Substrate Imaging Before Catheter Ablation of Ventricular Tachycardia: Risk Prediction for Acute Hemodynamic Decompensation.

BACKGROUND: The PAINESD (Pulmonary disease, Age, Ischemic cardiomyopathy, NYHA functional class, Ejection fraction, Storm, Diabetes mellitus) risk score has been validated as a predictor of periprocedural acute hemodynamic decompensation (AHD) in patients undergoing ventricular tachycardia (VT) ablation. Whether the addition of total scar volume (TSV) determined by preprocedure computed tomography imaging provides additional risk stratification has not been previously investigated. OBJECTIVES: The purpose of this study was to evaluate the impact of TSV on the risk of AHD and its adjunctive benefit to the PAINESD score newly modified as Pulmonary disease, Age, Ischemic cardiomyopathy, NYHA class, Ejection fraction, Storm, Scar volume, Diabetes mellitus (PAINES2D) based on the addition of scar volumes. METHODS: This was a retrospective analysis of all index VT ablations at a quaternary care center from 2017 to 2022. Associations between TSV and AHD were evaluated among patients with structural heart disease. RESULTS: Among 61 patients with TSV data, 13 (21%) had periprocedural AHD. TSV and PAINESD were independently associated with AHD risk. Both TSV and PAINESD were associated with AHD (P = 0.016 vs P = 0.053, respectively). The highest TSV tertile (≥37.30 mL) showed significant association with AHD (P = 0.018; OR: 4.80) compared to the other tertiles. The PAINESD and PAINES2D scores had significant impact on AHD (P = 0.046 and P = 0.010, respectively). The PAINES2D score had a greater impact on AHD compared to PAINESD (area under the curve: 0.73; P = 0.011; 95% CI: 0.56-0.91 and area under the curve: 0.67; P = 0.058; 95% CI: 0.49-0.85, respectively). CONCLUSIONS: Addition of TSV to a modified PAINESD score, PAINES2D, enhances risk prediction of AHD. Further prospective study is needed to assess benefit in various cardiomyopathy populations undergoing VT ablation.

Forward-Solution Noninvasive Computational Arrhythmia Mapping: The VMAP Study.

BACKGROUND: The accuracy of noninvasive arrhythmia source localization using a forward-solution computational mapping system has not yet been evaluated in blinded, multicenter analysis. This study tested the hypothesis that a computational mapping system incorporating a comprehensive arrhythmia simulation library would provide accurate localization of the site-of-origin for atrial and ventricular arrhythmias and pacing using 12-lead ECG data when compared with the gold standard of invasive electrophysiology study and ablation. METHODS: The VMAP study (Vectorcardiographic Mapping of Arrhythmogenic Probability) was a blinded, multicenter evaluation with final data analysis performed by an independent core laboratory. Eligible episodes included atrial and ventricular: tachycardia, fibrillation, pacing, premature atrial and ventricular complexes, and orthodromic atrioventricular reentrant tachycardia. Mapping system results were compared with the gold standard site of successful ablation or pacing during electrophysiology study and ablation. Mapping time was assessed from time-stamped logs. Prespecified performance goals were used for statistical comparisons. RESULTS: A total of 255 episodes from 225 patients were enrolled from 4 centers. Regional accuracy for ventricular tachycardia and premature ventricular complexes in patients without significant structural heart disease (n=75, primary end point) was 98.7% (95% CI, 96.0%-100%; P<0.001 to reject predefined H0 <0.80). Regional accuracy for all episodes (secondary end point 1) was 96.9% (95% CI, 94.7%-99.0%; P<0.001 to reject predefined H0 <0.75). Accuracy for the exact or neighboring segment for all episodes (secondary end point 2) was 97.3% (95% CI, 95.2%-99.3%; P<0.001 to reject predefined H0 <0.70). Median spatial accuracy was 15 mm (n=255, interquartile range, 7-25 mm). The mapping process was completed in a median of 0.8 minutes (interquartile range, 0.4-1.4 minutes). CONCLUSIONS: Computational ECG mapping using a forward-solution approach exceeded prespecified accuracy goals for arrhythmia and pacing localization. Spatial accuracy analysis demonstrated clinically actionable results. This rapid, noninvasive mapping technology may facilitate catheter-based and noninvasive targeted arrhythmia therapies. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT04559061.

Role of Electrical Delay in Cardiac Resynchronization Therapy Response.

Traditionally, left ventricular (LV) lead position was guided by anatomic criteria of pacing from the lateral wall of the LV. However, large trials showed little effect of LV lead position on outcomes, other than noting worse outcomes with apical positions. Given the poor correlation of cardiac resynchronization therapy (CRT) outcomes with anatomically guided LV lead placement, focus shifted toward more physiologic predictors such as targeting the areas of delayed mechanical and electrical activation. Measures of left ventricular delay and interventricular delay are strong predictors of CRT response.

Diagnostic accuracy and performance of artificial intelligence in measuring left atrial volumes and function on multiphasic CT in patients with atrial fibrillation.

OBJECTIVES: To evaluate the effectiveness of a novel artificial intelligence (AI) algorithm for fully automated measurement of left atrial (LA) volumes and function using cardiac CT in patients with atrial fibrillation. METHODS: We included 79 patients (mean age 63 ± 12 years; 35 with atrial fibrillation (AF) and 44 controls) between 2017 and 2020 in this retrospective study. Images were analyzed by a trained AI algorithm and an expert radiologist. Left atrial volumes were obtained at cardiac end-systole, end-diastole, and pre-atrial contraction, which were then used to obtain LA function indices. Intraclass correlation coefficient (ICC) analysis of the LA volumes and function parameters was performed and receiver operating characteristic (ROC) curve analysis was used to compare the ability to detect AF patients. RESULTS: The AI was significantly faster than manual measurement of LA volumes (4 s vs 10.8 min, respectively). Agreement between the manual and automated methods was good to excellent overall, and there was stronger agreement in AF patients (all ICCs ≥ 0.877; p < 0.001) than controls (all ICCs ≥ 0.799; p < 0.001). The AI comparably estimated LA volumes in AF patients (all within 1.3 mL of the manual measurement), but overestimated volumes by clinically negligible amounts in controls (all by ≤ 4.2 mL). The AI's ability to distinguish AF patients from controls using the LA volume index was similar to the expert's (AUC 0.81 vs 0.82, respectively; p = 0.62). CONCLUSION: The novel AI algorithm efficiently performed fully automated multiphasic CT-based quantification of left atrial volume and function with similar accuracy as compared to manual quantification. Novel CT-based AI algorithm efficiently quantifies left atrial volumes and function with similar accuracy as manual quantification in controls and atrial fibrillation patients. KEY POINTS: • There was good-to-excellent agreement between manual and automated methods for left atrial volume quantification. • The AI comparably estimated LA volumes in AF patients, but overestimated volumes by clinically negligible amounts in controls. • The AI's ability to distinguish AF patients from controls was similar to the manual methods.

Deep learning model to quantify left atrium volume on routine non-contrast chest CT and predict adverse outcomes.

BACKGROUND: Low-dose computed tomography (LDCT) are performed routinely for lung cancer screening. However, a large amount of nonpulmonary data from these scans remains unassessed. We aimed to validate a deep learning model to automatically segment and measure left atrial (LA) volumes from routine NCCT and evaluate prediction of cardiovascular outcomes. METHODS: We retrospectively evaluated 273 patients (median age 69 years, 55.5% male) who underwent LDCT for lung cancer screening. LA volumes were quantified by three expert cardiothoracic radiologists and a prototype AI algorithm. LA volumes were then indexed to the body surface area (BSA). Expert and AI LA volume index (LAVi) were compared and used to predict cardiovascular outcomes within five years. Logistic regression with appropriate univariate statistics were used for modelling outcomes. RESULTS: There was excellent correlation between AI and expert results with an LAV intraclass correlation of 0.950 (0.936-0.960). Bland-Altman plot demonstrated the AI underestimated LAVi by a mean 5.86 â€‹mL/m2. AI-LAVi was associated with new-onset atrial fibrillation (AUC 0.86; OR 1.12, 95% CI 1.08-1.18, p â€‹< â€‹0.001), HF hospitalization (AUC 0.90; OR 1.07, 95% CI 1.04-1.13, p â€‹< â€‹0.001), and MACCE (AUC 0.68; OR 1.04, 95% CI 1.01-1.07, p â€‹= â€‹0.01). CONCLUSION: This novel deep learning algorithm for automated measurement of LA volume on lung cancer screening scans had excellent agreement with manual quantification. AI-LAVi is significantly associated with increased risk of new-onset atrial fibrillation, HF hospitalization, and major adverse cardiac and cerebrovascular events within 5 years.

Implementation of a Procainamide-Based Cardioversion Strategy for the Management of Recent-Onset Atrial Fibrillation.

Atrial fibrillation/flutter (AF) remains the most common rhythm disturbance in adult patients presenting to emergency departments (EDs). Although pharmacologic cardioversion has been established as safe and effective in recent-onset AF, its use in U.S. EDs is uncommon. The purpose of this study was to assess the safety and efficacy of intravenous (IV) procainamide for pharmacologic cardioversion in patients presenting to the ED with AF of <48-hr duration. Patients presenting to the ED with recent-onset AF (<48 hr) undergoing a cardioversion strategy with IV procainamide from 2017 to 2019 were reviewed. Clinical outcomes assessed included rates of cardioversion, hospital admission, stroke, and return ED visits for arrhythmia or serious adverse events. A total of 64 patients received procainamide therapy-60.9% achieved cardioversion and 35.9% were admitted to the hospital. The mean dose was 1062.4 mg (12.1 mg/kg). No patients returned to the ED secondary to stroke and 9.4% experienced complications attributed to procainamide, the most common being hypotension. Within 30 days of therapy, 20.3% of patients returned to the ED secondary to arrhythmia recurrence. Patients experiencing cardioversion with procainamide were less likely to be admitted to the hospital (25.6% vs. 52.0%; p = 0.04) or receive a rate control agent (17.9% vs. 64.0%; p = 0.001). There was no significant difference in the rate of 30-day return between those who experienced pharmacologic cardioversion and those who did not (p = 0.220). The implementation of a procainamide-based acute cardioversion strategy for patients presenting to the ED with recent-onset AF resulted in a 60% cardioversion rate, which was associated with a significantly higher rate of discharge from the ED. Transient hypotension was the most common adverse event. Further investigation into ED-based protocols for management of recent-onset AF is necessary to better understand their safety and efficacy.

Evaluating outcomes of same-day discharge after catheter ablation for atrial fibrillation in a real-world cohort.

BACKGROUND: As same-day discharge (SDD) after catheter ablation (CA) for atrial fibrillation (AF) is increasingly utilized, it is important to further investigate this approach. OBJECTIVE: To investigate the safety and efficacy of SDD after CA for AF in a large nationwide administrative sample. METHODS: The IBM MarketScan Commercial Claims and Encounters database was used to identify adult patients under 65 years undergoing CA for AF (2016-2020). Eligible patients were indexed to date of first CA and classified into SDD or overnight stay (ONS) groups based on length of service. A 1:3 propensity score matching was used to create comparable SDD:ONS samples. Study outcomes were CA-related complications within 30 days after index procedure and AF recurrence within 1 year. Cox proportional hazards models were estimated for outcome comparison. RESULTS: In the postmatch 30-day cohort, there were 1610 SDD and 4637 ONS patients with mean age 56.1 (± 7.6) years. There was no significant difference in composite 30-day postprocedural complication rate between SDD and ONS groups (2.7% vs 2.8%, respectively; P = .884). The most common complications were cerebrovascular events (0.7% vs 0.7%; P = .948), vascular access events (0.6% vs 0.6%; P = .935), and pericardial complications (0.6% vs 0.5%; P = .921). Further, no significant difference in composite AF recurrence rate at 1 year was observed among SDD and ONS groups (10.2% vs 8.8%; hazard ratio = 1.167; 95% confidence interval 0.935-1.455; P = .172). CONCLUSION: In a large, propensity-matched, real-world sample, SDD appears to be safe and have similar outcomes compared with overnight observation following CA for AF.

Electrical delays in quadripolar leads with cardiac resynchronization therapy.

BACKGROUND: Pacing at sites of late intraventricular activation (QLV) or long interventricular conduction (right ventricle [RV]-left ventricular [LV]) have been associated with improved cardiac resynchronization therapy (CRT) outcomes. Quadripolar leads improve CRT outcomes by allowing for electrical repositioning to optimize pacing sites. However, little is known regarding the effect of such repositioning on electrical delay. OBJECTIVE: Determine the relationship between different electrical bipoles from a quadripolar lead and measures of electrical delay. METHODS: Forty-six patients underwent CRT with a quadripolar lead. The RV-LV and QLV intervals were measured for both the proximal and distal bipoles and the difference (Δ) between bipoles for each measure were calculated. Multivariate analyses were performed to identify predictors of electrical delays. RESULTS: This was a typical CRT population with a mean age of 65 years and ejection fraction of 27%, with left bundle branch block (LBBB) present in 70%. The regression model for ΔQLV was significant (p = .05), with both gender (p = .008) and LBBB status (p = .020) significant predictors. The overall regression model for ΔRV-LV was not significant. ΔQLV and ΔRV-LV were significant among LBBB patients. Among non-LBBB, only ΔRV-LV was significant (mean: 7.2 ms, p = .006). ΔRV-LV versus ΔQLV were strongly correlated in LBBB (R2 = .92) but not non-LBBB (R2 = .06). CONCLUSION: In LBBB, ΔRV-LV and ΔQLV are closely correlated suggesting that the proximal bipole and thus basal LV pacing sites should be selected when feasible. Greater variation in activation pattern is present in non-LBBB, so pacing sites should be individualized.

Patient characteristics, care patterns, and outcomes of atrial fibrillation associated hospitalizations in patients with chronic kidney disease and end-stage renal disease.

BACKGROUND: Chronic Kidney Disease (CKD) and end-stage renal disease (ESRD) are associated with poor outcomes in patients with cardiovascular disease. There is a paucity of contemporary data on in-hospital outcomes and care patterns of atrial fibrillation (AF) associated hospitalizations CKD and ESRD. METHODS: Outcomes and care patterns were evaluated in GWTG-AFIB database (Jan 2013-Dec 2018), including in-hospital mortality, use of a rhythm control strategy, and oral anticoagulation (OAC) prescription at discharge among eligible patients. Generalized logistic regression models with generalized estimating equations were used to ascertain differences in outcomes. Hospital-level variation in OAC prescription and rhythm control was also evaluated. RESULTS: Among 50,154 patients from 105 hospitals the median age was 70 years (interquartile range 61-79) and 47.3% were women. The prevalence of CKD was 36.0% while that of ESRD was 1.6%. Among eligible patients, discharge OAC prescription rates were 93.6% for CKD and 89.1% for ESRD. After adjustment, CKD and ESRD were associated with higher in-hospital mortality (odds ratio [OR] 3.08, 95% confidence interval [CI] 1.57-6.03 for ESRD and OR 2.02, 95% CI 1.52-2.67 for CKD), lower odds of OAC prescription at discharge (OR 0.59, 95% CI 0.44-0.79 for ESRD and OR 0.84, 95% CI 0.75-0.94 for CKD) compared with normal renal function. CKD was associated with lower utilization of rhythm control strategy (OR 0.92, 95% CI 0.87-0.98) with no significant difference between ESRD and normal renal function (OR 1.32, 95% CI 0.79-1.11). There was large hospital-level variation in OAC prescription at discharge (MOR 2.34, 95% CI 2.05-2.76) and utilization of a rhythm control strategy (MOR 2.69, 95% CI 2.34-3.21). CONCLUSIONS: CKD/ESRD is associated with higher in-hospital mortality, less frequent rhythm control, and less OAC prescription among patients hospitalized for AF. There is wide hospital-level variation in utilization of a rhythm control strategy and OAC prescription at discharge highlighting potential opportunities to improve care and outcomes for these patients, and better define standards of care in this patient population.

Same-day discharge after catheter ablation in patients with atrial fibrillation in a large nationwide administrative claims database.

BACKGROUND: Catheter ablation (CA) is a common treatment for atrial fibrillation (AF). This study evaluated outcomes of same day discharge (SDD) versus overnight stay (ONS) among AF patients undergoing outpatient CA. METHODS: The Optum SES Clinformatics Extended Data Mart database was used to identify patients ≥18 years of age undergoing outpatient CA for AF (2016-2020). Eligible patients were indexed to the date of first CA and classified into SDD and ONS groups based on the length of service. A 1:3 propensity score matching was used to create comparable SDD:ONS samples. The primary safety outcome was CA-related complications within 30 days of index procedure. The primary efficacy outcome was AF recurrence within 1 year. Cox proportional hazards models were estimated for outcome comparison. RESULTS: In the postmatch 30-day cohort for safety evaluation, there were 6600 patients (1660 [25.2%] SDD; 4940 [74.8%] ONS), with a mean age of 66.6 years. There was no significant difference in the 30-day composite rate of postablation complications (4.7% [78/1660] vs. 3.8% [187/4940]; p = 0.100) and 1-year composite rate of AF recurrence (14.3% [142/996] vs. 14.5% [430/2972]; p = 0.705) between the SDD and ONS groups. CONCLUSION: This study demonstrated that SDD following CA to treat patients with AF is safe, with low rates of postablation complications and AF recurrence, which were comparable to rates in patients with an ONS after CA.

Catheter ablation and healthcare utilization and cost among patients with paroxysmal versus persistent atrial fibrillation.

BACKGROUND: Ablation reduces atrial fibrillation (AF) burden and improves health-related quality of life. The relationship between ablation, healthcare utilization, and AF type (paroxysmal AF [PAF] vs persistent AF [PsAF]) remains unclear. OBJECTIVE: To compare changes in AF-related healthcare utilization and costs from preablation to postablation among patients with PAF and PsAF. METHODS: Patients (2794 PAF, 1909 PsAF) undergoing ablation (2016-2018) were identified using the Optum database. Outcomes included inpatient admissions, emergency department (ED) visits, office visits, cardioversion, and antiarrhythmic drug (AAD) use. Costs (2018 US$) and outcomes were compared for the year before/after ablation using the McNemar test and Wilcoxon signed rank test. RESULTS: Compared to PAF patients, PsAF patients were older (68.6 ± 9.0 years vs 67.4 ± 9.9 years, P < .0001), were less commonly female (36.3% vs 44.1%, P < .0001), and more commonly had a CHA2DS2-VASc ≥ 3(71.2% vs 62.7%, P < .0001). The 12-month postablation costs were lower for AF-specific inpatient admissions (PAF -28%, PsAF -33%), ED visits (PAF -76%, PsAF -70%), AAD prescription fills (PAF -25%, PsAF -7%), and cardioversions (PAF -59%, PsAF -55%) as compared to 12 months before ablation. Although these reductions were observed for both PAF and PsAF patients, absolute costs remained higher for PsAF. Total AF costs were higher during the 1 year after ablation vs before ablation (PAF: 11%, P < .0001; PsAF: 10%, P < .0001) owing to repeat ablation. However, in the 18-month follow-up analysis, postablation costs were overall reduced (PAF: 35%, P < .0001; PsAF: 34%, P < .0001), despite including costs from repeat ablation. CONCLUSION: Significant reductions in healthcare utilization and costs were observed among PAF and PsAF patients undergoing ablation. These data suggest a strategy of earlier ablation may reduce long-term healthcare utilization and costs.

Impact of age on catheter ablation of premature ventricular contractions.

INTRODUCTION: Catheter ablation (CA) of frequent premature ventricular contractions (PVC) is increasingly performed in older patients as the population ages. The aim of this study was to assess the impact of age on procedural characteristics, safety and efficacy on PVC ablations. METHODS: Consecutive patients with symptomatic PVCs undergoing CA between 2015 and 2020 were evaluated. Acute ablation success was defined as the elimination of PVCs at the end of the procedure. Sustained success was defined as an elimination of symptoms, and ≥80% reduction of PVC burden determined by Holter-electrocardiogram during long-term follow. Patients were sub-grouped based on age (<65 vs. ≥65 years). RESULTS: A total of 114 patients were enrolled (median age 64 years, 71% males) and followed up for a median duration of 228 days. Baseline and procedural data were similar in both age groups. A left-sided origin of PVCs was more frequently observed in the elderly patient group compared to younger patients (83% vs. 67%; p = .04). The median procedure time was significantly shorter in elderly patients (160 vs. 193 min; p = .02). The rates of both acute (86% vs. 92%; p = .32) and sustained success (70% vs. 71%; p = .90) were similar between groups. Complications rates (3.7%) did not differ between the two groups. CONCLUSION: In a large series of patients with a variety of underlying arrhythmia substrates, similar rates of acute procedural success, complications, and ventricular arrhythmia-free-survival were observed after CA of PVCs. Older age alone should not be a reason to withhold CA of PVCs.

Guideline-Concordant Antiarrhythmic Drug Use in the Get With The Guidelines-Atrial Fibrillation Registry.

BACKGROUND: Antiarrhythmic drug (AAD) therapy for atrial fibrillation (AF) can be associated with both proarrhythmic and noncardiovascular toxicities. Practice guidelines recommend tailored AAD therapy for AF based on patient-specific characteristics, such as coronary artery disease and heart failure, to minimize adverse events. However, current prescription patterns for specific AADs and the degree to which these guidelines are followed in practice are unknown. METHODS: Patients enrolled in the Get With The Guidelines-Atrial Fibrillation registry with a primary diagnosis of AF discharged on an AAD between January 2014 and November 2018 were included. We analyzed rates of prescription of each AAD in several subgroups including those without structural heart disease. We classified AAD use as guideline concordant or nonguideline concordant based on 6 criteria derived from the American Heart Association/American College of Cardiology/Heart Rhythm Society AF guidelines. Guideline concordance for amiodarone was not considered applicable, since its use is not specifically contraindicated in the guidelines for reasons such as structural heart disease or renal function. We analyzed guideline-concordant AAD use by specific patient and hospital characteristics, and regional and temporal trends. RESULTS: Among 21 921 patients from 123 sites, the median age was 69 years, 46% female and 51% had paroxysmal AF. The most commonly prescribed AAD was amiodarone (38%). Sotalol (23.2%) and dofetilide (19.2%) were each more commonly prescribed than either flecainide (9.8%) or propafenone (4.8%). Overall guideline-concordant AAD prescription at discharge was 84%. Guideline-concordant AAD use by drug was as follows: dofetilide 93%, sotalol 66%, flecainide 68%, propafenone 48%, and dronedarone 80%. There was variability in rate of guideline-concordant AAD use by hospital and geographic region. CONCLUSIONS: Amiodarone remains the most commonly prescribed AAD for AF followed by sotalol and dofetilide. Rates of guideline-concordant AAD use were high, and there was significant variability by specific drugs, hospitals, and regions, highlighting opportunities for additional quality improvement.

Healthcare utilization and cost in patients with atrial fibrillation and heart failure undergoing catheter ablation.

BACKGROUND: Catheter ablation is an effective treatment for patients with atrial fibrillation (AF) and heart failure (HF). However, little is known about how healthcare utilization and cost change after ablation in this population. We sought to determine healthcare utilization and cost patterns among patients with AF and HF undergoing ablation. METHODS: Using a large United States administrative database, we identified (n = 1568) treated with ablation with a primary and secondary diagnosis of AF and HF, respectively, were evaluated 1-year pre- and postablation for outcomes including inpatient admissions (AF or HF), emergency department (ED) visits, cardioversions, length of stay (LOS), and cost. A secondary analysis was extended to 3-years postablation. RESULTS: Reductions were observed in AF-related admissions (64%), LOS (65%), cardioversions (52%), ED visits (51%, all values, p < .0001), and HF-related admissions (22%, p = .01). There was a 40% reduction in inpatient admission cost ($4165 preablation to $2510 postablation, p < .0001). In a sensitivity analysis excluding repeat-ablation patients, a greater reduction in overall AF management cost was observed compared to the full cohort (-43% vs. -2%). Comparing 1-year pre- to 3-years postablation, both total mean AF-management cost ($850 per-patient per-month 1-year pre- to $546 3-years postablation, p < .0001) and AF-related healthcare utilization was reduced. CONCLUSIONS: Catheter ablation in patients with AF and HF resulted in significant reductions in healthcare utilization and cost through 3-years of follow-up. This reduction was observed regardless of whether repeat ablation was performed, reflecting the positive impact of ablation on longer term cost reduction.

Intracardiac echocardiography use and outcomes after catheter ablation of ventricular tachycardia.

Aim: To compare outcomes among patients with implantable cardioverter defibrillator/cardiac resynchronization therapy-defibrillator undergoing outpatient ventricular tachycardia (VT) catheter ablation using intracardiac echocardiography (ICE) versus no ICE. Patients & methods: Patients were classified into ICE (n = 1143)/non-ICE (n = 1677) groups based on ICE procedure codes. Patients in each group were propensity matched on study covariates. Survival analyses were used to assess outcomes. To examine residual confounding, falsification outcomes were evaluated. Results: ICE patients had a 24% lower risk of all-cause readmissions, 24% lower risk of cardiovascular-related and 20% lower risk of VT-related readmissions compared with non-ICE patients. Falsification analyses for ICE use association were nonsignificant. Conclusion: Patients with implantable cardioverter defibrillator/cardiac resynchronization therapy-defibrillator undergoing VT ablation with ICE use had significantly lower likelihood of VT-related readmission.

Electromagnetic interference from left ventricular assist devices in patients with subcutaneous implantable cardioverter-defibrillators.

INTRODUCTION: Interactions of left ventricular assist devices (LVADs) with transvenous implantable cardioverter-defibrillator systems (ICDs) have been widely reported. However, less is known regarding the impact of electromagnetic interference (EMI) from LVADs on subcutaneous ICD function. METHODS AND RESULTS: A comprehensive literature search was performed on PubMed, Cochrane central registry, and Google Scholar using the search terms "subcutaneous implantable cardioverter-defibrillator and left ventricular assist devices," "electromagnetic interference, LVAD, and subcutaneous ICD," "EMI and S-ICD," and "inappropriate shocks, LVAD, and ICD." Demographic and programming data were extracted from the reports and authors as needed. A total of seven cases of EMI in LVAD patients with subcutaneous ICD (S-ICD) devices were found. In addition three previously unreported cases from our center were included. All cases involved either a heartware ventricular assist device or HeartMate III LVAD with a pre-existing S-ICD. In all patients, both the primary and secondary vectors had inappropriate sensing due to EMI. Three patients were reprogramed to the alternate vector with appropriate sensing. The S-ICD was either inactivated or replaced with a transvenous device in six patients. A single patient was left sensing in the alternate vector. There were no reports of inability to interrogate S-ICD systems in patients with LVADs. CONCLUSION: The risk of inappropriate shocks from LVADs should be considered in pre-existing patients with S-ICD, particularly when the heartware ventricular assist device or HeartMate III LVAD device is present. Reprogramming of the sensing vector can occasionally avoid this issue but often the S-ICD needs to be inactivated.

Persistent Asthma Is Associated With Increased Risk for Incident Atrial Fibrillation in the MESA.

BACKGROUND: Asthma and atrial fibrillation (AF) share an underlying inflammatory pathophysiology. We hypothesized that persistent asthmatics are at higher risk for developing AF and that this association would be attenuated by adjustment for baseline markers of systemic inflammation. METHODS: The MESA (Multi-Ethnic Study of Atherosclerosis) is a prospective longitudinal study of adults free of cardiovascular disease at baseline. Presence of asthma was determined at exam 1. Persistent asthma was defined as asthma requiring use of controller medications. Intermittent asthma was defined as asthma without use of controller medications. Participants were followed for a median of 12.9 (interquartile range, 10-13.6) years for incident AF. Multivariable Cox regression models were used to assess associations of asthma subtype and AF. RESULTS: The 6615 participants were a mean (SD) 62.0 (10.2) years old (47% male, 27% black, 12% Chinese, and 22% Hispanic). AF incidence rates were 0.11 (95% CI, 0.01-0.12) events/10 person-years for nonasthmatics, 0.11 (95% CI, 0.08-0.14) events/10 person-years for intermittent asthmatics, and 0.19 (95% CI, 0.120.49) events/10 person-years for persistent asthmatics (log-rank P=0.008). In risk-factor adjusted models, persistent asthmatics had a greater risk of incident AF (hazard ratio, 1.49 [95% CI, 1.03-2.14], P=0.03). IL (Interleukin)-6 (hazard ratio, 1.26 [95% CI, 1.13-1.42]), TNF (tumor necrosis factor)-α receptor 1 (hazard ratio, 1.09 [95% CI, 1.08-1.11]) and D-dimer (hazard ratio, 1.10 [95% CI, 1.02-1.20]) predicted incident AF, but the relationship between asthma and incident AF was not attenuated by adjustment for any inflammation marker (IL-6, CRP [C-reactive protein], TNF-α R1, D-dimer, and fibrinogen). CONCLUSIONS: In a large multiethnic cohort with nearly 13 years follow-up, persistent asthma was associated with increased risk for incident AF. This association was not attenuated by adjustment for baseline inflammatory biomarkers.