD more than 20 months - 1.1 (95% CI, 1.03–1.2, p=0.04), for LA dimension more than 41 mm - 1.5 (95% CI, 1.28–1.79, p&amp;lt;0.0001). Conclusion Our investigation showed that increased left atrial dimension and the history of coronary artery disease were associated with postoperative atrial fibrillation development in patients who underwent coronary artery bypass graft surgery. However, genetic polymorphisms of IL-6 C174G, IL-10 C592A and IL-10 G1082A were not significantly associated with postoperative atrial fibrillation development. Funding Acknowledgement Type of funding sources: None.

The prevalence and characteristics of candidates for percutaneous left atrial appendage occlusion using a WATCHMAN device among patients who underwent atrial fibrillation ablation in a Japanese population.

Percutaneous left atrial appendage occlusion (LAAO) using a WATCHMAN device could be a treatment option for patients with non-valvular atrial fibrillation (AF) with thromboembolic and bleeding risk. We sought to determine the prevalence and characteristics of patients with AF ablation who are potential candidates for WATCHMAN implantation in a Japanese population. We enrolled 2443 consecutive patients who had previously undergone AF ablation and transesophageal echocardiography (TEE). We assessed their clinical characteristics and measured their LAA orifice diameter and depth retrospectively using the obtained TEE images. We defined patients who met both anatomical criteria (LAA orifice max diameter: 17-31mm and LAA max depth > LAA orifice max diameter) and clinical criteria (CHA2DS2-VASc score ≥ 2 and HAS-BLED score ≥ 3) as LAAO candidates. Among the 2443 enrolled patients, 361 (15%) met the clinical criteria, and 1928 (79%) met the anatomical criteria. Thus 12% (293/2443) of the total patient group met the criteria of LAAO candidates. LAAO candidates showed larger left atrial (LA) volume (77.6 ± 30.1 vs. 67.7 ± 29.1mL, P < 0.001), larger LAA orifice diameter (22.5 ± 3.2 vs. 22.0 ± 4.3mm, P = 0.026), and larger LAA depth (28.9 ± 4.6 vs. 27.0 ± 4.8mm, P < 0.001). LAAO candidates made up only 23% of patients with CHA2DS2-VASc score ≥ 2 (N = 1295), whereas 78% of patients with a HAS-BLED score ≥ 3 (N = 378) were LAAO candidates. Twelve percent of patients who underwent AF ablation were potential candidates for LAAO using a WATCHMAN device in this Japanese population. It is imperative to evaluate bleeding risk when considering the indications for LAAO.

Long-term outcomes of empirical extra-pulmonary vein linear ablation in patients with persistent atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was supported by grants [HI18C0070] and [HI19C0114] from the Korea Health 21 R&amp;D Project, Ministry of Health and Welfare, and a grant [NRF-2020R1A2B01001695] from the Basic Science Research Program run by the National Research Foundation of Korea (NRF). Background Although extra-pulmonary vein (PV) left atrial (LA) linear ablation has been performed during catheter ablation (CA) of persistent atrial fibrillation (PeAF), the long-term efficacy and safety of this procedure have not yet been verified. Purpose We investigated whether an anterior line (AL) and posterior box ablation (POBA) in addition to circumferential PV isolation (CPVI) improves the rhythm without worsening the LA function in PeAF patients. Methods We retrospectively compared the additional AL + POBA and CPVI alone groups in 604 patients with PeAF who underwent regular rhythm follow-ups (16.9%; males 79.3%, 58.5 ± 10.7 years of age) after propensity score matching. The primary endpoint was AF recurrence after single procedures and secondary endpoints were the cardioversion rate, response to anti arrhythmic drugs, LA changes, and re-conduction rates of the de-novo ablation lesion set. Results After a mean follow-up of 45.2 ± 33.6 months, the clinical recurrence rate did not significantly differ between the two groups (log-rank p = 0.554) despite longer procedure times in the AL + POBA group (p &amp;lt; 0.001). Atrial tachycardia recurrences (p = 0.001) and the cardioversion rates after ablation (p &amp;lt; 0.001) were higher in the AL + POBA group than CPVI group. AL + POBA was associated with better rhythm outcomes in patients with large anterior LA volume indices (p for interaction 0.037) and low mean LAA(left atrial appendage) voltages (p for interaction 0.019). In repeat procedures, the LA pulse pressure elevation was significant after the AL + POBA. Conclusion In patients with PeAF, an AL + POBA in addition to the CPVI did not improve the rhythm outcomes nor influence the long-term safety, and lead to more extended procedures. Procedure outcomes OverallAL + POBACPVIp-value(n = 604)(n = 302)(n = 302)Procedure time, min190.8 ± 62.6226.9 ± 49.4154.6 ± 52.8&amp;lt;0.001Ablation time, sec5079 ± 19566420 ± 13723738± 1475&amp;lt;0.001Overall complications24 (4.0)13 (4.3)11 (3.6)0.835Early recurrence, n (%)277 (45.9)129 (42.7)148 (49.0)0.142Recurrence type AT, n (% in early recur)77 (27.8)51 (39.5)26 (17.6)&amp;lt;0.001Clinical recurrence within 1-year, n(%)116 (19.2)52 (17.2)65 (21.5)0.256Recurrence type AT, n (% in clinical recur)60 (23.1)46 (30.7)14 (12.7)0.001Cardioversion, n (% in total recur/ % overall)105 (40.4/17.4)74 (49.3/24.5)31 (28.1/10.3)&amp;lt;0.001POBA, posterior box ablation; AL, anterior line; CPVI, circumferential pulmonary vein isolation; AT, atrial tachycardia;Abstract Figure. Long term ablation outcome

Effect of Renal and Left Ventricular Function on Serial Pulmonary Arterial Pressure Changes after Device Closure of Atrial Septal Defect.

Background The age of candidates for device closure of atrial septal defect (ASD) has been increasing. Thus, concerns exist about dyspnea aggravation or atrial fibrillation development after device closure due to augmentation of left ventricular (LV) and left atrial (LA) preload. This study aimed to examine patterns and determinants of serial pulmonary arterial pressure and left ventricular filling pressure changes after device closure of ASD. Methods Among the 86 consecutive patients who underwent percutaneous device closure of ASD, those with end-stage renal disease or those without pre- or postprocedural Doppler data were excluded. The clinical, transesophageal, and transthoracic echocardiographic findings of 78 patients were collected at baseline, one-day postprocedure, and one-year follow-up. Results The mean age of study patients was 49.8 ± 15.0 years, and the average maximal defect diameter and device size were 20.2 ± 6.0 mm and 23.8 ± 6.4 mm. Four patients (5.6%) underwent new-onset atrial fibrillation, and five patients (6.4%) took diuretics within one-year after closure. Some patients (n = 21; 27%) exhibited paradoxically increased tricuspid regurgitant velocity (TRV) one-day postprocedure; they also were older with lower e', glomerular filtration rate, and LV ejection fraction and a higher LA volume index. However, even in these patients, TRV deceased below baseline levels one-year later. Both E/e' and LA volume index significantly increased immediately after device closure, but all decreased one-year later. Larger defect size and higher TRV were significantly correlated with immediate E/e' elevation. Conclusion In older, renal, diastolic, and systolic dysfunctional patients with larger LA and scheduled for larger device implantation, peri-interventional preload reduction therapy would be beneficial.

Altered Expression of Circadian Clock Genes in Patients with Atrial Fibrillation Is Associated with Atrial High-Rate Episodes and Left Atrial Remodeling.

A prominent circadian variation is present in atrial fibrillation (AF) attacks that may be related to the expression of circadian clock genes. Little is known about the expression of circadian clock genes in AF. We prospectively enrolled 73 patients who had received pacemaker implantation, in order to define the burden of atrial high-rate episodes (AHREs) accurately. AF was diagnosed clinically in 43 (59%) patients (15 with persistent AF and 28 with paroxysmal AF). The expression levels of circadian clock genes of peripheral blood leukocytes were checked. There were more males and patients with a larger left atrial (LA) size and lower expression levels of BMAL1, CRY2, NR1D1, NR1D2, PER2, RORA, RORC, and TIM genes in persistent AF group than in other groups. There was a significant correlation between higher AHRE burden and larger LA size and between higher AHRE burden and decreased expression of circadian clock genes in patients with AF. LA volume and the expression of CRY1, NR1D1, and RORA are significantly associated with AHRE burden. However, the underlying mechanism needs to be elucidated in further studies.

Abstract 14520: Differences in Left Atrial Size and Function and Supraventricular Arrhythmias Between Blacks and Whites in the Atherosclerosis Risk in Communities (ARIC) Study: Implications for AF Pathogenesis

Introduction: Black Americans have more atrial fibrillation (AF) risk factors but lower AF risk than whites. Left atrial (LA) enlargement, impaired LA function, frequent premature atrial contractions (PAC), and atrial tachycardia (AT) are risk factors for AF. Racial differences in LA size and function, PAC, or AT may exist that could explain the difference in AF risk. Hypothesis: Whites have higher PAC and AT frequency than blacks. Additionally, whites have larger LA size and lower LA function than blacks, which may contribute to the racial difference in AF. Methods: We included 1,623 ARIC participants free of AF who had 2D-echocardiograms at visit 5 (2011-2013) and wore a 2-week continuous heart monitor, the Zio ® XT Patch, at visit 6 (2016-2017). Weighted linear regression was used to analyze the association of race with LA size and function, as well as runs of AT per day and PAC per hour. Results: At visit 5, participants were 74 (4) years old, 58% were female, and 26% were black. AT runs were detected in 87% of blacks and 92% of whites, respectively (p=0.002). Among participants with &gt;0 runs of AT per day (n=1480), blacks had 48% (95% CI: 21%-66%) fewer runs of AT per day than whites after adjustment for cardiovascular (CV) risk factors † . There was no significant difference in PAC frequency between blacks and whites. After adjusting for age and sex, blacks had greater LA size and lower LA function than whites; these differences attenuated after adjusting for CV risk factors (Table). Conclusion: Blacks have greater age and sex-adjusted abnormality in LA size and function than whites, likely due to higher prevalence of CV risk factors. Yet, blacks have lower propensity for AT. More research is needed to elucidate the mechanisms underlying the resistance to atrial arrhythmogenesis in blacks despite greater adverse LA remodeling.

Predictors of postoperative atrial fibrillation after coronary artery bypass grafting: a prospective observational cohort study

BackgroundThis study was conducted to determine the effect of certain predictors on the incidence of postoperative atrial fibrillation (POAF) during ICU stay after coronary artery bypass graft (CABG) surgery.ResultsWe enrolled 123 patients in this study. The mean age was 57.4 ± 8.7 years, and the mean left atrial diameter was 4.1 ± 0.52 cm with male preponderance (76.4%). The incidence of POAF following CABG was 33.3%. There was no statistically significant association between POAF and smoking (P = 0.123). However, POAF was significantly associated with higher CHA2DS2-VASc score (P = 0.002), valve replacement (P < 0.001), and inotropic support (P = 0.005). Moreover, patients with POAF had significantly higher mean age (P = 0.031) and left atrial (LA) diameter (P < 0.001). Logistic regression showed that LA diameter (P < 0.001), potassium level at 36 h (P = 0.016), and female gender (P = 0.001) were independent predictors of POAF.ConclusionsWe had several significant epidemiological, clinical, and operative variables that were significantly associated with post-CABG AF, including older age, female gender, large LA diameter, valve replacement, higher CHA2DS2-VASc score, and postoperative inotropic support. However, only LA diameter, female gender, and potassium level at 36 h were independent predictors of POAF. Nevertheless, further large-scale studies are needed to confirm our findings.

Predictors of silent cerebral infarction associated with catheter ablation for atrial fibrillation

Abstract Introduction Cather ablation (CA) has been identified as an effective and safe treatment option for patients with atrial fibrillation (AF). One of the serious complications associated AF is cerebral infarction (CI). Recent studies reported that CA was associated with lower incidence of ischemic stroke in patients with AF. However, CA for AF itself has a potential risk of CI. Several previous studies showed that the incidence of silent CI (SCI) assessed by magnetic resonance imaging (MRI) of the brain occurred 5 to 18% during CA for AF. Recently, CA for AF made a remarkable progress in technology. However, there are few information available that the impact of 3-dimensional electroanatomical mapping system on the incidence of SCI. This study aimed to clarify the prevalence and predictors of SCI during CA for AF. Methods We enrolled 893 consecutive patients (male 534, age 71±10 years), who underwent CA for AF and MRI of brain 1 day after the procedure. We collected patients data such as physical examinations, blood sampling, echo cardiography, and CA data. A brain MRI was performed the next day following the procedure to identify any CIs. One-hundred and forty-six of patients used the Rhythmia® mapping system catheter, and the other mapping system such as CARTO or EnSite system used in the remaining 747 patients. Results The MRI depicted acute micro-CIs in 144 (16%) patients, but neither symptoms nor abnormal neurological findings were present in these patients. Patients with SCI had significantly higher prevalence of persistent AF (60 vs 43%, p=0.0002), CHADS2 Score (2 (1–3) vs 1 (1–2), p=0.0001), higher prevalence of previous stroke (19 vs 12%, p=0.02), larger left atrial (LA) diameter (43.2±6.4 vs 41.7±6.5mm, p=0.01), lower left ventricular ejection fraction (LVEF) (59.0±13.2 vs 64.2±11.3%, p≤0.0001), higher B-type natriuretic peptide level (221±236 vs 163±225 pg/dl, p≤0.0001), more Rhythmia® mapping system use (30 vs 8%, p&amp;lt;0.0001), and longer procedure time (129±46 vs 108±39 min, p≤0.0001) than those without SCI, while there were no significant differences in age, LA appendage flow velocity, kind of anti-coagulant agent between the two groups. Multivariate regression analysis identified Rhythmia® use [odds ratio (OR) 4.26, (95% CI 2.32–7.84), p=0.0001], LVEF (OR 1.02, p=0.0059), CHADS2 score (OR 1.27, p=0.009), and procedure time (OR 1.005, p=0.04) as independent risk factors of acute SCI during CA for AF. Conclusion Acute SCI occurred about 16% after CA for AF. Rhythmia® mapping system use exhibited a higher incidence of acute SCI after catheter ablation for AF than the other mapping system use. Rhythmia® mapping system use, LVEF, CHADS2 score, and procedure time are associated with SCI relating CA for AF. Funding Acknowledgement Type of funding source: None