Patients In Normal Sinus Rhythm Research Articles

Atrial imaging and cardiac Rhythm In cryptogenic Embolic Stroke: the ARIES study

Abstract Background One of the underlying causes of cryptogenic stroke is an unknown cardioembolic etiology, and the most frequent is atrial fibrillation (AF). It is not unusual to find non-sustained (<30 s) "microfibrillatory" atrial tachycardias (nsAT) or frequent atrial ectopic beats (AE) during the work-up but its pathological significance remains uncertain. Purpose Our aim is to analyze the risk of developing AF or nsAT in patients with cryptogenic stroke and compare their atrial function using advanced echocardiography and their clinical outcome during the follow-up. Methods The ARIES study (Atrial imaging and cardiac Rhythm In cryptogenic Embolic Stroke) is an observational, prospective study in patients admitted for recent cryptogenic stroke in a comprehensive Stroke Unit. We analyze the frequency of detecting AF and nsAT in two 30-day ECG records with a wearable device and we compare echocardiographic signs of left atrial (LA) dysfunction according to rhythm classification: AF, high-burden nsAT/AE (>2 nsAT/24 hours or >3.000 AE/24 hours respectively) and normal sinus rhythm (NSR). Finally, we evaluate stroke recurrence and mortality at 12-months and report changes in classification of stroke etiology during the follow-up. Results In total prolonged rhythm study (1st and 2nd 1-month wearable EKG), AF was found in 35 (32.1%) patients, high-burden nsAT/AE in 27 patients (24.8%) and normal rhythm was found in 47 patients (43.1%). Patients with AF compared with patients with NSR presented higher values in LA volume (69.9±21.8 vs 49.4±26.5, p<0.001) , LA index volume (38.8±11.2 vs 27.3±11.8 ml/m2, p<0.001), 3D LA index volume (50.6±17.2 vs 34.0±15.4 ml/m2, p<0.001), 3D-telediastolic LA volume (89.5±27.7 vs 66.8 ±31.9 ml/m2, p=0.002), 3D-telesistolic LA volume (43.6±15.3 vs 25.3±17.4 ml/m2, p <0.001), lower rates of LA ejection fraction (50 ±14.6 vs 62.7±11.8, p=0.001) and LA strain in reservoir (22.0±8.6 vs 30.4±10.5, p<0.001) and contraction (10.5±8.18 vs 17.1±7.5, p<0.001). After multivariable regression analysis (age, HTA and CHASDS2VASC) all the differences remained significative. High-burden nsAT/AE and NSR patients presented significant differences in LA index volume (33.4±12.4 vs 27.3±11.8 ml/m2, p=0.043) and LA strain in reservoir (26.6±12.5) vs 31.0±10.1, p=0.034) that disappeared after multivariate regression analysis. There were no significant differences in ischemic recurrence or mortality between the three groups. Conclusions In patients with cryptogenic stroke, we registered a high rate of AF and high-burden nsAT/AE. AF patients showed notable alterations in LA volume, LA function and reservoir and contraction strain, while patients with high-burden nsAT/AE showed less structural alteration in echocardiography without difference in stroke recurrence among groups.

Characteristics and immediate outcomes of patients who underwent percutaneous balloon mitral valvuloplasty at the Jakaya Kikwete Cardiac Institute, Tanzania.

For rheumatic mitral stenosis (MS), a multidisciplinary evaluation is mandatory to determine the optimal treatment: medical, percutaneous balloon mitral valvuloplasty (PBMV) or valve surgery. Clinical and imaging evaluations are essential for procedural risk assessment and outcomes. PBMV interventions are increasingly available in Africa and are feasible options for selected candidates. Enhancing PBMV training/skills transfer across most of African countries is possible. The aim of this study was to provide insight into the clinical practice of patients with rheumatic MS evaluated for PBMV in a Tanzanian teaching hospital and to define the role of imaging, and evaluate the heart team and training/skills transfer in PBMV interventions. From August 2019 to May 2022, 290 patients with rheumatic MS were recruited consecutively in the Tanzania Mitral Stenosis study. In total, 43 (14.8%) patients were initially evaluated for eligibility for PBMV by a heart team. We carried out the clinical assessment, laboratory investigations, transthoracic/oesophageal echocardiography (TTE/TEE) and electrocardiography. The median age was 31 years (range 11-68), and two-thirds of the patients were female (four diagnosed during pregnancy). Two patients had symptomatic MS at six and eight years. Nine patients had atrial fibrillation with left atrial thrombus in three, and two were detected by TEE. Nine patients in normal sinus rhythm had spontaneous echo contrast. The mean Wilkins score was 8.6 (range 8-12). With re-evaluation by the local and visiting team, 17 patients were found to have unfavourable characteristics: Bi-commissural calcification (four), ≥ grade 2/4 mitral regurgitation (six), high scores and left atrial thrombus (three), left atrial thrombus (two), and severe pulmonary hypertension (two). Three patients died before the planned PBMV. Eleven patients were on a waiting list. We performed PBMV in 12 patients, with success in 10 of these, and good short-term outcomes [mean pre-PBMV (16.03 ± 5.52 mmHg) and post-PBMV gradients (3.08 ± 0.44 mmHg, p < 0.001)]. There were no complications. PBMV had good outcomes for selected candidates. TEE is mandatory in pre-PBMV screening and for procedural guidance. In our cohort, patients with Wilkins score of up to 11 underwent successful PBMV. We encourage PBMV skills expansion in low- and middle-income countries, concentrating on expertise centres.

PO-01-214 DEEP LEARNING EVALUATION OF ECHOCARDIOGRAMS TO IDENTIFY OCCULT ATRIAL FIBRILLATION

Atrial fibrillation (AF) can often be missed by routine screening given its frequently paroxysmal and asymptomatic presentation. Deep learning algorithms can identify patients with paroxysmal AF from sinus electrocardiograms. Transthoracic echocardiograms (TTEs) may provide additional structural information complementary to ECGs that could also be used to help identify occult AF. We sought to determine whether deep learning evaluation of echocardiograms of patients in normal sinus rhythm could predict concurrent atrial fibrillation. We identified patients who had TTE performed between 6/2004 and 6/2021. Cases were defined as patients who had a TTE in normal sinus rhythm (NSR) with AF documented on ECG within 90 days before/after the TTE. Controls had a NSR TTE (by report and confirmed by lack of noted mitral A wave velocity) and no documented AF within 90 days by ECG or ICD diagnosis. We trained a video-based convolutional neural network using TTE parasternal long axis (PLAX) videos to predict concurrent AF. Model performance was compared to AF prediction by logistic regression using clinical variables (age, sex, heart failure, hypertension, cerebrovascular disease, peripheral arterial disease, diabetes, height, weight, smoker), CHADS2VASc score, and left atrial (LA) size on TTE. Model was trained on 57,681 TTEs of patients who were on average 66.2 years old (SD 16.9), 44.9% female, with a mean CHADS2VASc score of 3.1 (SD 2.1) and LA area of 19.7cm2 (SD 5.8). When tested on a held-out sample of 7,283 TTEs, the model predicted the occurrence of atrial fibrillation within 90 days of a sinus TTE with an AUC of 0.71 (0.69-0.73). Using the max accuracy threshold, the PPV was 0.20 and the NPV was 0.95. The model performed better than predicting AF using clinical risk factors (AUC 0.67), LA area (AUC 0.63), and CHADS2VASc (AUC 0.61). A deep learning model predicted the occurrence of atrial fibrillation from TTEs moderately well, better than clinical variables or LA size alone. This may open up additional opportunities for screening patients for occult AF.

Catheter ablation of atrial fibrillation in hypertrophic cardiomyopathy: A proportional meta-analysis and systematic review of single-arm studies

Atrial fibrillation (AF) is the most common arrhythmia in patients with hypertrophic cardiomyopathy (HCM). Limited data exists about the efficacy and clinical outcomes of AF ablation in HCM. The purpose of this meta-analysis was to evaluate the role of catheter-based ablation for treatment of AF in patients with HCM. PubMed, SCOPUS, Web of Science, Embase, Cochrane library, and ClinicalTrials.gov were searched for studies discussing outcomes of catheter-based ablation for AF in patients with HCM. Two reviewers independently screened studies and extracted relevant data. Incidence rate estimates from individual studies underwent logit transformation to calculate the weighted summary proportion under the random effect model. A total of 19 reports met the inclusion criteria (1183 patients). The single ablation procedure was successful in 39% patients. Up to 34% patients underwent a repeat ablation. About 41% patients in normal sinus rhythm after successful AF ablation received postprocedure antiarrhythmic drug (AAD) therapy. Patients undergoing successful AF ablation experienced a significant improvement in the New York Heart Association functional class (standardized mean difference -1.03; 95% confidence interval -1.23 to -0.83; P < .00001). AF ablation appears to be safe and feasible in patients with HCM. Freedom from AF after undergoing successful ablation is associated with significant improvement in heart failure symptoms.

Abstract 15059: Effects of Cigarette Smoke on Inflammation and Atrial Fibrillation

Introduction: Cigarette smoking is a major risk factor for occurrence and progression of several cardiovascular diseases. Smoking is associated with an increased risk of Atrial Fibrillation (AF). AF is an extremely common cardiac rhythm disorder that is associated with substantial morbidity and mortality. One of the main contributors for the initiation, progression and persistence of AF is inflammation. Cigarette smoke (CS) is known to increase inflammation. CS is known to increase pro-inflammatory cytokines and AF progression is associated with increased levels of these pro-inflammatory cytokines. Therefore, it is of great clinical importance to elucidate the underlying mechanisms contributing to smoking induced inflammation. The amplification of the pro-inflammatory cytokines is mediated by inflammasome and recently, the direct involvement of the NLRP3 (NACHT, leucine-rich repeat, and pyrin domain containing protein 3), inflammasome and AF has been demonstrated in patients with AF. The central hypothesis to be tested is that patients with AF and exposed to CS will demonstrate a heightened inflammation through the activation of NLRP3 inflammasome compared to patients in normal sinus rhythm (NSR) and non-smoking AF patients. Methods: Human atrial tissues and blood were obtained from patients undergoing coronary artery bypass graft surgery at UC Davis Medical Center in accordance with the approved UC Davis IRB protocol. An integrated approach using molecular biology, flow cytometry, and electrophysiology was used to test the components of NLRP3 inflammasome, inflammatory cytokines and structural remodeling in smoking and non-smoking AF and NSR patients using blood and human atrial tissue. Results: Our results demonstrate a significant increase in protein expression of component of the NLRP3 inflammasome including NLRP3, ASC and Caspase-1 in smoking AF and NSR patients compared to non-smoking patients. There was a significant increase in inflammatory cytokines activated by the NLRP3 inflammasome, IL-18 and IL-1β in in smoking AF and NSR patients compared to non-smoking patients. Conclusions: Our study not only provides important mechanistic insights into the roles of inflammasome in AF patients exposed to CS

Hybrid ablation of persistent and long-standing persistent atrial fibrillation with depressed ejection fraction: A single-center observational study

ObjectiveThe relationship between atrial fibrillation (AF) and heart failure with depressed ejection fraction (EF) is complex. AF-related tachycardia-mediated cardiomyopathy (TMC) can lead to worsening EF and clinical heart failure. We sought to determine whether a hybrid team ablation approach (HA) can be performed safely and restore normal sinus rhythm in patients with TMC and heart failure and to delineate the effect on heart failure. MethodsWe retrospectively analyzed patients with nonparoxysmal (ie, persistent and long-standing persistent) AF-related TMC with depressed left ventricular EF (LVEF ≤40%) and heart failure (New York Heart Association [NYHA] class ≥2) who underwent HA between 2013 and 2018 and had at least 1 year of follow-up. Pre-HA and post-HA echocardiograms were compared for LVEF and left atrial (LA) size. Rhythm success was defined as <30 seconds in AF/atrial flutter/atrial tachycardia without class I or III antiarrhythmic drugs. Results are expressed as mean ± SD and 95% confidence interval (CI) of the mean. ResultsForty patients met the criteria for inclusion in our analysis. The mean patient age was 67 ± 9.4 years. The majority of patients had long-standing persistent AF (26 of 40; 65%), and the remainder had persistent AF (14 of 40; 35%). All patients had NYHA class II or worse heart failure (NYHA class II, 36 of 40 [90%]; NYHA class III, 4 of 40 [10%]). The mean time in AF pre-HA was 5.6 ± 6.7 years. All patients received both HA stages. No deaths or strokes occurred within 30 days. Three new permanent pacemakers (7.5%) were placed. Rhythm success was achieved in >60% of patients during a mean 3.5 ± 1.9 years of follow-up. LVEF improved significantly by 12.0% ± 12.5% (95% CI, 7.85%-16.0%; P < .0001), and mean LA size decreased significantly by 0.40 cm ± 0.85 cm (95% CI, 0.69-0.12 cm; P < .01), with a mean of 3.0 ± 1.5 years between pre-HA and post-HA echocardiography. NYHA class improved significantly after HA (mean pre-HA NYHA class, 2.1 ± 0.3 [95% CI, 2.0-2.2]; mean post-HA NYHA class, 1.5 ± 0.6 [95% CI, 1.3-1.7]; P < .0001). ConclusionsThoracoscopic HA of AF in selected patients with TMC heart failure is safe and can result in rhythm success with structural heart changes, including improvements in LVEF and LA size.

Update on Antiarrhythmic Therapy: Dofetilide

Dofetilide is one of the several novel methanesulfonamide compounds that selectively inhibits the rapid component of the delayed rectifier potassium current, IKr, thus prolonging the effective refractory period (ERP) and the action potential duration (APD) in both the atria and the ventricles. It has no effects on sodium and calcium channels, and therefore, has minimal effects on myocardial conduction velocity. Dofetilide can be administered either orally or intravenously, and has a rapid onset of action. It was recently approved in the United States for the maintenance and conversion of normal sinus rhythm in patients with atrial fibrillation (AF).

Low left atrial appendage emptying velocity is a predictor of atrial fibrillation recurrence after catheter ablation.

Recurrence of atrial fibrillation (AF) after catheter ablation (CA) remains common and studies have shown about 5%-9% annual recurrence rate after CA. We sought to assess the echocardiogram derived left atrial appendage (LAA) emptying velocity as a predictor of AF recurrence after CA. To determine if LAA emptying is a marker of recurrence of AF post-CA METHODS: A total of 303 consecutive patients who underwent CA for AF between 2014 and 2020 were included. Baseline clinical characteristics and echocardiographic data of the patients were obtained by chart review. LAA emptying velocities were obtained from transesophageal echocardiogram (TEE). LA voltage was obtained during the mapping for CA. Chi-square test and nominal logistic regression were used for statistical analysis. An receiver operator characteristic curve was used to determine LAA velocity cut-off. Mean patient age was 61.7 ± 10.5; 32% were female. Mean LAA emptying velocity was 47.5 ± 20.2. A total of 103 (40%) patients had recurrence after CA. In the multivariable model, after adjusting for potential confounders, LAA emptying velocity of ≥52.3 was associated with decreased AF recurrence postablation (odds ratio [OR]: 0.55; 95% confidence interval [CI]: 0.31-0.97; p = .03*). There were 190 (73%) patients in normal sinus rhythm during TEE and CA, and sensitivity analysis of these patients showed that LAA velocity ≥52.3 remained associated with decreased AF recurrence (OR: 0.35; 95% CI: 0.15-0.82; p = .01*). LAA emptying velocity measured during preprocedural TEE can serve as a predictor of AF recurrence in patients undergoing CA.

Holter monitoring for assessment of possible paroxysmal atrial fibrillation as a cause in otherwise normal sinus rhythm patients with acute ischemic stroke: a hospital based study

Background: Stroke/ cerebrovascular accidents are common and among the major causes of mortality and morbidity. Thromboembolism are also among the causes of ischemic strokes. Diagnosis of atrial fibrillation makes the difference in the management of ischemic strokes for long term as anticoagulation are given in these cases for prevention of further embolic events.&#x0D; Methods: A prospective observational study was done from july 2019 to june 2021 for patients admitted for ischemic strokes who were otherwise found to have normal sinus rhythm. A 24 hour holter monitor was connected and analyzed for possible paroxysmal atrial fibrillation. Baseline investigations including trans-thoracic echocardiography was done. Data were analyzed and results were sought.&#x0D; Results: Out of 212 patients admitted for stroke, only 116 were eligible for the study. Male female ratio was 2:1. Ninety-four percent of patients had at least one or more risk factors: Smokers (74%) followed by Hypertensives (70%), Dyslipidemics (54%) and Diabetics (20%). Twenty-two percent of patients were found to have paroxysmal atrial fibrillation. There was no gender difference between the occurrences of paroxysmal atrial fibrillation. Among the risk factors, smoking and hypertension were significantly associated with the occurrence of paroxysmal atrial fibrillation (P: 0.001 and 0.002 respectively) while other risk factors like diabetes and dyslipidemia had no significant association. There was significant association of paroxysmal atrial fibrillation with mortality (P: 0.0013).&#x0D; Conclusion: Patients who are in otherwise normal sinus rhythm in electrocardiography with ischemic cerebrovascular accidents may have paroxysmal atrial fibrillation as cause of event. Smoking and hypertensive patients are significantly associated with occurrence of paroxysmal atrial fibrillation and stroke and these patients are more likely to die than the patients having normal heart rhythm. Management of these patients definitely defer in terms of possible use of anticoagulants.

Abstract 10920: Cost-Effectiveness of Pulmonary Vein Isolation with Epicardial Left Atrial Appendage Ligation for the Treatment of Non-Paroxysmal Atrial Fibrillation

Introduction: Electrical isolation of the left atrial appendage (LAA) using percutaneous epicardial ligation may improve catheter ablation outcomes for non-paroxysmal atrial fibrillation (AF) patients. Little is known regarding the cost effectiveness of this procedure. Hypothesis: We hypothesized that cost-effectiveness between pulmonary vein isolation (PVI) + LAA epicardial ligation using a percutaneous LARIAT ® Suture Delivery Device would be cost effective (CE) compared to PVI alone over 5 years. Methods: A Markov model simulated outcomes for a population with annual stroke risk of 4.6% (CHA 2 DS 2 -VASc score 3). Model inputs for procedure efficacy, stroke and bleed events, health utility, and event costs were estimated from literature. Procedure costs from Medicare rates were used. The model had a 5-year time-horizon and US payer perspective. Univariate and probabilistic sensitivity analyses (PSA) were performed. Outcomes were health care costs and quality-adjusted life-years (QALYs). In the base case, PVI + LAA ligation efficacy from published studies was 67% after 1-year, with an estimated 25% oral anticoagulant (OAC) utilization in PVI + LAA ligation patients in normal sinus rhythm 13-60 months after the index procedure. Cost effectiveness thresholds were evaluated with alternative PVI + LAA ligation efficacy and OAC utilization rates, including 1-year PVI + LAA ligation efficacies of 67%, 70%, 75%, and 80% and OAC utilization of 20-60%. Results: In the base case, PVI + LAA ligation had a mean 5-year cost of $72,865 with 3.25 QALYs and PVI alone had mean cost of $69,936 with 3.19 QALYs. The incremental cost-effectiveness ratio was $46,716; PVI + LAA ligation was CE at $50,000 per QALY gained. In PSA, 64% and 82% of simulations were CE at $50,000 and $100,000 per QALY gained, respectively. In various scenarios, procedure efficacy of 75% combined with OAC utilization of 50% or below yielded CE at $50,000 per QALY gained. Reduction of OAC utilization to 30% yielded CE at $50,000 per QALY gained, regardless of efficacy. Conclusions: In the base case, PVI + LAA ligation was CE at $50,000 per QALY gained when compared to PVI alone. The CE threshold for efficacy was 75% and OAC utilization was 30%. Cost savings were driven by reductions in OAC use and increased efficacy.

Abstract 12251: Speckle Tracking Echocardiography Changes in Patients Who Developed Atrial Fibrillation Post Coronary Artery Bypass Grafting

Introduction: Postoperative atrial fibrillation (POAF) is seen in around 30% of patients after coronary artery bypass grafting (CABG). It is associated with increased risk for stroke, heart failure, in-hospital mortality and hospital readmission. Prediction of POAF could help institute preventive and early treatment strategies. Methods: We queried PubMed, Ovid Medline, and Cochrane databases for key words ‘atrial speckle tracking” and/or “reservoir strain” and/or “post-operative atrial fibrillation”. We included studies that included patients in normal sinus rhythm before CABG and compared reservoir strain and/or peak atrial longitudinal strain (PALS) between patients who developed POAF and those who did not. Continuous data (LA strain) was pooled as a mean difference comparing patients who developed POAF versus patients who did not. We used the inverse variance method with the Restricted Maximum likelihood estimator of Tau2, for random effect analysis. We used Q and I2 statistics to calculate the heterogeneity. Results: Six observational studies met our inclusion criteria with a total of 338 patients, of which 91 patients developed POAF. Left atrial reservoir strain was significantly reduced in patients who developed POAF as compared with those who did not develop POAF, mean difference(MD), 95% confidence interval(CI): -13.97(-15.00-12.93), I2= 53%, , P &lt;0.00001, Figure 1. Conclusions: Atrial reservoir strain was significantly reduced in patients who developed POAF as compared to those who remained in sinus rhythm. Atrial reservoir strain can be potentially used to identify patients at risk of POAF. More data is needed for further validation of this finding. .

Abstract 13526: Left Atrial Appendage Emptying Velocity is a Predictor of Atrial Fibrillation Recurrence in Patients Undergoing Catheter Ablation

Introduction: Low left atrial (LA) voltage is known to predict Atrial Fibrillation (AF) recurrence after catheter ablation (CA); however, its measurement involves invasive electrophysiology study (EPS). Left Atrial Appendage (LAA) emptying velocities are routinely measured during pre-procedural Transesophageal Echocardiography (TEE). We sought to assess the association between LAA velocities and AF recurrence after CA. Hypothesis: Pre-procedural LAA emptying velocity is a predictor of AF recurrence in patients undergoing CA. Methods: A total of 263 consecutive patients who underwent CA for AF between 2014 and 2020 were included. Baseline clinical characteristics and echocardiographic data of the patients were obtained by chart review. LAA emptying velocities were obtained from TEE. LA voltage was obtained during the EPS. Chi-square test and nominal logistic regression were used for statistical analysis. A sensitivity of 80% on the ROC curve was used for determining LAA velocity cut-off. Results: Mean patient age was 60.8±10.9; 34% were female. Mean LAA emptying velocity was 48.0±20.4. Mean average total voltage (Vavg) of LA was 1.58±1.05. There was a significant positive linear correlation between LAA velocity and LA Vavg (p=0.004*). A total of 68 (26%) patients had recurrence after CA. Patients with lower LA Vavg had increased AF recurrence compared to patients with higher LA Vavg (p=0.004*). In the multivariable model, after adjusting for HTN, CAD, HFrEF, and DM, LAA emptying velocity of ≥52.3 was associated with decreased AF recurrence post-ablation (OR 0.31; 95% CI 0.15-0.66; p = 0.002*). There were 190 (73%) patients in normal sinus rhythm during EPS mapping, and sensitivity analysis of these patients showed that LAA velocity ≥52.3 remained associated with decreased AF recurrence (OR 0.35; 95% CI 0.15-0.82; p = 0.01*). Conclusions: LAA emptying velocity measured during pre-procedural TEE can serve as a predictor of AF recurrence in patients undergoing CA.

Abstract P476: Determinants Of Atrial Fibrillation Mechanisms Using Metabolomic Profiling

Introduction: Atrial fibrillation (AF) represents one of the most common arrhythmias seen clinically, yet, current treatment paradigms have proven largely inadequate. One of the main contributors to the pathophysiology of AF is inflammation. Hence, reduction of inflammation associated atrial remodeling represents a novel therapeutic strategy for the treatment of AF. Oxylipins are derived from arachidonic acid, which is metabolized through three pathways including the cytochrome P450 (CYP450) pathway. The CYP450 products, epoxyeicosatrienoic acids (EETs), are major anti-inflammatory metabolites with several cardioprotective effects. The central hypothesis to be tested is that patients with AF will demonstrate an increase in oxylipin profiles towards inflammatory features compared to patients with normal sinus rhythm (NSR). We further hypothesize that lipid mediators may represent a new therapeutic target for AF. Methods: In the cross sectional study, human atrial appendage specimens and blood from informed and consented patients undergoing coronary artery bypass graft surgery were obtained in accordance with the approved UC Davis IRB protocol. Metabolomic profiling and inflammatory cytokines were assessed from the plasma of patients using LC-MS/MS. The underlying mechanisms of AF were determined using an integrated approach with molecular biology, flow cytometry, and electrophysiology. Results: Metabolomic profiling shows a significant decrease in the EETs/DHETs ratios and EpOMEs/DiHOMEs ratios in the cohort with AF compared to patients in NSR. There was a significant increase in inflammatory cytokine, chemokine levels and oxidative stress in patients with AF compared to patients in NSR. There was a significant increase in nuclear translocation of NF-κB (nNF-κB) from patients with AF compared to NSR using western blot analysis. Assessment of total IκB and phosphorylated-IκB (pIκB) levels showed a decrease in IκB level and an increase in the pIκB levels associated with the activation of NF-κB in AF compared to the NSR cohort. Conclusions: The study provides important insights into metabolomic profiles in patients with AF and reveals the prospect of oxylipins being a novel therapeutic target in the treatment of AF.

Ventricular repolarization homogeneity in transthyretin cardiac amyloidosis

Abstract Funding Acknowledgements Type of funding sources: None. Background Non-sustained ventricular tachycardia is frequently observed in patients with transthyretin cardiac amyloidosis (TTR-CA); however, the incidence of sudden tachyarrhythmic death is low. Homogeneity of amyloid fibril deposition within the myocardium and conduction system may mitigate against sustained ventricular tachyarrhythmias. In contrast, myocardial scar heterogeneity is an established predictor of sudden cardiac death in conditions such as hypertrophic cardiomyopathy (HCM), as evidenced by increased myocardial dispersion of repolarization. Whether such indices of arrhythmogenesis are evident in TTR-CA has not been established. Purpose To compare ventricular repolarization indices in TTR-CA to HCM and controls without known cardiovascular disease. Methods We identified TTR-CA and HCM patients from our single center respective registries, and control patients from our clinical ECG database. Only patients in normal sinus rhythm without bundle branch block, cardiac pacing or artifact were included for analysis. Demographic and clinical data were abstracted. ECGs were analyzed at 25 mm/s paper speed and 10 mm/mV amplitude. ECG parameters included QT interval, QT dispersion, and T peak to T end (TpTe) using the tangent method. All measurements were performed by two blinded independent cardiologists. Results A total of 112 patients (45 TTR-CA, 32 HCM, and 35 controls) were studied. Despite a longer QTc in TTR-CA (468.4 ms in TTR-CA vs. 424.6 in controls; p &amp;lt; 0.001), patients with TTR-CA demonstrated similar repolarization indices as controls, including TpTE (93.0 ± 13.5 ms in TTR-CA vs 86.4 ± 12.2 ms in controls, p = 0.24), and TpTe/QTc (0.20 ± 0.03 in TTR-CA vs 0.2 ± 0.03 in controls, p = 0.99). In contrast, HCM patients demonstrated greater TpTe and TpTe/QTc compared with controls (Figure). and a trend toward increased QT dispersion in HCM vs. TTR-CA (p = 0.06). Conclusion Unlike HCM, patients with TTR-CA demonstrate a relative lack of myocardial repolarization heterogeneity compared with controls. This finding correlates with homogeneous distribution of myocardial amyloid fibrils and may explain the low observed incidence of sudden cardiac death in this population. Abstract Figure

Epicardial fat and the risk of atrial tachy-arrhythmia recurrence post pulmonary vein isolation: a computed tomography study.

Epicardial and Pericardia fat have been hypothesized to exert local and systemic pathogenic effects on nearby cardiac structures. The present study aimed to evaluate the impact of epicardial and pericardial fat volumes on the outcome of patients that underwent a first pulmonary vein isolation (PVI) with cryoablation. We included 130 consecutive patients with atrial fibrillation (AF) that underwent contrast enhanced ECG-gated cardiac computed tomography (CCT) before a PVI. The control group included 50 patients in normal sinus rhythm that underwent ECG-gated CT to rule out coronary artery disease. Epicardial and pericardial fat volumes were quantified with CCT. Patients with AF compared to patients with normal sinus rhythm (control group) had significantly larger epicardial (140.3 ± 58.1 vs. 55.9 ± 17.7ml; respectively, P < 0.001) and pericardial (77.0 ± 35.5ml vs. 27.2 ± 9.5ml; respectively, P < 0.001) fat volumes. Among patients that underwent PVIs, those with AF recurrence had a greater epicardial (175.0 ± 54.4ml vs. 130.7 ± SD 54.2ml; respectively, P < 0.001) and pericardial (93.7 ± SD 42.8 vs. 72.5 ± SD 31.9ml; respectively, P < 0.001) fat volumes, compared to patients with no AF recurrence. Multivariate analyses revealed that epicardial fat was an independent predictor of recurrence post-ablation (HR = 1.08, 95% CI 1.02-1.16 per 10-ml increase in volume; P = 0.009). Pericardial fat was associated with 7% increase in risk of recurrent AF (HR = 1.07, 95% CI 0.98-1.18; P = 0.117). Epicardial fat, assessed with contrast enhanced CCT, is an independent predictor of AF recurrence after PVI ablation.

Accuracy of a single-lead mobile smartphone electrocardiogram for QT interval measurement in patients undergoing maintenance methadone therapy.

Methadone is associated with QT interval prolongation and torsades de pointes. Expert panel recommendations advocate a pre-methadone electrocardiogram (ECG) and another ECG at 30 days of therapy in patients with risk factors. Some guidelines recommend a pre-methadone ECG and routine ECG monitoring in all methadone patients, but this is controversial due to the resources required. Availability of a convenient, less resource-intensive method of ECG monitoring for patients taking methadone is desirable. The objective of this study was to assess the accuracy of a handheld smartphone ECG (iECG) for QT measurement in patients on maintenance methadone therapy in an urban opioid treatment program. Prospective study. Urban opioid treatment program. n = 115 patients in normal sinus rhythm who were on steady-state maintenance methadone therapy INTERVENTION: Patients (n = 115) underwent a simultaneous 12-lead ECG and a single-lead iECG. The first three QT and RR intervals from lead II of the 12-lead ECG and simulated lead I from the iECG were compared using the Bland-Altman analysis of measurement agreement. Mean [± standard deviation) age was 34 ± 11 years; 71% were female, 75% were white. Compared to the 12-lead ECG, the iECG was associated with a QTc bias of - 0.14 ms (SD = 12 ms, 95% CI = -2.4 to 2.1 ms). The absolute mean difference in QTc between the two methods was 9.5 ± 7.1 ms. For identification of patients with methadone-associated QTc prolongation, the iECG performed moderately well [c-statistic 0.97 (95% CI 0.91-0.99); sensitivity and specificity 75% (95% CI 43-95%) and 99% (95% CI 94-99%), respectively]. The positive and negative likelihood ratios of the iECG for identifying patients with methadone-associated QTc prolongation were 77.25 (95% CI 10.69 to 558.18) and 0.25 (95% CI 0.09 to 0.67), respectively, while the positive and negative predictive values were 90% (95% CI 56-99%) and 97% (95% CI 92-99%), respectively. The accuracy of the iECG for identifying patients with QTc prolongation was 97% (95% CI 91-99%). A handheld smartphone ECG is accurate for QT interval measurement in patients taking maintenance methadone therapy, and its performance is moderately good for identifying patients with methadone-associated QTc prolongation.

Abstract 14368: Artificial Intelligence-Electrocardiography to Predict Time to Atrial Fibrillation: An Analysis of Mayo Clinic Study of Aging

Introduction: An artificial intelligence (AI) algorithm applied to electrocardiography (ECG) during normal sinus rhythm (NSR) has been shown to predict concomitant atrial fibrillation (AF). We sought to characterize the value of AI-ECG as a predictor of future AF and assess its performance compared to other clinical prediction scores in a population-based sample. Methods: We calculated the AI-ECG probability during NSR in patients who enrolled in the population-based Mayo Clinic Study of Aging with at least one ECG in NSR within two years prior and no history of AF at the time of the baseline study visit. The cumulative incidence of AF was estimated for strata defined by AI-ECG probability and CHARGE-AF score. Cox proportional hazards were fit to assess the independent prognostic value and interaction of AI-ECG probability and CHARGE-AF score. Concordance (c) statistics were calculated for AI-ECG probability, CHARGE-AF score and combined AI-ECG and CHARGE-AF score. Results: A total of 1,936 patients with a median age 75.8 (quartile range [QR] 70.4, 81.8) years, median CHARGE-AF score 14.0 (QR 13.2, 14.7) and median CHADS2VASC score 3 (QR 2, 4) were included in the analysis. The cumulative incidence of AF increased in a stepwise fashion across quartiles of AI-ECG probability and CHARGE-AF score (Figure 1). When compared in the same model, both AI-ECG probability (hazard ratio [HR] 1.76, 95% confidence interval [CI] 1.51-2.04) and CHARGE-AF score (HR 1.90, 95% CI 1.58-2.28) independently predicted AF without significant interaction (p=0.54). C statistics were 0.69 (95% CI 0.66-0.72) for AI-ECG probability, 0.69 (95% CI 0.66-0.71) for CHARGE-AF and 0.72 (95% CI 0.69-0.75) for combined AI-ECG and CHARGE-AF score. Conclusions: In the Mayo Clinic Study of Aging, both the AI-ECG probability and CHARGE-AF score independently predicted time to AF. The AI-ECG may offer a means to assess risk with a single test without requiring manual or automated clinical data abstraction.

Restoration of normal sinus rhythm in atrial fibrillation: impact of reverse remodelling of right chambers on tricuspid regurgitation severity

Abstract Background The severity of tricuspid regurgitation (TR) in patients with restored normal sinus rhythm (SR) after atrial fibrillation (AF) has been poorly assessed. Purpose Our study aimed to assess (1) right chamber remodelling and (2) TR severity in patients with AF who have had their rhythms restored to normal sinus. Methods We prospectively evaluated 94 consecutive patients hospitalized for AF who received either ablation, direct current cardioversion, or pharmacological therapy. Patients were divided into two groups according to their cardiac rhythm at 6 months follow up (6M): restoration to SR (SR group, n=54), persistence of AF (AF group, n=40). TR vena contracta (VC), TR grade severity was divided into 4 grades using an integrated approach (0: none or trace; 1: mild; 2: moderate; 3: severe TR). Two dimensional (2D) end diastolic (ED) tricuspid annulus (TA) diameter in the apical 4 chambers view, three-dimensional (3D) indexed volumes (3D Vi) of the right atrium (RA) and right ventricle (RV) in end systole (ES) and ED were acquired using transthoracic echocardiography at admission and at 6M. Results At 6M, in the SR group a significant improvement in TR VC (Figure A) and TR grade (Figure B) were noted, whereas there was no differences in the AF group (0.41 vs. 0.42cm, p=0.24 for TR VC; 1.70 vs. 1.76, p=0.16 for mean TR grade). In the SR group a significant reduction in 3D ES RV Vi, 2D ED TA diameter, 3D ES and ED Vi of the RA (Table) were observed. Regression of TR VC was correlated with regression of right cavities parameters (ρ=0.47, p&amp;lt;0.001 for 2D ED TA diameter; ρ=0.34, p&amp;lt;0.005 for 3D ES RA Vi; ρ=0.33, p&amp;lt;0.005 for 3D ED RV Vi; ρ=0.29, p&amp;lt;0.005 for 3D ES RV Vi). Conclusion Restoration of normal SR in patients with AF results in beneficial remodelling of right cavities at 6M of follow-up which were associated with a significant decrease in TR severity. Strategies for normal SR restoration in patients with AF and TR should be vigorously attempted. TR Evolution Funding Acknowledgement Type of funding source: None

Can left atrial mechanics predict anticoagulation in cryptogenic stroke?

Abstract Introduction Ischemic stroke is a leading cause of death and disability in the Western world, frequently due to cardioembolism and atherothromboembolism. Cryptogenic strokes occur without a well-defined aetiology after a standard vascular and cardiac evaluation, and secondary prevention may include antiplatelet therapy while awaiting results of long-term cardiac monitoring. In this study, we aimed to identify echocardiographic predictors of paroxysmal atrial fibrillation (AF) latter identified in follow-up of patients with cryptogenic stroke. Methods We retrospectively assessed all patients with cryptogenic stroke admitted in our hospital in the last 2 years. Only patients in normal sinus rhythm with a minimum of 24 hours of cardiac monitoring at admission and 24 hours Holter monitor within 6 months after discharge were included. Echocardiographic measures included left ventricle ejection fraction, left atrium (LA) volume, left and right atrium longitudinal strain, left and right ventricle longitudinal strain, E/A ratio, E/e' ratio, isovolumetric relaxation time (IVRT) and E wave deacceleration time. Echocardiographic data was assessed to determine its accuracy to identify AF. Results The study included 32 patients with a mean age of 72±10 years and a male preponderance (87.5%). AF was identified in 12 (37.5%) patients. This group of patients had a larger indexed LA volume (44.3 vs 29.1 mL/m2, p=0.043), a lower IVRT (87 vs 116 ms, p=0.028), and a lower LA longitudinal strain in contractile (6.7 vs 13.6%, p&amp;lt;0.001) and in reservoir phase (17.1 vs 23.6%, p=0.042). All other variables were not significantly different among groups, including LA longitudinal strain in conduit phase. LA longitudinal strain in contractile phase showed the best predictive power with an area under the ROC curve of 0.925 (95% CI 0.82–1 p=0.001). The cut-off value that best predicted AF was 8.17% with a sensitivity of 1 and specificity of 0.9. Conclusion LA longitudinal strain in contractile phase is a powerful method to identify AF in cryptogenic stroke. When reduced, anticoagulation may be considered in order to prevent recurrence. Further studies are warranted to reproduce these results in larger cohorts. Funding Acknowledgement Type of funding source: None

Detección de señales cardíacas arrítmicas a partir de registros de ECG utilizando el plano Entropía-Complejidad

El objetivo de este trabajo fue analizar en el plano Entropía-Complejidad (HxC) un conjunto de series de tiempo provenientes de ECG de seres humanos con el objetivo de discriminar registros de dos grupos diferentes de pacientes: los de ritmo sinusal normal, y los de arritmias cardíacas.Las series de tiempo utilizadas en este artículo se obtuvieron de la base de registros de ECG de PhysioNet. El set estuco compuesto por 47 señales de pacientes con arritmias cardíacas diagnosticadas y 18 señales de pacientes con ritmo sinusal normal.El plano HxC se construyó con la entropía de Shannon como eje X, y con la complejidad estadística como eje Y. Dado que el contenido de información de las series de tiempo se transmite en forma de una función de distribución de probabilidad, FDP, ésta se obtuvo por medio de la metodología propuesta por Bandt &amp; Pompe (2002).Los valores medios de complejidad estadística y entropía de Shannon normalizada se calcularon y analizaron en el plano HxC para cada serie de tiempo, donde los valores medios de complejidad de las series de tiempo de ECG de pacientes con arritmias diagnosticadas fueron mayores que el grupo de ritmo sinusal normal. Por otro lado, los valores medios de la entropía de Shannon para los pacientes con arritmias fueron más bajos que los del grupo de ritmo sinusal normal. Estas notorias características hicieron posible la discriminación de los diferentes espacios para ambos grupos de señales en el plano HxC. Los resultados se analizaron mediante una hipótesis de prueba estadística multivariada.La metodología propuesta tiene una notable simplicidad conceptual, velocidad computacional, y robustez al ruido, mostrando además una promisoria eficacia en la detección de patologías cardiovasculares.