Comprehensive Atrial Fibrillation Burden and Symptom Reduction Post-Ablation: Insights from DECAAF II.

INTRODUCTION: Traditional AF recurrence after catheter ablation is reported as a binary outcome. However, a paradigm shift towards a more granular definition, considering arrhythmic or symptomatic burden, is emerging. HYPOTHESIS: We hypothesize that ablation reduces AF burden independently of conventional recurrence status in persistent AF patients, correlating with symptom burden reduction. METHODS: 98 patients with persistent AF from the DECAAFII trial with pre-ablation follow-up were included. Patients recorded daily single-lead ECG strips, defining AF burden as the proportion of AF days among total submitted ECG days. The primary outcome was atrial arrhythmia recurrence. The Atrial Fibrillation Severity Scale (AFSS) was administered pre-ablation and at 12-months post-ablation. RESULTS: At follow-up, 69 patients had atrial arrhythmia recurrence and 29 remained in sinus rhythm. These patients were categorized into a recurrence (n=69) and no-recurrence group (n=29). Both groups had similar baseline characteristics, but recurrence patients were older (p=0.005), had a higher prevalence of hyperlipidemia (p=0.007), and a larger LA volume (p=0.01). There was a reduction in AF burden in the recurrence group when compared to their pre-ablation burden (65% vs. 15%, p<0.0001). Utah Stage 4 fibrosis and diabetes predicted less improvement in AF burden. The symptom severity score at 12 months post-ablation was significantly reduced compared to the pre-ablation score in the recurrence group, and there was a significant correlation between the reduction in symptom severity score and AF burden reduction (R=0.39, p=0.001). CONCLUSION: Catheter ablation reduces AF burden irrespective of arrhythmia recurrence post-procedure. There's a strong correlation between AF burden reduction and symptom improvement post-ablation. Notably, elevated left atrial fibrosis impedes AF burden decrease following catheter ablation.

Left atrial volume affects the correlation of voltage map with magnetic resonance imaging.

BACKGROUND: The low-voltage area detected by electroanatomic mapping (EAM) is a surrogate marker of left atrial fibrosis. However, the correlation between the EAM and late gadolinium enhancement magnetic resonance imaging (LGE-MRI) has been inconsistent among studies. This study aimed to investigate how LA size affects the correlation between EAM and LGE-MRI. METHODS: High-density EAMs of the LA during sinus rhythm were collected in 22 patients undergoing AF ablation. The EAMs were co-registered with pre-ablation LGE-MRI models. Voltages in the areas with and without LGE were recorded. Left atrial volume index (LAVI) was calculated from MRI, and LAVI > 62 ml/m2 was defined as significant LA enlargement (LAE). RESULTS: Atrial bipolar voltage negatively correlates with the left atrial volume index. The median voltages in areas without LGE were 1.1 mV vs 2.0 mV in patients with vs without significant LAE (p = 0.002). In areas of LGE, median voltages were 0.4 mV vs 0.8 mV in patients with vs without significant LAE (p = 0.02). A voltage threshold of 1.7 mV predicted atrial LGE in patients with normal or mildly enlarged LA (sensitivity and specificity of 74% and 59%, respectively). In contrast, areas of voltage less than 0.75 mV correlated with LGE in patients with significant LA enlargement (sensitivity 68% and specificity 66%). CONCLUSIONS: LAVI affects left atrial bipolar voltage, and the correlation between low-voltage areas and LGE-MRI. Distinct voltage thresholds according to the LAVI value might be considered to identify atrial scar by EAM.

Smartphone AF Burden During the Blanking Period Predicts Catheter Ablation Outcomes: Insights From DECAAF II.

BACKGROUND: Atrial fibrillation (AF) recurrence during the blanking period is under investigated. With the rise of smartphone-based electrocardiogram (ECG) monitoring, there's potential for better prediction and understanding of AF recurrence trends. OBJECTIVES: In this study the authors hypothesize that AF burden derived from a single-lead Smartphone ECG during the blanking period predicts recurrence of atrial arrhythmias after ablation. METHODS: 630 patients with persistent AF undergoing ablation were included from the DECAAF II (Effect of MRI-Guided Fibrosis Ablation vs Conventional Catheter Ablation on Atrial Arrhythmia Recurrence in Patients With Persistent Atrial Fibrillation) trial. Patients recorded daily ECG strips using a smartphone device. AF burden was defined as the ratio of ECG strips with AF to the total number of strips submitted. The primary outcome was the recurrence of atrial arrhythmia. RESULTS: Recurrence occurred in 301 patients during the 18-month follow-up period. In patients who developed recurrent arrhythmia after 90 days of follow-up, AF burden during the blanking period was significantly higher when compared with patients who remained in sinus rhythm (31.3% vs 7.5%; P < 0.001). AF burden during the blanking period was an independent predictor of arrhythmia recurrence (HR: 1.41; 95% CI: 1.36-1.47; P < 0.001). Through grid searching, an AF burden of 18% best discriminates between recurrence and no-recurrence groups, yielding a C-index of 0.748. After a follow-up period of 18 months, recurrence occurred in 33.7% of patients (147 of 436) with an AF burden <18% and in 79.4% of patients (154 of 194) with an AF burden >18% (HR: 4.57; 95% CI: 3.63-5.75; P < 0.001). CONCLUSIONS: A high AF burden derived from a smartphone ECG during the blanking period is a strong predictor of atrial arrhythmia recurrences after ablation.

Baseline natriuretic peptides as a predictor of atrial fibrillation recurrence after radiofrequency-based pulmonary vein isolation in a non-heart failure population: A subanalysis from DECAAF II.

BACKGROUND: Brain natriuretic peptide (BNP) is a marker of myocardial stretch and may have prognostic significance in patients with atrial fibrillation (AF) without heart failure (HF). We investigated the association between baseline BNP levels and arrhythmia recurrence following pulmonary vein isolation (PVI) among patients with persistent AF without HF. METHODS: We analyzed 125 patients with persistent AF without HF who had baseline BNP measured from the DECAAF II trial. The primary outcome was arrhythmia recurrence following ablation. The baseline characteristics across the two groups were compared using Chi-square test and Wilcoxon rank test accordingly. Cox regression analysis was used to analyze the association between baseline BNP levels and the primary outcome. RESULTS: Across the entire cohort, 64 (51%) patients experienced arrhythmia recurrence. When comparing patients who experienced arrythmia recurrence to patients who did not, patients with recurrent arrhythmia had higher levels of pre-ablation BNP, as evidenced by differences in means (330.05 pg/mL) compared to patients without recurrent arrhythmia (182.39 pg/mL) (p < .05). A cut-off BNP value of 300 pg/mL provided the largest area under curve (AUC) of receiver-operating characteristic (ROC) curve on univariate logistic regression. On unadjusted Cox analysis, for every 100 unit increase in BNP, the hazard ratio for the primary outcome increased 1.09 (1.026-1.158) times (p = .004). After adjusting for sex, hypertension, and stroke, the results remained significant (HR = 1.8516, CI 95% [1.0139 - 3.381], p = .045). CONCLUSION: In the non-heart failure population, BNP levels predict AF recurrence following PVI in persistent AF patients.

Catheter ablation improved ejection fraction in persistent AF patients: a DECAAF-II sub analysis.

AIMS: The aim of our study was to assess differences in post-ablation atrial fibrillation (AF) recurrence and burden and to quantify the change in LVEF across different congestive heart failure (CHF) subcategories of the DECAAF-II population. METHODS AND RESULTS: Differences in the primary outcome of AF recurrence between CHF and non-CHF groups was calculated. The same analysis was performed for the three subgroups of CHF and the non-CHF group. Differences in AF burden after the 3-month blanking period between CHF and non-CHF groups was calculated. Improvement in LVEF was calculated and compared across the three CHF groups. Improvement was also calculated across different fibrosis stages. There was no significant differences in AF recurrence and AF burden after catheter ablation between CHF and non-CHF patients and between different CHF subcategories. Patients with heart failure with reduced ejection fraction (HFrEF) experienced the greatest improvement in EF following catheter ablation (CA, 16.66% ± 11.98, P < 0.001) compared to heart failure with moderately reduced LVEF, and heart failure with preserved EF (10.74% ± 8.34 and 2.00 ± 8.34 respectively, P-value < 0.001). Moreover, improvement in LVEF was independent of the four stages of atrial fibrosis (7.71 vs. 9.53 vs. 5.72 vs. 15.88, from Stage I to Stage IV respectively, P = 0.115). CONCLUSION: Atrial fibrillation burden and recurrence after CA is similar between non-CHF and CHF patients, independent of the type of CHF. Of all CHF groups, those with HFrEF had the largest improvement in LVEF after CA. Moreover, the improvement in ventricular function seems to be independent of atrial fibrosis in patients with persistent AF.

Predictors of Lesions Contiguity and Transmurality in Canine Ventricular Models After Catheter Ablation.

Background: Interlesion gaps and transmurality of lesions after catheter ablation can precipitate suboptimal efficacy in preventing arrhythmias. Aims: We aim to assess predictors of acute transmural lesion formation and the interlesion distance threshold for creating a continuous, chronic scar after ventricular ablation. Materials and Methods: Ablation procedures were performed on 7 canines followed by late gadolinium enhancement MRI (LGE-MRI). Transmurality of lesions was assessed by 2 independent operators. Ablation parameters such as duration (s), power (W), temperature (C), contact force (CF) (g), were collected for each ablation point. After 7-12 weeks, LGE-MRI was performed, followed by euthanasia, and heart excision. Some lesions were created in pair. Lesion pairs were spaced 7-21 mm apart as measured by Electroanatomic mapping (EAM), with different operating parameters (power 35 or 50W, duration of energy delivery 10, 20 or 30s and contact force of 10g or above). We performed a logistic regression analysis to determine predictors of transmural lesion formation. Results: Eighty-one radiofrequency ablation were performed in total [33 in the Left ventricle (LV) and 48 in the Right ventricle (RV)]. Higher CF was a significant predictor of transmural lesion formation (ß = 0.15, OR = 1.16, 95% CI [1.03 - 1.3], p = 0.01), and lesions delivered in the RV were more frequently transmural than lesions delivered in the LV (ß = -2.43, OR = 0.09, 95%CI [0.02 - 0.34], p < 0.001). For the paired analysis, thirty-eight lesions were created contiguously: fourteen connected lesions and twenty-four unconnected lesions. EAM distance was significantly larger in unconnected lesions than connected lesions (16.17 ± 0.92 mm vs. 11.51 ± 0.68 mm, respectively, p < 0.05). We concluded that an interlesion distance of less than 10 mm is required to prevent gap formation. Average volumes in unconnected lesions (n = 24) at the acute and chronic stages were 0.55 ± 0.11 cm3 and 0.20 ± 0.02 cm3, respectively. On average, lesion volumes were 64% (p < 0.05) smaller at the chronic stage compared to the acute stage. Among connected lesions (n = 14), we observed a volume of 1.19 ± 0.8 cm3 and 0.39 ± 0.15 cm3 at the acute and chronic stages, respectively. These connected lesions reduced in volume by 67% on average. Conclusion: To create contiguous scars on the ventricular endocardial surface, paired lesions should be spaced less than ten millimeters apart. Higher contact force should be used in ventricular ablation to create transmural lesions.

Atrial Fibrillation and Acute Ischemic Stroke: Evaluation of the Contemporary 2018 National Inpatient Sample Database.

Background: Atrial fibrillation (AF) in acute ischemic stroke (AIS) is considered a binary entity regardless of AF type. We aim to investigate in-hospital morbidity and mortality among patients with nonparoxysmal AF-related AIS. Methods: Patients hospitalized for AIS with associated paroxysmal or persistent AF were identified from the 2018 national inpatient sample database. We compared in-hospital mortality, stroke-related morbidity, hospital cost, length of stay, and discharge disposition in patients hospitalized with paroxysmal or persistent AF. Results: A total of 26,470 patients were hospitalized for AIS with paroxysmal or persistent AF. Patient with AIS with persistent AF had a longer hospital length of stay (paroxysmal AF, mean [M] 5.7 days, standard deviation [SD] ±6.8 days; persistent AF, M 7.4 days, SD ±11.9 days, P < 0.001) and in-hospital costs (paroxysmal AF, M $15,449, SD ±$18,320; persistent AF, M $19,834 SD ±$23,312, P < 0.001). Patients with AIS with permanent AF had higher in-hospital mortality (paroxysmal AF, 4.6%, vs permanent AF, 6.2%, P < 0.001). Indirect markers of stroke-related disability, like intracranial hemorrhage (odds ratio [OR]: 1.9, 95% confidence interval (CI): 1.6-2.2), need for gastrostomy (OR: 2.1, 95% CI: 1.8-2.4), and tracheostomy (OR: 3.1, 95% CI: 2.1-4.4) were more associated with AIS from persistent AF. Conclusions: Persistent AF is associated with poor in-hospital stroke-related outcome, possibly due to a worse thrombo-embolic phenomenon. AF pattern may be a harbinger of worse stroke-related morbidity.

Contexte: La fibrillation auriculaire (FA) dans l'accident vasculaire cérébral (AVC) ischémique aigu est considérée comme une entité binaire, quel que soit le type de FA. Nous voulons étudier la morbidité et la mortalité chez les patients hospitalisés pour un AVC ischémique aigu lié à une FA non paroxystique. Méthodologie: Des patients hospitalisés pour un AVC ischémique aigu accompagné d'une FA paroxystique ou persistante ont été répertoriés à partir d'une base de données d'échantillons de patients hospitalisés à l'échelle du pays en 2018. Nous avons comparé la mortalité à l'hôpital, la morbidité liée à l'AVC, le coût de l'hospitalisation, la durée du séjour et les dispositions du congé chez les patients hospitalisés pour une FA paroxystique ou persistante. Résultats: Au total, 26 470 patients ont été hospitalisés pour un AVC ischémique aigu accompagné d'une FA paroxystique ou persistante. Le séjour à l'hôpital était plus long pour les patients atteints d'un AVC ischémique aigu accompagné d'une FA persistante (FA paroxystique, moyenne [M] de 5,7 jours, écart-type [ET] ±6,8 jours; FA persistante, M de 7,4 jours, ET ±11,9 jours, p < 0,001) et les coûts d'hospitalisation ont été plus élevés dans ce groupe de patients (FA paroxystique, M de 15 449 $, ET ±18 320 $; FA persistante, M de 19 834 $, ET ±23 312 $, p < 0,001). La mortalité à l'hôpital était plus élevée chez les patients atteints d'un AVC ischémique aigu accompagné d'une FA permanente (FA paroxystique, 4,6 % vs FA permanente, 6,2 %, p < 0,001). Des marqueurs indirects d'incapacité liée à l'AVC, comme une hémorragie intracrânienne (rapport des cotes [RC] : 1,9, intervalle de confiance [IC] à 95 % : 1,6-2,2), la nécessité d'une gastrostomie (RC : 2,1, IC à 95 % : 1,8-2,4) ou d'une trachéostomie (RC : 3,1, IC à 95 % : 2,1-4,4) ont été davantage associés à l'AVC ischémique aigu découlant d'une FA persistante. Conclusions: La FA persistante est associée à une issue défavorable liée à l'AVC chez les patients hospitalisés, possiblement en raison d'un phénomène thrombo-embolique aggravé. La forme de la FA peut être annonciatrice d'une plus grande morbidité liée à l'AVC.

Studying the Effect of Long COVID-19 Infection on Sleep Quality Using Wearable Health Devices: Observational Study.

BACKGROUND: Patients with COVID-19 have increased sleep disturbances and decreased sleep quality during and after the infection. The current published literature focuses mainly on qualitative analyses based on surveys and subjective measurements rather than quantitative data. OBJECTIVE: In this paper, we assessed the long-term effects of COVID-19 through sleep patterns from continuous signals collected via wearable wristbands. METHODS: Patients with a history of COVID-19 were compared to a control arm of individuals who never had COVID-19. Baseline demographics were collected for each subject. Linear correlations among the mean duration of each sleep phase and the mean daily biometrics were performed. The average duration for each subject's total sleep time and sleep phases per night was calculated and compared between the 2 groups. RESULTS: This study includes 122 patients with COVID-19 and 588 controls (N=710). Total sleep time was positively correlated with respiratory rate (RR) and oxygen saturation (SpO2). Increased awake sleep phase was correlated with increased heart rate, decreased RR, heart rate variability (HRV), and SpO2. Increased light sleep time was correlated with increased RR and SpO2 in the group with COVID-19. Deep sleep duration was correlated with decreased heart rate as well as increased RR and SpO2. When comparing different sleep phases, patients with long COVID-19 had decreased light sleep (244, SD 67 vs 258, SD 67; P=.003) and decreased deep sleep time (123, SD 66 vs 128, SD 58; P=.02). CONCLUSIONS: Regardless of the demographic background and symptom levels, patients with a history of COVID-19 infection demonstrated altered sleep architecture when compared to matched controls. The sleep of patients with COVID-19 was characterized by decreased total sleep and deep sleep.

Esophageal temperature during atrial fibrillation ablation poorly predicts esophageal injury: An observational study.

BACKGROUND: Esophageal injury (EI) remains a concern when performing pulmonary vein isolation (PVI) using the high-power short-duration (HPSD) technique. OBJECTIVE: We aim to indicate that high esophageal temperature during HPSD PVI does not correlate with positive esophageal endoscopy (EGD) findings. METHODS: A retrospective observational study was performed on 43 patients undergoing PVI using HPSD (50 W for 6-7 seconds per lesion) at Tulane Medical Center from July 2020 to January 2021. Esophageal temperature was monitored throughout the procedure using a temperature probe and patients underwent EGD the following day. Small ulcers, nonbleeding erosions, erythema, and/or esophagitis were considered positive EGD findings. RESULTS: Mean age was 64.9 years; 46.5% of the patients were female. Eleven patients had positive EGD findings (group 1) and 32 patients had normal EGD (group 2). There was no statistical difference in mean esophageal peak temperature between group 1 and group 2 (43.9°C ± 2.9°C and 42.5°C ± 2.3°C, respectively, P = .17). There was no association between positive EGD results and esophageal temperature during PVI. Mean baseline esophageal temperature was similar in both groups (36.1°C, P = .78). Average contact force (P = .53), ablation time (P = .67), age (P = .3096), sex (P = .4), body mass index (P = .14), and other comorbidities did not correlate with positive endoscopy results. We found positive correlation between the distance of the left atrium (LA) to esophagus and positive EGD (P = .0001). CONCLUSION: EI during HPSD PVI does not correlate to esophageal temperature changes during ablation. However, esophageal injury does correlate to a shorter proximity of the esophagus to the LA.

Acute Lesion Imaging in Predicting Chronic Tissue Injury in the Ventricles.

BACKGROUND: Chronic lesion formation after cardiac tissue ablation is an important indicator for procedural outcome. Moreover, there is a lack of knowledge regarding the features that predict chronic lesion formation. OBJECTIVE: The aim of this study is to determine whether acute lesion visualization using late gadolinium enhanced magnetic resonance imaging (LGE-MRI) can reliably predict chronic lesion size. METHODS: Focal lesions were created in left and right ventricles of canine models using either radiofrequency (RF) ablation or cryofocal ablation. Multiple ablation parameters were used. The first LGE-MRI was acquired within 1-5 h post-ablation and the second LGE-MRI was obtained 47-82 days later. Corview software was used to perform lesion segmentations and size calculations. RESULTS: Fifty-Five lesions were created in different locations in the ventricles. Chronic volume size decreased by a mean of 62.5 % (95% CI 58.83-67.97, p < 0.0005). Similar regression of lesion volume was observed regardless of ablation location (p = 0.32), ablation technique (p = 0.94), duration (p = 0.37), power (p = 0.55) and whether lesions were connected or not (p = 0.35). There was no significant difference in lesion volume reduction assessed at 47-54 days and 72-82 days after ablation (p = 0.31). Chronic lesion volume was equal to 0.32 of the acute lesion volumes (R2 = 0.75). CONCLUSION: Chronic tissue injury related to catheter ablation can be reliably modeled as a linear function of the acute lesion volume as assessed by LGE-MRI, regardless of the ablation parameters.

Effects of long-term irrigation with treated wastewater on soil quality, soil-borne pathogens, and living organisms: case study of the vicinity of El Hajeb (Tunisia).

Medium (i.e. 15 years) and long-term (i.e. 20 years) impact of irrigation using secondary-treated municipal wastewater (TWW) was assessed on two agricultural soil samples, denoted by E and G, respectively, in the vicinity of El Hajeb region (Southern Tunisia). Soil pH, electrical conductivity particle size grading, potential risk of salinity, water holding capacity and chemical composition, as well as organic matter content, pathogenic microorganisms and heavy metal concentrations in the TWW-irrigated (E and G) and rainwater-irrigated (T) soils at various depths, were monitored and compared during a 5-year experiment. Our study showed that bacterial abundance is higher in sandy-clayey soil, which has an enhanced ability to retain moisture and nutrients. The high level of bacterial flora in TWW-irrigated soils was significantly (p < 0.05) correlated (r = ~0.5) with the high level of OM. Avoidance assays have been used to assess toxic effects generated by hazards in soils. The earthworms gradually avoided the soils from the surface (20 cm) to the depth (60 cm) of the G transect and then the E transect, preferring the T transect. The same behaviour was observed for springtails, but they seem to be less sensitive to the living conditions in transects G and E than the earthworms. The avoidance response test of Eisenia andrei was statistically correlated with soil layers at the sampling sites. However, the avoidance response test of Folsomia candida was positively correlated with silt-clay content (+0.744*) and was negatively correlated with sand content (-0.744*).